State-Of-The-Art Design And Technology Can Meet Both Energy And Comfort Demands

The CFC phaseout has forced facility executives to take a hard look at their HVAC systems. At the same time, current technology offers significant opportunities for energy savings from the heating and cooling system, typically the second-largest energy user in commercial facilities. On top of all that, the definition of comfort has evolved rapidly over the past decade.

At one time, HVAC systems satisfied the comfort issue by simply making sure the work area was warm or cool enough for most occupants. Now, comfort is being refined to include indoor air quality and outside air exchange.

All in all, it's a tall order: The HVAC system is expected to achieve comfortable conditions for the individual and the masses in the office without harming the delicate global atmosphere. A good example is the CFC phaseout.

Facility executives have three choices: contain CFCs in existing chillers, convert existing units to alternative refrigerants or replace existing machines. Installing new high-efficiency equipment can result in significant energy savings.

Modern HVAC equipment offers improved efficiencies, which are being achieved with better motor performance and better temperature splits in the refrigerant tubes. Today's HVAC systems also offer better part-load efficiencies than older models. Multi-stack units and horizontal screws run more efficiently at part-load levels than earlier models. The economizer bundles are better than they used to be, so the systems run more efficiently.

The recent improvements in chiller efficiencies are the result of refinements in many small places. Manufacturers have done it by better designed compressors, by improving heat transfers. Every component has been reengineered.

New materials, notably plastics, offer major potential for increased HVAC advances that end up benefiting building owners and managers. New materials make units more efficient, easier to install and more corrosion resistant. HVAC systems are becoming more component oriented so they can be put in after the building is built.

Resolving IAQ via HVAC

One of the biggest challenges facing facility managers today is how to meet ASHRAE's current standard for outside air exchange. Variable air volume systems and normal applications need to be reexamined to meet ASHRAE fresh air standard.

To maintain energy efficiency and meet the new standard, multi-zone air-handling systems may need some overhauls. The normal unit has two decks -- one for warm air and one for cool. Provided air is mostly being recirculated, the two decks work effectively.

With the larger temperature differences involved with increased outside air, a neutral zone also may be needed. In a triple-deck system, the outside air is brought by the heat exchanger to that neutral point, before entering the air stream. The result is returned efficiency to the HVAC system in its heating and cooling modes.

Another promising solution is the use of dessicants to pre-condition air without mechanical cooling.

For buildings undergoing major retrofits, the building's air should be tested before renovations begin. Establish the levels of existing contaminants, if any, so that you have a point of reference. After renovations, the air quality should be retested. Periodically, additional IAQ tests should be conducted.

What should building owners do when indoor air actually is better than outside air, as often is the case in buildings located adjacent to major airports? Filtration for gaseous contaminants can play a major role in cleaning the building's air. The health care industry already is aware of the importance of air filtration in controlling the spread of airborne pathogens. But other building owners are just beginning to recognize the importance of proper filtration systems.

Custom comfort

Many advances have been made in HVAC control technology during the past decade. One of the most recent is the ability to control air flow, temperature and even air quality at individual workstations. Because of metabolism and dress in the office, women often complain that they are too cold, while men are too hot.

Advances in DDCs and control systems give us tools to get better air as well as energy conservation from HVAC systems. Everything now is automatic. We can set certain parameters for temperature and humidity with the outside air economizer.

And we can do so much more with the system to protect the health of the people inside the building. For example, if there is a fire and the smoke-detection system is activated, the HVAC controls can stop the air-handling system and start exhausting smoke from the space while alerting local fire and alarm departments.

Electronics in HVAC systems are becoming more integrated with each other: The air-handling unit knows how much is needed from it, and the chiller knows what each air handler is doing and can adjust itself accordingly.

Further refinements in HVAC system controls are on the near horizon. For example, comfort control that relies on more than the temperature to measure a space's overall comfort currently is being investigated by researchers, consulting engineers, ASHRAE and building controls manufacturers. Sophisticated comfort control sensors are being developed that will take into account not just the dry-bulb temperature of today's thermostats but also the mean radiant temperature, air velocity and humidity level.

Julian Arhire is a Manager with DtiCorp.com - DtiCorp.com carries more than 35,000 HVAC products, including industrial, commercial and residential parts and equipment from Honeywell, Johnson Contols, Robertshaw, Jandy, Grundfos, Armstrong and more.

How To Find Big Savings In Construction Projects

Knowing what to expect - including the places costs typically "hide" - provides an edge for efficiently managing the construction process.

Step one

A well-defined interview process will assist you in selecting the best construction manager (CM) for the job. Be thorough; replacing the CM once the job has begun is costly and raises serious questions of liability.

For renovation work, invite only CMs with considerable related experience. Interview previous clients to determine the CM's ability to handle change orders, unforeseen elements and client decisions.

Insist that the project executive, project manager and project superintendent assigned to the job be present at the interview. (The executive represents the company, the manager spends the owner's money and the superintendent is the on-site contact.) Closely observe the interaction between these people. A successful project can hinge on the working relationship between them.

Require all interviewing CMs to submit a detailed account of what they heard and agreed to at the interview. This important document will reflect the CM's understanding of your conditions and form the basis for contract negotiations. This document will also serve to suppress potential disputes arising from construction contract issues.

Where costs hide

The construction contract between the owner and CM is a legally binding contract but its terms are not universal. The owner should negotiate the specifics of the contract requirements and the particular needs of the project.

The more knowledgeable the owner - often represented by the facility executive - is about the nature of the terms of the contract, the greater the awareness of the potential for hidden costs. Uninformed owners can unwittingly agree to pay more money for a longer period of time than necessary.

Demonstrate your understanding of the construction process by first knowing the unit prices and labor costs of every item you agree to purchase and negotiating the following standard construction contract line items.

• General Conditions. General Conditions should only be those non-construction costs that are necessary to get the job done and are directly applicable to the project. All general conditions should be a line item amount agreed to and guaranteed before the start of construction. Typical components of general conditions include funds for a site office, on-site project administration labor and necessary office equipment. Do not accept an amount that is expressed as a percentage of the cost.

Substantial savings can be realized by asking the right questions about general conditions. For example, question the site office requirements presented by the CM, including how much new equipment is necessary. Who should assume the cost of purchasing and installing the computer equipment and software the CM lists as a site office requirement?

• Overhead. Overhead is the CM's cost of doing business. Should the owner be responsible for that cost? An argument can be made that the owner need only pay for costs directly applicable to this specific project, and not for costs the CM incurs on other jobs. This line item in particular is often the subject of legal disputes. Do not be afraid to eliminate elements of cost contained in this category and, again, do not accept an amount that is expressed as a percentage of the work.

• Hourly Wages. Agree to pay only the wages for work on your project. The actual hourly wages, taxes and benefits (not a multiple of these) are the owner's responsibility. Time off and educational seminars are not. Avoid a situation where you are asked to pay wages for a general superintendent or any other part-time supervisory personnel.

• Construction Fees. To determine a fair construction fee, negotiate a percentage based only on the cost of the work. Be careful of the language of the contract. All fees are a direct percentage of the cost of the work, before the contingency and general conditions are added. A fair 4 percent construction fee could be 4.5 percent if taken as a percentage of a cumulative total. On multi-million dollar jobs, this can represent a substantial amount of money.

Insist that the fee be converted from a percentage to a fixed amount before construction starts. Once construction starts and the potential for change orders (that can increase the cost of the work) exists, the fee will continue to rise without limit. Don't allow the construction budget to be compromised in this way.

• Contingency Fee. Most CMs require that a contingency fee be built into the guaranteed maximum price. The only responsible way to manage the necessary contingency fee is to insist that it be jointly controlled by the owner and the CM. Neither the design nor the construction process is a perfect science; CMs will insist that they need to "manage their risk" with the contingency fee. Maintaining some control over the allocation of funds will enable the owner to best justify the expenses.

When negotiating the contract, the owner must "buy the schedule" with the cost of construction and guard against it slipping. Extending the construction phase is a costly decision.

Agree on the completion date of the project and insist that a penalty be levied if the project is delayed. Do not agree, however, to a bonus if the project is finished before the scheduled delivery date. The CM might deserve a bonus for early delivery if extraordinary problems were overcome, but does not necessarily deserve bonus dollars for performing the job you hired them to do.

Change orders and substitutions

In negotiating the change order procedure in the construction contract, the owner should demand a "no work stoppage" clause. Too much time can be wasted if work ceases in anticipation of a general agreement of change order amounts and schedule implications.

When presented with a change order, the architect should consider both the money and time the CM is looking to add to the job. Each is open for discussion. Don't wonder why construction isn't finished and then discover the architect has authorized an additional week of accumulated change orders.

While the CM should aggressively pursue reasonable substitutions on your behalf, be sure you or your architect knows the cost of the originally specified product and the cost of the alternative. The construction contract should state clearly that cost savings realized by the substitution for a specified product go directly to the owner. Here, too, substantial savings can be realized.

As your architect's last element of control over the quality of the project, the punch list must be a thorough process. Accompany the architect to look at the job. Try to anticipate any problems that may arise once the space is occupied. If a fault is discovered after the owner has released the CM, the issue will be more difficult, time consuming, and expensive to remedy.

Secrets of a successful renovation

To successfully manage a renovation process while the facility remains in operation, consider the following ways to minimize cost and disruption:

• What you see is not what you get. In most cases, the older the building you are occupying and renovating, the greater the potential discrepancy between the budgeted and actual costs of the renovation. Work with an architect and a CM who have enough renovation experience to anticipate potential unforeseen elements (electrical, mechanical, environmental and code compliance) and to quantify the cost of the work before the construction contract is signed.

• Designating a "swing space." If your project requires renovating existing spaces while you are occupying them, provide a "swing space" for temporary use by each displaced department as its permanent space is modified. To determine the order in which the areas are renovated, consult with department managers and the CM to minimize the disruption to company productivity and maximize the efficiency of the renovating and moving processes.

• Building a "smart" addition. If your renovation includes building an addition onto the space you are occupying, minimize traffic, dust and noise by building as much of the addition as possible before breaking through to connect with the existing spaces.

• Establishing a presence. As the facility manager, your knowledge of the facility and daily operations makes your presence in the process invaluable. Attend weekly construction meetings and address issues before they become magnified and more costly. Often, because of your vast knowledge of the building and its systems, you will understand the issues and can offer a workable solution more readily than the construction team.

Opening the lines of communication

Precise communication with all of the individuals involved in the process, especially the clients you service and the employees who must be accommodated, is essential. One extreme case - the renovation of a hospital emergency room - demanded the cooperation of the local police, ambulance services, and other area hospitals to reroute and accept patients.

Common scenarios involve notifying staff of an activity or a move (start date, duration, specifics), discussing the arrangement for temporary facilities, ensuring safety and security, and providing additional signs to redirect visitors. The more accurate the construction schedule and the more open the lines of communication, the more efficient and less expensive the process.

Weekly progress coordination meetings should be attended by building administrators, maintenance and engineering staffs, and each subcontractor to review progress. Detailed meeting minutes should be distributed both internally and to the appropriate regulatory officials. These minutes will be the core documentation vehicle for the project.

Not every owner or facility manager has the time, interest or expertise to devote to project management.

The owner can still protect his or her interests by hiring an advocate to coordinate and oversee the construction process. As the owner's representative, this individual defines the development process, negotiates project contracts, schedules and monitors all stages of the construction process, and coordinates communication between participants.

The fee for this service can be offset by substantial savings in construction costs. Many clients hire these experts to "fix" a project that is already in trouble, but an advocate is most valuable if consulted from the start.

Julian Arhire is a Manager with DtiCorp.com - DtiCorp.com carries more than 35,000 HVAC products, including industrial, commercial and residential parts and equipment from Honeywell, Johnson Contols, Robertshaw, Jandy, Grundfos, Armstrong and more.

Investing In A High-Quality Roofing System

Owners who view the roofing system as a one-time expense, and make specification decisions based solely on first costs, run the risk of incurring higher roof maintenance and repair expenditures. The bottom line: Selecting the wrong system is likely to cost a facility executive significantly more than if the right system had initially been selected.

High repair costs can be avoided by installing a high-performance roofing system and conducting routine preventive maintenance throughout the life of the roof. The first cost of a quality roofing system may be higher, but the lower life-cycle costs of the system will more than offset the initial investment.

The initial cost of a roofing system includes materials, labor, overhead, profit and indirect costs associated with the structure. The life-cycle analysis takes the first cost of the roof, then adds to it the future costs of operation and maintenance over the economic life of the roof.

The facility executive that fails to consider the value of a life-cycle costing approach to the purchase of a new roof does the facility and everyone involved with it a financial disservice. First-cost buyers may overlook such important future expense reduction opportunities as:

• Energy cost savings in the heating and air conditioning of the building through the use of white, reflective membranes or coatings and extra insulation.

• Extended roof service life for an optimally drained roof.

• Enhanced roof fire retardence and wind uplift resistance, resulting in reduced insurance costs.

• Extended roof service life resulting from the use of heavier structural framing materials, allowing a heavier roofing system.

• Future savings when the roof is to be replaced by using reusable roof component accessories.


• Reduced roofing surface repairs through installation of a heavier membrane of walkway pads for high-traffic roofs.

• Prevention of roof surface degradation in those roof areas where harmful emissions may occur by installation of appropriate protective devices.

The most cost-effective roof is one that will stand up to the elements and demands of time. Therefore, facility executives should be actively involved in the initial planning stages to determine the best roofing system based on the established criteria for the building.

Planning and Specification

Make sure the roofing system will meet the needs of the facility by answering the following questions:

• What type of system will provide the best long-term performance and energy efficiency?

• How will weather conditions and climate affect the building and roof?

• What is the desired service life of the roof?

• Is resale value of the building important?

• What type of system will incorporate the best drainage characteristics?


• What type of maintenance program will be followed?

• What are the expectations for the roof?

• Are there environmental concerns?

• Does the roof need to be wind- and fire-rated?

Once these questions have been answered, start the selection process based on location, physical characteristics, and building structure and type. Then choose quality products specifically engineered to be integrated and installed as a complete roofing system. To do this, form long-term relationships with manufacturers that are financially sound and have a reputation for commitment and experience in the marketplace. Check the track record of suppliers, as well as the quality controls they provide during installation.

Life-cycle costing analysis doesn't do any good if the facility executive chooses a manufacturer that is unable to demonstrate financial stability, experience and roofing system longevity.

Successful roofing installations also depend on the expertise of a quality-focused, professional roofing contractor.

Many times, roofing is specified just to get the building covered and protected. Facility executives should realize that the majority of the cost is in labor. Slightly more material dollars up front may save many dollars on premature replacement costs.

It's also important to remember the role of the roof as the first line of defense against the elements. The roofing system is a key investment that helps to protect the interior environment of the building. Focusing on the lowest initial cost can leave facility executives with a system that is unproven and contributes to further difficulties during the life of the building.

Although the roof makes up less than 3 percent of the construction cost of a commercial building, it is among the most critical construction components, considering the consequences if it fails.

When the facility has as its basic purpose the protection of not only humans involved in daily commerce, but also valuable business assets that are critically important to the conduct of that commerce, the roof emerges as more than a cost component of the total building asset - it becomes an asset in and of itself.

The key to life-cycle cost is total system analysis. A roof is a system that requires a broad spectrum of elements working together. When a building owner chooses an asphalt roofing system for a given application, the system should be specified and installed as a whole. The performance of any roofing system can be optimized when all the components are selected based on how they integrate as part of a total roofing system.

A Whole System Approach

As with any investment, the ultimate value of the roof will be determined in large part by the investment term. In this case, the term is the realistic, anticipated life of the new roofing system. The best way to determine how long a roofing system is likely to last is to consider the documented performance of the system in similar applications and environments.

The value of a roof can actually increase if it survives its first few years without incident. A life-cycle curve often has a bump for premature mortality. If a roof survives past the time period of that bump, then the long-term outlook actually improves.

Calculating Life-Cycle Cost

A general formula for calculating the life-cycle cost of a roof is to subtract the estimated salvage cost of the new roof materials from the purchase price and then add the projected costs of maintenance, repair and replacement over the forecasted economic life of the roof. For this calculation, the value of today's dollar must be converted to a future value.

Energy efficiency has become a significant factor in determining a roof's life-cycle cost. Many facility executives are specifying metal-clad or coated modified bitumen membranes and flashings, other reflective membranes or additional insulation as energy-efficient options. A variety of aluminum or white acrylic coatings can be applied to smooth surfaces. Granule-surfaced modified bitumen membranes can be applied to enhance reflectivity. By improving the energy efficiency of the building with reflective membranes or additional insulation, facility executives can often reduce cooling costs.

Before problems occur, preventive maintenance should also be conducted to remove visible debris from the roof, clean drains and perform minor repairs. No matter how thorough the maintenance program is, however, it is necessary to make routine, semi-annual inspections to reduce long-term repair costs. At a minimum, facility executives should have their roofs inspected once in the spring and once in the fall.

The eventual tear-off and disposal of the roofing system is another necessary factor to be included in the life-cycle cost. Some systems require a more labor-intensive removal process, which can add to the total cost, while certain membrane types can be recycled, which may ultimately reduce the cost of the system.

Seek Help

With the wide range of system types available in today's commercial roofing industry, one of the main obstacles facility executives encounter is acquiring the knowledge necessary to make informed decisions. Manufacturers offer seminars that allow facility executives a forum in which to expand their knowledge base and understanding. Once owners have the information necessary to make sound specification decisions, they can confidently specify roofing products and systems that will meet their long-term goals.

Julian Arhire is a Manager with DtiCorp.com - DtiCorp.com carries more than 35,000 HVAC products, including industrial, commercial and residential parts and equipment from Honeywell, Johnson Contols, Robertshaw, Jandy, Grundfos, Armstrong and more.

Blueprint for Energy Cost Control

Despite the importance of planning in facility operations, too many facility executives abandon it when managing energy use. Instead, they undertake a series of uncoordinated activities that typically include equipment upgrades, system replacements and energy services contracting. In some cases, specific steps may even prove to be counterproductive. Too often, these measures simply mirror what other facility executives are doing without considering the needs of a particular facility. Implementing one "energy project of the month" after another may reduce the use of energy, but it isn't energy management.

While energy conservation measures implemented without an overall plan reduce energy use and costs, they do so with an unequal impact. Since energy conservation budgets are not unlimited, facility executives need to implement those that produce the most favorable returns in terms of energy and cost savings for a given investment in a given facility.

Another problem with not having an energy management plan is missed opportunities. One of the key elements in an energy management plan is the identification of when, where and how much energy is used in the facility. Successful programs identify big energy users and focus efforts on them. Without that step, facility executives can't know what measures will produce the best results.

Lack of an energy conservation plan also leads to uncoordinated - and often counterproductive - efforts. For example, installing high efficiency central chillers will improve the overall efficiency of the chiller plant, but under electricity deregulation, the installation of an alternative drive chiller, such as an absorption chiller or engine-driven centrifugal chiller, might reduce costs even more. Or upgrading to T8 lamps and electronic ballasts without first considering the lighting needs of the space may result in inefficiencies due to the overlighting of some areas.

Finally, lack of an energy conservation plan places the facility in a position where it must react to rather than anticipate marketplace changes in the supply and cost of energy. For example, deregulation is giving facilities the incentive to flatten electrical loads. Facility executives who have developed an energy management plan already know how their electrical loads vary with the time of day and the season of the year, so they are able to take steps to reduce load peaks.

Once the loads have been reduced, facility executives can further reduce their electrical load during periods of high rates by, for example, installing engine-driven chillers or gas-fired absorption chillers. Without an energy conservation plan already in place, facility executives would have little time to react to the changes introduced by deregulation.

A facility's energy management plan is a road map to efficiency. The plan identifies where the facility is currently in terms of energy efficiency, where the facility needs to be and how it is going to get there. To make the plan successful, it must include all three elements. Skipping one or more may save time, but it will not allow a facility executive to manage energy use.

The energy management plan also should be flexible and able to respond quickly to changes in the marketplace. As facility executives have seen over the past year, the energy industry is volatile, with electricity price spikes, heating oil shortages and price instability.

Finding Out Where You Are

Before a plan can be developed to manage energy use, the facility executive must understand how energy is used in a facility. What types of energy sources are used? How much does the facility use? When does the use take place? Where is the energy used? Why?

Understanding energy use in the facility is the first step in developing an energy management plan, but this alone does not tell facility executives where they are. A facility might be highly energy efficient, or it might be an energy hog. Without a base of comparison, the facility executive will not know where a facility stands or how much opportunity exists for improvement.

One method that can be used to help develop that understanding is benchmarking. Benchmarking compares the energy use in a given facility to the energy use of other similar facilities. Facilities can be benchmarked against published building energy use data. One source for published energy use data is the U.S. Department of Energy's Commercial Buildings Energy Consumption and Expenditures. Listing energy use on a Btu per square foot basis for a wide range of facilities in different climates, the published data can be used to show where a particular facility stands in terms of energy efficiency relative to other similar facilities.

For office buildings and K-12 school facilities, EPA's Energy Star Label for Buildings program has developed an online energy benchmarking tool. The tool takes into account differences in factors like location and hours of operation and ranks a building on a scale of 1 to 100 for energy efficiency.

Another method of benchmarking is to compare energy use in a given facility to the measured energy use in other similar facilities, particularly if those facilities are considered to be among the best in a class when it comes to energy efficiency. One must be careful, though, to compare only facilities that are truly similar. Differences in how the facility is used, the hours of operation and the energy-using systems will result in invalid comparisons.

By determining the energy use pattern for the facility and comparing it to that of other similar facilities, facility executives can determine how energy efficient their operation is and how much room exists for improvement.

Identifying Opportunities

The information gathered when identifying energy use patterns of the facility can be used to help identify energy conservation opportunities. Those patterns will show areas where energy use and costs are the highest and therefore offer the greatest potential for savings.

In identifying opportunities for energy conservation, savings estimates must be developed for each item being considered. Those estimates can be used to determine the payback for the items, allowing comparisons to be made on the basis of savings produced and return on investment.

Deregulation is generating additional opportunities for energy management and an even greater need for an energy management plan. Facility executives that have in place an energy management plan that takes into consideration the impact and requirements of electricity deregulation will be able to take advantage of the opportunities it creates. Those that don't will end up paying higher rates for electricity - often higher than they were before deregulation.

One of the key areas that must be addressed by the energy management plan under deregulation is real-time pricing. Under deregulation, electricity rates will vary by the hour based on a number of factors, including the total demand for electricity and what it costs the utility to meet that demand. As the demand increases, so will the cost of electricity. While the implementation details of how real-time pricing are still being worked out, real-time pricing's impact on the cost of energy to facilities will be significant. Already, some users have found that the cost of electricity during periods of high demand has increased by a factor of between 25 and 100.

Setting Priorities

Identifying opportunities tells a facility executive what can be done to reduce energy use but not which energy conservation activities should be completed first. Because the number of identified activities always exceeds the available funding, priorities will have to be established. There are several ways to establish priorities, including payback, load reduction factors and need.

Payback is the most common method. Although many different variations of payback calculations have been used to evaluate energy projects, all look at the expense of implementing the project and the savings that will be produced. Those that offer the highest rate of return are typically selected first for implementation.

Sometimes, producing the quickest payback is not the best way to go. In general, the greatest potential for energy savings in facilities lies in that facility's major energy-using systems: the chillers, cooling towers, boilers and lights. If large savings are needed in a short period of time, then the big systems are the ones to start with. Because of their high energy use, even relatively small improvements in operating efficiency can result in large savings. However, if the goal of the energy conservation program is to achieve the highest energy efficiency possible, then it is best to start by minimizing building loads at their source first.

Addressing building cooling loads at their source reduces the load on central equipment, such as building chillers. When it comes time to upgrade those central chillers, smaller units can be installed. Those smaller chillers will be more closely matched to the actual building cooling loads than if the chillers had been replaced before loads were reduced. Matching chiller capacity to actual cooling loads allows chillers to operate more efficiently, saving energy.

There are times when a project's payback is secondary to the need to reduce energy use. When a facility is facing a shortage or a curtailment, payback is not as important as achieving a reduction in use. For example, the past two summers have seen high demand for electricity in some regions of the country, demand so high that utilities have ordered cuts in electricity use in order to prevent possible widespread power outages. Faced with the alternative of reducing use or losing electrical service, facilities have taken steps to curtail their demand. These steps can be implemented effectively only if they have been planned ahead of time. When the utility is on the phone demanding a 5 or 10 percent reduction in electrical demand, it is too late to begin looking for electrical loads that can be reduced.

The energy management plan should include items that can be implemented in short order. These items may cause some level of disruption in operations, and they may not be fully cost effective, but in situations where significant load reductions must be rapidly achieved, they may be the only alternative to loss of service or severe economic penalties.

Most facilities have the potential to reduce energy use between 25 and 50 percent through upgrades to existing energy-using systems, changes in the way existing systems are operated and improvements in maintenance practices. Some measures will require significant investments in new equipment. Others will require simple operational changes and attention to details. But the programs that will be most effective are those that examine all options and carefully lay out a plan for managing energy use.

7 New Honeywell 914CE Micro Switch Limit Switches From DtiCorp.com

Fort Lauderdale, FL - Popular Honeywell online retailer DtiCorp.com (http://www.DtiCorp.com) is introducing 7 brand new Honeywell 914CE Micro Switch Limit Switches. All MICRO SWITCH 14CE and 914CE series miniature enclosed switches incorporate fluorocarbon diaphragm sealing to provide reliable protection, meeting NEMA 1, 2, 3, 3R, 4, 6, 6P, and 13 as well as IP66, IP67, and IP68 requirements. Versions with boot seal also meet NEMA 12 requirements (dust, falling dirt, liquid media with solid contaminates). The cable or connector and basic switch terminals are encapsulated in an epoxy compound, offering superior resistance in harsh environments. For low temperature applications (down to -40 degrees C, -40 degrees F), CE switches can be supplied with low temperature seals and lubricant.

The CE switches are a rugged and versatile switch which can be applied indoors in harsh factory floor applications, as well as on outdoor equipment in extreme temperatures. A full range of actuators are available, including plain plungers, roller plungers, side rotary, multi-directional wire, and manually operated. The switches are also available with the industry standard, M12 miniature 4-pin connector. The MICRO SWITCH 14 CE versions are designed for European applications and meet the requirements of the low voltage directive and therefore carry the CE mark. The MICRO SWITCH 914CE products meet UL and CSA standards, as well as European CE requirements.

Features:

- Sealing: IP65, IP66; NEMA 1, 3, 4, 6, 6P, 12, 13

- Temperature range: 0 °C to 70 °C [35 °F to 160 °F]

- Housing material: zinc die-cast

- Actuators/levers: side rotary, top plunger, roller, pushbutton, wobble

- Termination: cable, micro-connector

- Approvals:

- 14CE: CE, IEC947-5-1, EN60947-5-1

- 914CE: UL, CE, CSA, IEC947-5-1, EN60947-5-1

- Circuitry: SPDT, SPSTNC, SPDTMBB, SPDTBBM

- Contacts: silver, gold

- Amp rating: 5 A (thermal)

- Measurements: 49 mm x 40 mm x 16 mm

Applications:

- Processing Equipment

- Textile Machinery

- Machine Tools

- Robotics

- Packaging Equipment

- Farm Machinery

- Commercial Laundry Equipment

- Printing Trade Machinery

- Vehicles

Models Available:

1. Honeywell 914CE1-Q1 Micro Switch

2. Honeywell 914CE1-Q Micro Switch

3. Honeywell 914CE1-9 Micro Switch

4. Honeywell 914CE1-6A Micro Switch

5. Honeywell 914CE1-6 Micro Switch

6. Honeywell 914CE1-3A Micro Switch

7. Honeywell 914CE1-3 Micro Switch

About Us: DtiCorp.Com (http://www.DtiCorp.com) carries more than 35,000 HVAC products, including industrial, commercial and residential parts and equipment from Honeywell, Johnson Contols, Robertshaw, Jandy, Grundfos, Armstrong and more. Our online catalog is easy to navigate and search, and all products have a picture and a description. If a customer has any questions about a product, they can call 800-757-5999 and speak with one of our product experts. Our mission is to offer the best prices anywhere to our customers.

Julian Arhire

Manager DtiCorp.com

Phone: 954.298.2515

Fax: 954.206.0767

Web: http://www.DtiCorp.com

Taking Charge of Indoor Air Quality (IAQ)

As sick buildings become more visible, inaction is a liability. This situation begs the question: "Will you be ready when dissatisfied occupants, reporters and lawyers show up at your building?" As part of an overall preventive due diligence program, an IAQ audit can show good faith and quality management.

Making headlines

Most publicized incidents involving IAQ problems have involved moisture and microbial problems. For instance, an employee in a branch of the New York Library complained of respiratory illness. Even though the library had undergone an extensive renovation a few years earlier, basement flooding problems persisted.

A consulting group was brought in to investigate, and found a mold - Stachybotrys atra - that has been implicated in numerous sick buildings. The exact health effects of this mold are not clear, however. The building was closed, and other library branches were investigated. As a result of these additional investigations, two other branches were closed.

IAQ audit

An IAQ audit involves periodic inspection of an IAQ program to ensure practices are carried out and procedures are followed. In its simplest form, it involves a visual inspection of the building and its HVAC system components. A more comprehensive audit includes this inspection, along with a review of a building's:

• design documents


• training program

• written IAQ plan, including policies and procedures

• on-going documentation, such as complaint reports and maintenance records

• any IAQ or medical reports.

Fortunately, many useful resources exist to facilitate the audit process. For commercial buildings, the EPA's Building Air Quality guidance document contains blank forms that can be used to structure and conduct an audit. For educational facilities, EPA's IAQ Tools For Schools guidance kit contains practical checklists that can be used in an audit. An audit template accompanies this article on page 9, but any checklist used should be tailored to a building's specific needs.

Typical legal scenario

No legally established definitions exist as to what constitutes "good" IAQ in terms of design, operation and maintenance of HVAC systems or controlling indoor air contaminants. What should maintenance and engineering managers do to provide a healthful indoor air environment, given the lack of definitive standards?

Managers should base their conduct on industry standards developed by organizations such as the EPA, the Occupational Safety and Health Administration (OSHA), and the American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE), since the courts turn to these sources for guidance.

If managers can show that they are making a good-faith attempt to manage their facilities according to prevailing standards, their legal exposure to IAQ litigation will be minimized. How do managers show a judge or occupant they are making such an attempt? Documentation is key.

Building audits are an important process that managers should perform consistently in the course of building management. Aside from ensuring IAQ, audits can create necessary documentation to demonstrate good-faith IAQ efforts. A quality building audit provides a manager with tangible evidence that the building and its components have been assessed for current problems.

Regular building audits, much like regular medical check-ups, are preventive. They indicate a diligent, rather than an indifferent, management style, which can minimize legal exposure.

Air quality improvement

Maintenance and engineering managers need to meet rising occupant expectations each day, and they need to show a concerted effort is under way to maintain acceptable IAQ. Essentially, this is the concept of continuous quality improvement being applied to buildings: the air quality improvement process.

An IAQ audit can be a useful tool for isolating the areas on which management should focus. IAQ audits can pinpoint potential areas of concern, areas where preventive efforts are successful, areas that require the establishment of policies and procedures and areas where staff training is needed.

Implementation tips

The most effective way to start an audit program will depend upon a facility's in-house maintenance and engineering expertise. If a building's staff is well trained in IAQ and experienced with buildings and HVAC systems, managers can customize a checklist for the building, and audits can be performed periodically -at least once a year.

If in-house expertise does not exist, a consultant can be brought in to conduct the audit. During this third-party audit, appropriate personnel should accompany the consultant to learn how to conduct the audit themselves. It may be helpful to use photographs to document observations of the building and HVAC system.

The auditing process and the resulting observations can serve as a valuable training tool for all those charged with IAQ responsibilities.

After any audit, the auditor should brief members of the IAQ team on the resulting observations and suggestions. Managers should retain the completed audit checklist for future reference, and they should address problems in any areas that require corrective action, making sure to document the process.


With the increase in sick building visibility, inaction is a liability. After all, you never know when your IAQ might start making headlines.

The Elements Of An Efficient HVAC System

Today's systems are designed to meet stricter environmental, indoor air quality and user requirements. Many of the gains in HVAC system efficiency have come as the result of improvements in the operating efficiency of key system components. Other gains are the result of the use of technologies that are either new, or new to the HVAC field. Even the use of computer-aided design tools have helped system engineers design HVAC systems that perform more efficiently.

Although there are many individual advances that have helped to improve HVAC system operating efficiency, much of the overall improvement can be attributed to five key factors:

- The development of low kW/ton chillers;

- The use of high-efficiency boiler control systems;

- The application of direct digital control (DDC) systems;

- The use of energy-efficient motors; and,

- The matching of variable frequency drives to pump, fan and chiller motors.

For years, building owners were satisfied with the performance and efficiencies of chillers that operated in the range of 0.8 to 0.9 kW/ton when new. As they age, actual operating efficiencies fall to more than 1.0 kW/ton at full load.

Today, new chillers are being installed with full load-rated efficiencies of 0.50 kW/ton, a near 50 percent increase. Equally impressive are the part-load efficiencies of the new generation of chillers. Although the operating efficiency of nearly all older chillers rapidly falls off with decreased load, the operating efficiency of new chillers does not drop off nearly as quickly.

Chiller design changes

Several design and operation changes have helped improve chiller performance. To improve the heat transfer characteristics of the chillers, manufacturers have increased the size of the units' heat exchangers. Electromechanical control systems have been replaced by microprocessor-based electronic controls that provide greater precision, reliability and flexibility. Variable frequency drives control the speed of the compressor, resulting in an increase in part-load performance.

Increased energy efficiency is not the only benefit of the new generation of building chillers; these chillers offer better refrigerant containment. Although older chillers routinely may have lost 10 percent to 15 percent of the refrigerant charge per year, new chillers can limit losses to less than 0.5 percent. Lower leak rates and better purge systems reduce the quantity of non-condensable gasses found in the refrigerant system -- a key factor in maintaining chiller performance over time.

Another significant development is in boiler operation: the replacement of pneumatic and manual controls with microprocessor-based systems. As a rule of thumb, the systems can be expected to achieve energy savings of 5 percent to 7 percent over conventional pneumatic-based systems.

Microprocessor-based control systems achieve their savings primarily as the result of their ability to modulate the boiler's operation more accurately than pneumatic-based systems. By modulating the boiler's operation accurately, the systems help to maintain the proper fuel-to-air ratio and track the load placed on the boiler by the HVAC system.

Microprocessor-based systems offer several additional advantages, including remote monitoring and operating capabilities, automated control sequences, monitoring of steam flow, and reduced maintenance costs. One way the systems can help reduce maintenance costs is through their ability to maintain proper fuel-to-air ratio. By maintaining the proper ratio, the systems reduce the rate at which soot collects on boiler tubes, thus decreasing the frequency of required tear down and cleaning. Keeping the boiler tubes clean of soot also helps to improve the thermal efficiency of the boiler.

Direct digital controls

A major change in the HVAC field is the widespread implementation of direct digital controls (DDC). Introduced more than 15 years ago, DDC systems have become the industry standard for control systems design today. With the ability to provide accurate and precise control of temperature and air and water flows, the systems have widely replaced pneumatic and electric control systems.

DDC systems help building owners save energy in several ways. Their accuracy and precision nearly eliminate the control problems of offset, overshoot, and hunting commonly found in pneumatic systems, resulting in better regulation of the system. Their ability to respond to a nearly unlimited range of sensors results in better coordinated control activities. This also allows the systems to perform more complex control strategies than could be performed with pneumatic controls. Finally, their simple or automatic calibration ensures that the control systems will perform as designed over time, with little or no loss of accuracy.

DDC systems also offer several other advantages. Because the control strategies are software-based, the systems can be easily modified to match changes in occupant requirements without costly hardware changes. DDC systems also are ideal for applications that benefit from remote monitoring and operation.

Energy-efficient motors

Today's HVAC systems are making use of energy-efficient motors. Energy-efficient motors offer a moderate but significant increase in full-load operating efficiency over standard motor designs. For example, an energy-efficient 10 hp motor operates at about 93 percent efficiency; a standard motor of the same size is typically rated at 88 percent. Similarly, a 50 hp energy-efficient motor is rated at approximately 94 percent efficiency in contrast to the 90 percent efficiency rating of a 50 hp standard motor.

This increase in operating efficiency accompanies a first-cost increase for the motors. How rapidly this additional first cost is recovered depends on two factors: the loading of the motor, and the number of hours the motor is operated per year.

The closer the motor is operated to its full-load rating and the greater the number of hours per year the motor is operated, the quicker the first-cost differential is recovered. For most applications where the motor is run continuously at or near full load, the payback period for the additional first cost is typically between three and six months.

The combination of constant loading and long hours of operation have made HVAC applications well-suited for the use of energy-efficient motors. Energy-efficient motors commonly are found driving centrifugal circulation pumps and system fans. With these loads, the 4 percent or 5 percent increase in the electrical efficiency of the drive motor translates to a significant energy savings, particularly when the systems operate 24 hours per day, year round.

A side benefit of energy-efficient motor design is its higher power factor. Increasing the power factor of a drive motor reduces the current draw on the electrical system, frees additional distribution capacity and reduces distribution losses in the system. Although increasing the power factor isn't enough of a benefit to justify the cost differential of the higher efficiency motor, it's an important consideration, particularly for large users of electricity where system capacity is limited.

Although the motors have demonstrated themselves to be very cost-effective in new applications, their use in existing applications is a little more difficult to justify. In most instances, the cost to replace an existing, operating motor with one of higher efficiency will not be recovered for five to 10 years or longer.

Of the improvements in HVAC systems that have helped to increase operating efficiency, variable frequency drives have had the most dramatic results. Applied to system components ranging from fans to chillers, the drives have demonstrated themselves to be very successful in reducing system energy requirements during part-load operation. And with most systems operating at part-load capacities 90 percent or more of the time, the energy savings produced by variable frequency drives rapidly recover their investment, typically within one to two years.

In general, the larger the motor, the greater the savings. As a rule of thumb, nearly any HVAC system motor 20 hp and larger can benefit from the installation of a variable frequency drive.

Variable frequency drive applications

Variable frequency drives produce their savings by varying the frequency and voltage of the motor's electrical supply. This variation is used to reduce the operating speed of the equipment it controls to match the load requirements. At reduced operating speed, the power draw of the drive motor drops off rapidly.


For example, a centrifugal fan, when operated at 75 percent flow, draws only about 40 percent of full-load power. At 50 percent flow, the power requirement for the fan decreases to less than 15 percent of full-load power. While conventional control systems, such as damper or vane control, also reduce the energy requirements at partial flow, the savings are significantly less.

Another area where variable frequency drives have improved the operating efficiency of an HVAC system is with centrifugal pumps found in hot and chilled water circulation systems. Typically, these pumps supply a constant flow of water to terminal units. As the demand for heating or cooling water decreases, the control valves at the terminal units throttle back. To keep the pressure in the system constant, a bypass valve between the supply and return systems opens. With the flow rate remaining nearly constant, the load on the pump's electric drive also remains nearly constant.

Variable frequency drives regulate the pressure in the system in response to varying demands by slowing the pump. As with centrifugal fans, the power required by the pumps falls off as the load and speed are decreased. Again, because most systems operate well below design capacity 90 percent of the time, the savings produced by reduced speed operation are significant, typically recovering the cost of the unit in one to two years.

Chiller loads

A third application for variable frequency drives is centrifugal chillers. Chillers are sized for peak cooling loads, although these loads occur only a few hours per year.

With conventional control systems that close vanes on the chiller inlet, chiller efficiency falls off significantly during part-load operation. When variable frequency drives are applied to these chillers, they regulate the operation of the chiller by reducing the speed of the compressor. The result is near full-load operating efficiency over a very wide range of cooling loads. This increase in part-load efficiency translates into a 15 percent to 20 percent increase in the chiller's seasonal efficiency.

Energy conservation isn't the only benefit of variable frequency drives. A strain is placed on an electric motor and the mechanical system it drives every time a pump, fan or chiller is started at full-line voltage: Motor winding becomes heated, belts slip, drive chains stretch and high-pressure is developed in circulation systems. Variable frequency drives reduce these stresses by starting systems at reduced voltages and frequencies in a soft start, resulting in increased motor and equipment life.

Finally, the most important element in an energy-efficient HVAC system is how the system is operated. No matter how sophisticated the system, or how extensive its energy-conserving features, the system's performance depends upon the way in which it's operated and maintained. Operating personnel must be properly trained in how best to use the system and its features. Maintenance personnel must be trained and equipped with the proper tools to keep the system operating in the way it was designed. Maintenance cannot be deferred.

Energy-efficient HVAC systems offer the facility manager the ability to improve system performance while reducing energy requirements. But they benefit building owners only as long as they are taken care of. If facility managers choose to ignore maintenance requirements, they may soon find systems malfunctioning to the point where they have actually increased the requirement for energy.

Healthcare And Facility Infrastructure

New diagnostic and treatment equipment occupies dedicated spaces. At the same time, there is increased emphasis on ambulatory care for many procedures and illnesses, with more selective inpatient admissions and decreased length of stays. There also is a trend toward networking remote primary care and diagnostic centers to other types of care facilities.

With these changes comes the need to provide more sophisticated HVAC, power, telecommunications/data and life safety systems. Owners, architects and engineers alike face the challenge of allocating space and developing a facility infrastructure that not only accommodates these systems but also allows optimal integration and flexibility today and in the future.

To meet the demands placed on system infrastructure and to provide future flexibility, space must be allocated for much larger mechanical, electrical and telecommunications distribution hubs and risers. One of the biggest problems in existing facilities, which may be 30, 40 or 50 years old, is finding and reprogramming enough space to revamp the entire core infrastructure and controls. In new facilities, owners may be understandably reluctant to add to the amount of space required for the engineering systems.

Indeed, the proportion of the cost of the building systems to the total cost of a new facility is now approaching 50 percent. Whether planning an upgrade or new construction, finding cost-effective solutions requires cooperation among owners, architects and engineers.

Optimizing the HVAC System

Energy efficiency, indoor air quality, comfort and flexibility for future changes are the key criteria to keep in mind when engineering the HVAC system, which must provide the optimal environment for a range of treatment and support spaces.

HVAC systems today comprise more individual units dedicated to meeting the different temperature and air-quality needs of spaces such as telecommunications/data equipment rooms, diagnostic equipment rooms, operating rooms, emergency rooms and in-patient rooms. Zoning also allows the mechanical engineer to employ specific tools, such as high-efficiency air filters, where they are needed.

To assure indoor air quality, the HVAC system must be able to provide proper filtration and ventilation, and minimize cross-contamination of building spaces. Airflow must be directed from clean areas to less clean spaces and then exhausted outside. Controls must use a reliable monitoring and alarm system to ensure maintenance of proper indoor air quality and pressurization standards.

"All-air" HVAC systems, which allow use of primarily outside air to, whenever possible, heat and cool a facility, enhance indoor air quality and the energy efficiency of the HVAC system. Efficient motors, variable speed drives and economizer cycles all can be used to minimize energy consumption.

In any case, HVAC systems are heavy energy consumers. But deregulation has provided the opportunity to use systems that can use multiple energy sources to run boilers and produce chilled water. At any given time, the facility can choose which energy source to use (electricity, natural gas or steam) depending on demand, cost and availability.

The nature of today's hospital demands selection of state-of-the-art direct-digital-controlled HVAC systems, which are accurate and flexible, allowing control from central and remote locations.

Power: Quantity and Quality

Flexibility of power system infrastructure and power quality are key criteria for the electrical power system design. Spare capacity has to be built into every major normal and emergency power riser. In most cases, minimum code-suggested values for feeder and equipment sizing may not be adequate for modern hospital design because of universal usage of computer equipment for a wide variety of functions.

The nature and sheer volume of hospital systems and equipment also create challenges. For example, more and more equipment today is electronic, which contributes distortion to the electrical system. Current causes this distortion and voltage harmonics that affect both normal and emergency power supply and distribution systems, and sensitive medical electronic equipment fed from it.

To minimize harmonic effects on the power system, 200 percent neutral should be the standard on all three-phase, four-wire systems and equipment. Rectifiers and trap filters are strongly recommended on all variable frequency drives. Emergency generator specifications have to include provisions for 100 percent non-linear loads. Usually, generators will have to be one size larger than the engine size to compensate for non-linear loads.

The high volume of electrical equipment also creates electromagnetic interference. This is not the place to try to economize on construction costs. Electrical engineers often recommend rigid steel conduits for major feeders - especially those passing through critical areas - rather than the thinner, less expensive electrometallic tubing, which does not block magnetic interference.

The ratio of emergency to normal power is increasing. The trend is to place more systems on the emergency generator than dictated by minimum code requirements. For example, cooling is not required to be on generators, but more hospitals are electing to do so. Indeed, owners of facilities designed to meet code and budget requirements just a few years ago now may want to add systems to the emergency generator, only to find that their generators do not have adequate capacity.

Internet, Telemedicine Make the Call

The design of the telecommunications infrastructure in hospitals today is driven by the expanding need for high-speed, high-quality computing and networking both within the hospital facility and between the hospital and the outside world.

Hospitals already have in place or are adding new local area networks (LANs), often Ethernet systems, to network all types of data, from patient records to radiology data, throughout the facility. Now networks are expanding, with installation of data ports at each bed, allowing access to view and update patient records as well as diagnostic images. (The future is in wireless, portable access via hand-held computers, already being seen in some applications.)

Expanding the network to each bed necessitates upgrading the infrastructure to comply with the latest standards. This, in turn, requires telecommunications closets to be dispersed throughout the building, with certain distance limitations between the closets and each data outlet and certain closet size requirements based on the size of the area and the number of outlets.

Meeting these standards and future needs requires a lot of space and, when upgrading an existing facility or planning a new facility, owners and planners must be prepared to allocate it. Usually this space is in the core of the building, not in an underutilized corner, to meet distance requirements.

The good news is that current standards in the design of the telecommunications infrastructure should serve health care facilities well for 10 to 15 years.

This means that - even if new cable itself may be required in the next decade - the number and spacing of telecommunications closets should remain consistent - the crucial issue in space planning. Indeed, many believe that the next generation of cable will be "all we will ever need" in copper cable. Additional speed will have to be accommodated using fiber-optic cable.

The logical extension of the LAN is a wide-area network (WAN) that enables telemedicine: remote access to patient records, diagnostic images and other data by computer, with the capability of simultaneous videoconferencing. A lot of institutions are talking about telemedicine, and some are forming pilot projects. Some are making the connections between the hospital and physicians' offices and outpatient clinics over the Internet. Others are using dedicated T1 or ISDN phone lines, which offer higher-bandwidth (i.e., high quality) communication as well as quick speeds.

In fact, much of the capability for the WAN depends on the main telecommunications equipment in the building and the cabling that goes out to the world. Many hospitals have multiple T1 copper phone lines coming in and some fiber-optic cable. The trend is to bring in more fiber, which is what is really needed to drive video imaging. Either way, space is needed in the main telecommunications room for the large amount of equipment to communicate with remote sites.

Life Safety, Security

As it is in emergency power, so it is in life safety: The trend is to exceed code in both existing and new facilities. Many existing hospitals have outdated fire alarm systems and inadequate sprinkler systems by today's standards. Owners are retrofitting with modern, computer-controlled fire alarm systems - centrally monitored and controlled from a fire command station, usually in the main lobby.

The new systems require new water service, fire pump and vertical distribution system and additional sprinklers. This complicates the cost and space issues. A sophisticated mechanical system can also provide smoke control, either automatically or manually from the fire control station. This is a highly reliable early warning system.

Security systems are vendor-driven, changing rapidly, and are generally planned and implemented after a building is completed. Much of a security installation is low voltage. Thus, engineers should assure that enough space and power are allocated in the backbone for security hub equipment. Needs differ, but most security systems today use some combination of card access and biometrics readers, motion detection, closed-circuit television and metal detectors, as well as personnel.

Higher Demands

It's also worth mentioning that stand-alone ambulatory care facilities may place even higher demands on infrastructure because there is more sophisticated equipment packed into them than in some hospitals, which contain patient rooms and more support spaces.

Now, what about controls? Given the size and complexity of the hospital setting, integrated controls would seem to offer distinct benefits. Yet it is not only expensive but often difficult to build a system that integrates control of all mechanical and electrical systems because many control manufacturers' systems are proprietary.

There has been an effort in the market to develop "open protocol systems" - creating an integrated control system - but applications have involved links between components or subsystems rather than completely integrated automation systems. Today, it is more common to selectively marry major control components to the building management system regardless of whether the controls use open protocols. Continued introduction of products that use open protocols promises to expand the use of integrated control systems.

In the final analysis, designing a health care facility infrastructure for the 21st century is all about optimizing system integration and flexibility to ensure that the facility will remain a fully functioning organism in the future. Perhaps nowhere else is the metaphor of infrastructure as "backbone" more apt than in health care.

10 Questions To Ask Before You Choose A Roof

Choosing the correct replacement for an aged roof - or identifying the best choice for a new building - is no easy task. The perfect roofing solution for one building may be the worst option for another just down the street. That's because no two buildings are precisely alike, even if they closely resemble each other. So how do you choose a new roof, given all the choices in the marketplace? You can start by asking a series of questions, before you choose the roof, the roofing contractor or the manufacturer.

1. What is this building's mission statement?

Before calls are made to roofing contractors or manufacturers, the first item to address is the company's mission statement as it relates to the building.

Whether you are building new facilities or managing existing properties, you want to be confident that the roofing systems you select deliver the performance you expect. More often than not, the building itself dictates the appropriate roofing system specification.

You need to know as much about the building and its future as possible. Does the company plan to keep this building as part of its real estate assets for the next 10 to 20 years? Are there any plans to expand it in the near future, or to change its use? What are its current and future occupancy, insulation requirements, aesthetic priorities and even the maintenance schedules for rooftop equipment?

These and other mission statement issues will help shape answers to types of roofing to consider and how much of the capital budget is really needed for the job.

Start your questions with what is the building going to be used for. If it's a spec building, maybe you only need a basic roof. But, if the facility has a special use, such as an airline reservation center with computers in it, then your considerations for roofing options are quite different.

For example, as more companies move toward operating 24 hours daily, seven days a week to satisfy global customers, the data center must never spring a rooftop leak. Water on computer systems generally spells disaster.

A special set of concerns arise for cooling-dominated climates. Does the roof contribute to air conditioning savings and address other key issues? Is it part of a total energy program? There is a growing concern about urban heat islands. Reflective, white roofs have become of interest in those areas for a few reasons. They keep the building cooler, reduce air conditioning costs and also minimize the heat-loading of the surrounding environment.

2. What physical and other elements influence the roofing system selection?

After identifying the goals and mission of a facility, it's time to evaluate the building itself. You need to begin by looking at the building's location and the attributes of its surrounding area. You need to examine building codes, weather trends, topography - even the direction the building faces.

The physical characteristics of the building are also crucial: size, shape, design, height and age.


You also need to look at the construction materials used to build the facility and the location of HVAC and fire protection equipment, particularly if either or both of these are partially or totally housed on the rooftop.

When it comes to roof replacement, you need to list the attributes of the roof area itself. It's best to detail the roof's size, shape, slope, deck construction, edge detailing, protrusions, rooftop access and existing roofing system. Along with this basic information, you need to find out why the original roof is no longer adequate.

3. What flexible-membrane roofing options are available?

SPRI, the association that represents sheet membrane and component suppliers to the commercial roofing industry, identifies three major categories of membranes: thermosets, thermoplastics and modified bitumens.

Thermoset membranes are made from rubber polymers. The most common is EPDM, often referred to as "rubber roofing." These membranes are well suited to withstand the potentially damaging effects of sunlight and the common chemicals found on roofs. They are easily identified on the rooftop. Just look at the seams. Thermoset membranes require liquid or tape adhesives to form a watertight seal at the overlaps.

Thermoplastic membranes are based on plastic polymers. The most common is PVC, which is made flexible by adding plasticizers. Thermoplastic membranes have seams that are most commonly formed using heat welding. Most thermoplastic membranes are manufactured with a reinforcement layer, usually polyester or fiberglass to provide increased strength and dimensional stability.

Hypalon thermoplastic begins as a thermoplastic, but cures over time to become a thermoset. Like other thermoplastics, Hypalon materials are heat sealed at the seams.

Another thermoplastic hybrid is thermoplastic polyolefin (TPO), which combines the attributes of EPDM and PVC. TPO membranes do not cure after exposure to the elements and remain hot-air weldable throughout their service life. Most TPO membranes are reinforced with polyester, fiberglass or a combination of the two, but unreinforced TPO membranes are available.

Modified bitumen membranes incorporate the formulation and prefabrication advantages of flexible-membrane roofing with some of the traditional installation techniques used in built-up roofing. Modified bitumen sheets are factory-fabricated, composed of asphalt which is modified with a rubber or plastic polymer for increased flexibility, and combined with a reinforcement for added strength and stability.

4. Which type of membrane and attachment system are best for the building?

Many factors determine the best system for a particular building. For most buildings, there are a number of options and advantages that need to be weighed against the facility's mission statement. The decision should not be made only on the basis of cost. Other important considerations for membranes are building height, wind exposure, anticipated roof traffic and aesthetics.

The attachment system also depends on the specific building's characteristics. If the roof deck is able to withstand the weight, a ballasted roof may be the best option. But, if the slope of the roof is greater than 2 inches every foot, this system may not be appropriate. There are other limitations to ballasted systems, such as roof height, proximity to shorelines and other high wind zones, and the availability of ballast.

A steel or wood deck that easily accepts fasteners makes a good substrate for a mechanically fastened membrane. These systems can be designed to provide the necessary resistance to known wind forces and are not subject to slope limitations.

Another alternative is the fully adhered system, in which the membrane is attached to the prepared substrate using a specified adhesive. Depending on the membrane, the adhesive may be solvent- or water-based or asphalt. The finished surface of an adhered roof is smooth.

For those concerned with building aesthetics, colored membranes can make an attractive contribution to the building's appearance.

5. Does all roofing material delivered to the job site bear the UL label?

If not, specify that it must. This is the only way you can guarantee that the roofing materials installed on your roof are the same materials tested by Underwriter's Laboratories. Additionally, be sure that the roof assembly you buy or specify, which includes the insulation, is UL-classified and -labeled. Using an insulation other than what was tested with the roofing membrane may void the UL classification. If the UL Building Materials Directory does not list the roofing system you are sold, insist on verification of the classification in the form of a photocopy of the UL's letter of approval.

Make sure that the product you are getting is the actual product that was tested. You don't want something that is similar but not equal. Look for the label at the job site and make sure all components of the system were tested together. You want the membrane tested with the insulation that you are using on your building.

6. Does the system require a wind uplift rating?

Wind uplift damage can be extensive and expensive. Accepted as an industry standard, American Society of Civil Engineers Standard 7-95, "Minimum Design Loads for Buildings and Other Structures," can be used to determine the wind zone of the building. Wind uplift testing, such as that performed at Factory Mutual or Underwriters Laboratories, can be used to determine that the selected roof system meets or exceeds the local wind uplift requirements.

7. How much does the completed system add to the dead load weight of the roof structure?

In choosing any reroofing option, the facility executive should be aware of the load-bearing capacity of the roof deck to make sure the right flexible-membrane option is chosen. In new construction, savings in structural steel can often be achieved by installing one of the lighter flexible-membrane systems.

A ballasted thermoplastic or EPDM roof may require in excess of 1,000 pounds per 100 square feet, while a mechanically attached or fully adhered thermoset or thermoplastic membrane weighs 33 pounds per 100 square feet. A lighter system often allows you to reroof directly over your existing roof, while the heavier ones may require you to tear off the old roof and begin anew. But weight is only one consideration in the selection of a roof membrane and attachment system. A ballasted roof may be the best choice for a given facility. Facility executives must assure that all relevant considerations, including weight, are taken into account in the decision-making process.

8. What are the expertise and financial strengths of the roofing contractor you are considering?

Roofing contractors need to be chosen with great care. The introduction of new roofing materials and application techniques within the past 10 years has led to many changes. A professional roofing contractor should be familiar with different types of roofing systems, to help you make the best decision for your facility, based on your budget.

Ask the contractor if his or her company is a member of a local, state, regional or national industry association. Contractors involved in professional associations generally are better informed on the latest developments and issues of their industry.

Insist the contractor supply you with copies of insurance certificates that verify workers' compensation and general liability coverages. Check that those coverages are in effect for the duration of your roofing job. If the contractor is not properly insured, your company, as the property owner, may be liable for accidents occurring on the property. Also check your state's licensing requirements and find out if the contractor is bonded by a surety company.

The installation of different roofing systems varies considerably. Education and training are the most important elements in the installation of roofing systems. Make sure the roofing contractor you choose has had detailed and ongoing training on the system being installed.

One rule of thumb is to find out if the contractor has installed at least 100,000 square feet of the system you want in the past 18 months. Also, make sure the contractor is approved by the manufacturer to install that specific system.

The quality of workmanship is crucial to good roof performance. The National Roofing Contractors Association offers a professional roofing selection guide. In addition, many manufacturers have approved contractor programs with specific qualifications that roofers must complete before approval.

9. What is warranted and by whom?

There are two basic categories of roofing warranties. The contractor's warranty typically covers workmanship. The manufacturer's warranty covers at least the materials, though many cover additional items. Even if the manufacturer's warranty is broad, it will not completely protect you if the roof is improperly installed.

Carefully read and understand any roofing warranty offered and watch for provisions that would void it. For example, it's nearly impossible to avoid all ponded water. Ponded water can be caused by a clogged roof drain or deflection of the roof deck in between the support columns. Proper roof maintenance can help assure that the warranty remains valid. Be aware of warranty language that voids the guarantee.

Most professional roofing contractors will offer periodic maintenance inspections throughout the year. These inspections help ensure your project complies with the standards specified in the warranty. A typical maintenance program consists of a detailed visual examination of the roof system, flashing, insulation and related components to identify any potential trouble areas.

More important than the warranty, however, is getting the right flexible-membrane roof on your building in the first place. If the roof is correctly designed and installed to meet your facility's needs, building codes and geographical considerations, and the warranty covers those needs, you probably will be enjoying the benefits of a flexible-membrane roof many years after the original warranty expires.

10. After the roof is installed, what after service and educational programs are available for the facilities management team?

Seminars offered by roofing industry associations like SPRI and manufacturers can be invaluable ways for the building's roofing team to expand their understanding of commercial roofing system types, installation processes and maintenance considerations. Specific courses are available to help building owners and facilities managers learn more about various roofing systems, materials and components; insulation and accessory products; elements of roof design; contractor selection; warranties and maintenance considerations.

Energy Efficiency And HVAC Technology

The following overview offers a quick reference to key considerations with some of the most effective technologies. As with lighting, trial installations are a good idea; so is working with manufacturers and distributors.

Getting the most from HVAC controls

Because a building's performance can be dramatically improved by installing and fully using HVAC controls, it is essential to understand and correctly use those controls. The place to start is with a close look at what is really transpiring in your building, 24 hours a day, seven days a week.

What is happening with each piece of equipment? On holidays? Weekends? As the seasons change, do your operations change? It is important to understand where and how energy is being consumed in order to identify where waste is occurring and where improvements can be implemented. Then it is imperative to ask, "What exactly do I want these controls to do?"

Energy management systems (EMS) are designed to run individual pieces of equipment more efficiently and to permit integration of equipment, enhancing performance of the system. In a typical EMS, sensors monitor parameters such as air and water temperatures, pressures, humidity levels, flow rates, and power consumption. From those performance points, electrical and mechanical equipment run times and setpoints are controlled.

Seven-day scheduling provides hour-to-hour and day-to-day control of HVAC and lighting systems and can account for holidays and seasonal changes. As the name implies, night temperature setback allows for less cooling in summer and less heating in winter during unoccupied hours.

Optimal start/stop enables the entire system to look ahead several hours and, relative to current conditions, make decisions about how to proceed; this allows the system to ramp up slowly, avoiding morning demand spikes or unnecessary run times.

Peak electrical demand can be controlled by sequencing fans and pumps to start up one by one rather than all at once and by shutting off pieces of HVAC equipment for short periods (up to 30 minutes), which should only minimally affect space temperature. Economizers reduce cooling costs by taking advantage of cool outdoor air. Supply-air temperature-reset can prevent excessive reheat and help reduce chiller load.

An EMS can provide an abundance of information about building performance, but someone has to figure out what they want the EMS to do and then give it directions. Calibrating controls, testing and balancing are key to any well-maintained HVAC system, but are especially critical to optimize control efforts.

Variable speed drives and energy-efficient motors

Variable speed drives (VSDs) are nearly always recommended as a reliable and cost-effective upgrade.

VSDs are profitable where equipment is oversized or frequently operates at part-load conditions. Savings of up to 70 percent can be achieved by installing VSDs on fan motors operating at part-load conditions. They may be applied to compressor or pump motors and are generally used in variable air volume (VAV) systems. They are also cost effective in water-side applications. Backward-inclined and airfoiled fans are the best VSD candidates.

Air-handler configurations controlled by variable inlet vanes or outlet dampers squander energy at part-load conditions. Using throttle valves to reduce flow for smaller pumping loads is also inefficient. The efficiency of motors begins to drop off steeply when they run at less than 75 percent of full load; they can consume over twice as much power as the load requires. VSDs operate electronically and continually adjust motor speed to match load.

The power to run the VSD is proportional to the cube of the speed (or flow), which is why this technology is so efficient. If the speed is reduced by just 10 percent, a 27 percent drop in power consumption should result. A VSD pilot study performed by EPA found that VSD retrofits realized an annual average energy savings of 52 percent, an average demand savings of 27 percent and a 2.5-year simple payback.

Perform harmonic, power factor, electric load, and torsional analyses before selecting a VSD. Though harmonic and power factor problems are not common in VSD applications, VSDs should generally be equipped with integral harmonic filters (or a three-phase AC line reactor) and internal power factor correction capacitors (or a single capacitor on the VSDs' main power line). In general, this equipment is not standard and must be specified.

Improved design and better materials enhance the performance of energy-efficient motors, which use 3 to 8 percent less energy than standard motors; units with efficiencies of 95 percent are available.

To achieve maximum savings, the motor must also be properly matched with its load, increasing run time at peak efficiency. Motors operate best when running at 75 to 100 percent of their fully rated load; motors routinely operating below 60 percent of rated capacity are prime candidates for retrofit. For motors whose loads fluctuate, VSDs should also be considered.

Smaller, more efficient motors are integral to a system downsizing stratagem; downsizing a 75 horsepower standard motor to a 40 horsepower energy-efficient model will result in energy savings of 15 percent.

Some energy-efficient motors have less "slip" than standard-efficiency motors, causing energy-efficient motors to run at slightly higher speeds; consider a larger pulley to compensate for the higher speed and to maximize energy savings. Installing a new pulley or adjusting the existing one can also be an alternative to a VSD when the cost for the VSD is prohibitive or the load has been reduced.

Improving fan system performance

A common way to improve the efficiency of the air distribution system is to convert constant air volume (CAV) systems to VAV. One authority on energy issues, E-Source, reports that "typical (VAV) air flow requirements are only about 60 percent of full CAV flow."

VAVs respond to load requirements by varying the volume of the air through a combination of pressure controls and dampers rather than by varying the air's temperature. According to the air pressure, fan power and volume of conditioned air are reduced, thus increasing energy efficiency. Of course, it is crucial to maintain indoor air quality (IAQ) when altering air handling systems.

To maximize savings, VAV components such as VSDs, variable-pitch fan blades, diffusers, mixers, and VAV boxes must be operating properly; careful zoning is also required to achieve VAV optimization.

E-Source recommends considering the following VAV retrofit procedures:

• complete load reduction measures and calculate the maximum and minimum air flow requirements,


• measure existing fan performance; examine duct system for possible improvements,

• stage fans that are in parallel configurations,

• commission the system thoroughly,

• optimize static pressure setpoint and implement reset control, and

• possibly remove return air fans.

Energy-efficient and properly sized motors are also recommended along with careful control strategies. Installing a self-contained, thermally powered device to each diffuser can add greater control to VAV systems by controlling individual spaces, rather than entire zones, and eliminate the need for VAV boxes. Such a device also offers VAV-style capabilities to CAV systems.

VAV retrofit costs and paybacks can vary widely. Installation problems related to fan control, reduced supply air distribution, location of pressure sensors and their reliability, in addition to deficient design, can diminish a VAV retrofit's performance. Because VAV boxes are relatively expensive and one is required for each zone, it is generally not cost effective to partition the space into many zones. Careful zone designation -- according to occupancy, internal loads and solar gain -- will maximize efficiency, increase comfort and reduce reheat.

When reheat cannot be eliminated, consider these steps to minimize it: ensuring thermostat calibration; increasing supply air temperatures during the cooling season; and monitoring reheat year round and possibly employing reheat only during winter months. Where reheat is used primarily to control humidity, a desiccant wheel or a heat pipe might be considered.

Downsizing existing VAV fan systems is a relatively low-cost way to save energy when loads have been reduced or when the air distribution system was oversized to begin with. The following are means to downsize fans or airflow requirements:

• Reduce static pressure setpoint to meet actual temperature and airflow requirements.

• Rightsize motors and upgrade to energy-efficient models; install larger pulleys.


• Replace the existing fan pulley with a larger one; that will reduce the fan's power requirements by reducing its speed.

• Make sure the fan's speed corresponds to the load. Reducing a fan's speed by 20 percent reduces its energy consumption by approximately 50 percent.

There are several ways to determine if VAV fan systems are oversized. If a motor's measured amperage is 25 percent less than its nameplate rating, it is oversized. If a fan's inlet vanes or outlet dampers are closed more than 20 percent, it is oversized. If the static pressure reading is less than the static pressure setpoint when inlets or dampers are open and VAV boxes open 100 percent, as on a hot summer day, the system is oversized. Again, be sure to consider IAQ requirements when downsizing air handling systems.

Chillers and thermal storage

No one wants to replace a perfectly good chiller just because of the CFC phaseout. But once load-reducing efficiency upgrades have been completed, it may actually be profitable to replace an oversized chiller. That's especially true given rising prices and tightening supplies of CFC refrigerants.

Oversized units 10 years or older are good candidates for replacement. A high-efficiency chiller reduces energy costs throughout its lifetime; initial costs are reduced because the replacement chiller is smaller than the old one. Depending on the old unit's efficiency and load, a high-efficiency chiller's energy consumption can be.15 to.30 kW/ton less, decreasing energy consumption by as much as 85 percent if combined with downsizing.

An alternative to replacement is to retrofit chillers to accommodate a new refrigerant and to match reduced loads. That may involve orifice plate replacement, impeller replacement and possibly compressor replacement, depending on the chiller's specifics.

Retrofitting may entail gasket and seal replacement and motor rewinding. Depending on the refrigerant and the way the retrofit is performed, the chiller may lose either efficiency or capacity. To determine whether replacement or retrofit is a better option, consider both initial and life-cycle costs.

Retubing the condenser and evaporator yields sizable energy savings but whether it makes sense, given its high cost, depends on the condition of the chiller. Water-cooled condensers are generally more efficient than air-cooled units. Because condenser water flows through an open loop, it is susceptible to fouling. Scale build-up will inhibit heat transfer efficiency; maintenance is therefore required to keep the surfaces clean.

Absorption chillers are an alternative to centrifugal models. Absorption chillers cost up to $150 per ton more than vapor compression chillers like centrifugal units, but can be profitable in areas of high electrical demand charges or where steam or gas is available, depending on the local utility rate structures. Using a combination of the two chiller types can reduce electrical demand charges.

Thermal energy storage (TES) uses conventional chiller equipment to produce conditioned water or ice (or occasionally another phase-change material) in off-peak periods. Water is withdrawn from storage during the day or at peak hours and circulated through the cooling system.

TES systems can be incorporated into new and existing systems and can provide partial load leveling or full load shifting. TES helps decrease operating and maintenance costs; in some cases, a smaller chiller can be specified. Some systems provide lower supply air and water temperatures, so air and water flow requirements can be cut.

Water-side improvements

Fill material, size and fan configurations affect cooling tower efficiency. Cellular fill (aka film packing) increases efficiency over other fill types. Oversizing the tower to allow for closer approach to ambient wetbulb temperature can improve its efficiency. Generously sizing the tower and increasing its share of the chiller load can make economic sense because a cooling tower's initial cost and energy use per ton are less than a chiller's.

At part-load conditions, applying a VSD to the fan (or pump) will improve the tower's efficiency. Systems with VSDs and several fans are more efficient when all tower cells are operating at reduced speed as opposed to one or two cells at full speed.

Because cooling towers contain large heat exchange surfaces, fouling -- scale or slime build-up -- can be a problem. The efficiency of improperly treated systems can be improved with effective water treatment. High-efficiency towers are available; induced-draft types are more popular and efficient than forced-draft towers. Performance can also be improved by increasing cooling surface area.

In traditional pumping systems, flow is generally constant volume; a throttle valve reduces flow at part-load conditions, inhibiting efficiency.

Installing VSDs on secondary pumps in variable flow systems, rightsizing pumps and motors to meet load requirements, and upgrading single loop systems to primary/secondary loop configurations can increase the performance and reliability of pumping systems. In upgrading chilled water pumps, it is important to meet maximum and minimum flow rates through the chiller.

Other cooling options

Desiccants are dehumidification materials which can be integrated into HVAC systems to reduce cooling loads and increase chiller efficiency while improving indoor air quality and comfort. Formerly found only in niche and industrial applications, desiccant cooling is extending throughout commercial markets.

Desiccants make sense when the cost to regenerate them is low compared to the cost to dehumidify below dewpoint and can reduce HVAC energy and peak demand by more than 50 percent in some cases.

Evaporative coolers provide one of the most economical and efficient means of cooling, using up to 75 percent less energy than vapor-compression systems. Though initial cost is typically higher, paybacks for evaporative coolers range between six months and five years. Though evaporative coolers are particularly prevalent in the arid West and Southwest, they can service most U.S. climates. E-Source states that, in combination with evaporative cooling, desiccant cooling can eliminate refrigerative air conditioning in many climates.

Hybrid systems that integrate evaporative cooling with conventional HVAC technologies offer additional opportunities. To improve performance consider lower air velocity; better fill materials; higher fan, pump and motor efficiencies, including VSDs; better belts or direct drive; improved housing; improved controls; and duct sealing. Proper maintenance is key to energy-efficiency.

Packaged air-conditioning units are typically found in buildings or building zones where the cooling load is less than 75 tons. Running these units at part load can severely reduce efficiency. They are generally not as efficient as chiller systems but can be upgraded and rightsized when replaced. Existing systems can be improved by using higher efficiency compressors, larger condensers and evaporators, and VSDs, though life expectancies of 10 to 12 years for these technologies may mean that retrofits are not cost-effective.

Heat pumps are among the most energy-efficient heating and cooling technologies available today. Low operating costs, increased reliability and long life expectancies improve their viability. They function best in moderate climates and proper sizing is critical.

Multi-unit configurations can service larger loads and provide zoning; large, modernized central units offering capacities of up to 1000 horsepower or 750 kilowatts are gaining popularity. Air-to-air type heat pumps are the most common because of low up-front costs; ground supply heat pumps are the most efficient but tend to have higher initial costs.

Boiler upgrades

Especially in colder climates, improved boiler performance -- with improved fuel and airflow controls over a range of load conditions and increased heat transfer surface areas -- can contribute substantially to energy savings. Smaller units arranged in modular systems increase efficiency up to 85 percent while small units replacing those with open-loop condensing systems shoot combustion efficiency up to 95 percent.

Boiler retrofits, combined with improved maintenance measures, can also increase efficiency -- up to 90 percent. New burners, baffle inserts, combustion controls, warm-weather controls, economizers, blowdown heat recovery and condensate return conversions provide increased efficiency opportunities. A smaller "summer" boiler might be a good option when a boiler is required year round though at reduced capacities in warmer conditions. The much smaller summer boiler is sized for reduced loads; the main boiler is shut down.

HVAC upgrades can provide tremendous economic benefits, improve occupant comfort and system reliability, and reduce operating costs. But to maximize benefits and minimize capital investment, load-reducing measures, such as lighting upgrades, should precede HVAC system upgrades.