In the last article, we reviewed why the LEED (Leadership in Energy and Environmental Design) process is important to hvac/mechanical contractors, provided a quick overview of the commissioning process, and briefly discussed how commissioning could prove to be a profitable service for hvac/mechanical contractors to offer. (Architects and engineers already offer LEED commissioning, which our customers want to ensure buildings are not making occupants sick or uncomfortable, which hinders job performance. Customers also want energy efficiency and environmental responsibility from building-related service providers.) Hopefully, some of you have started to investigate commissioning and are figuring out how best to integrate it into your current business.

Let’s continue looking at the LEED process and the areas where hvac/mechanical contractors can create value for their customers and communities and profit for themselves. Within the Energy and Atmosphere category of the LEED rating system, there are two other prerequisites beyond commissioning. These are refrigerant management and minimum energy performance. The LEED rating system gives “points” for performance in these areas.

Refrigerant Management

For new buildings, LEED processes require zero use of CFC-based refrigerants. This means hvac equipment using HCFC-22 (R-22, Freon) cannot be used. In existing buildings, contractors must have a plan for phasing out CFC usage in the building prior to completion of the project. Fortunately, most of the major hvac equipment manufacturers now sell equipment that does not use CFC-based refrigerants, so it’s not difficult to meet this requirement.

For packaged equipment up to 20 tons, most manufacturers use R-410a as the refrigerant. R-410a is a chlorine-free refrigerant with an ozone-depletion potential of zero. However, it does have a global-warming contribution of 1,890. Other non-CFC based refrigerants (used in packaged rooftop units, water-source heat pumps, water- and air-cooled chillers, and split systems) are R-134a, R-407c, and R-417a. The Montreal Protocol places no restrictions on the use of any of these refrigerants.

Because R-22 (HCFC-22) can still be used under the Montreal Protocol, the majority of packaged equipment still is being produced using R-22. However, as I mentioned above, if packaged equipment is being considered for a building, it is possible to obtain products that do not use CFC-based refrigerants. These products cost slightly more; however, they typically are more efficient than their R-22 counterparts and have reasonable payback time periods.

Energy Performance

The largest number of points available within the LEED rating system typically is obtained from the Optimized Energy Performance area. Up to 10 points can be earned based on energy reduction as compared with a baseline building as described in ASHRAE 90.1 Appendix G. (This must include all energy used within the building.)

Developing this analysis can be time consuming, and a licensed professional usually performs it using a variety of energy-analysis programs. DOE 2, BLAST, Trane Trace, Carrier Hourly Analysis Program, or other energy-modeling software can be used, provided it is capable of producing an hour-by-hour analysis for the 8,760 hours available to the building for a single year.

You should become familiar with at least one of these modeling tools. Many professional engineers, just like contractors, have taken to using “rules of thumb” when determining heat loss and gains for a building, simply because it’s the fastest, easiest way to get the job done. But by actually calculating heat losses and gains, we often can show owners how to reduce costs by using different equipment and associated distribution systems, which often do not need to be as large as designed.

For buildings 20,000 square feet and smaller with a primary occupancy of “office,” LEED provides a way to receive four points. To obtain these points, we must comply with the measures outlined by the ASHRAE Advanced Energy Design Guide for Small Buildings – 2004. For many hvac/mechanical contractors, such buildings are the bread-and-butter of our businesses because we maintain and build them. Become familiar with this guide, and then educate your customers on the benefits of implementing the strategies it recommends. We can help lower customers’ operating expenses and improve their indoor environments by implementing these strategies.

More points are available and can represent potential revenue and profit opportunity for hvac/mechanical contractors under the Indoor Environmental Quality section.

Air quality: One point is available for monitoring the level of outdoor air delivered to the building. Another point is available if breathing-zone outdoor-air ventilation rates are 30% or more than recommended by ASHRAE 62. This is challenging because we need to determine the impact on the energy used within the building as we increase the ventilation rates. Obtaining this point could result in lower energy reduction than we might have anticipated.

Developing and implementing during-construction and pre-occupancy Indoor Air Quality (IAQ) management plans can earn an additional two points. These plans can provide a methodology for “flushing” the building prior to occupancy, which will be good for the future occupants as the level of volatile organic compounds (VOCs) can be reduced substantially.

Controllability: By increasing the controllability of the system (provide individual comfort controls for 50% or greater of the occupants), one point can be obtained. Hopefully, if we did our job correctly, and developed heat-loss and -gain calculations for the buildings, we used ASHRAE 55 guidelines for thermal comfort. By demonstrating that we followed ASHRAE 55, an additional point can be obtained. There are other points available within this area, but perhaps the one I like the best is a result of monitoring the thermal comfort of the occupants.

Thermal comfort: A point can be earned for monitoring the thermal comfort of the occupants for six to 18 months after formal occupancy of the building has taken place. This is accomplished by performing a survey of the occupants. If more than 20% of the respondents are dissatisfied, then an action plan must be developed and implemented to correct the discomfort. This survey also provides a good marketing tool: What better way to brag about our hvac systems than to be able to say we made people comfortable, and we know it because we asked!

We’ve covered a lot of ground in two short articles. I hope you’ve found them to be useful and will begin to explore the LEED process and how you, as a professional hvac/mechanical contractor, can use it to improve your business and make our world a better place for our families, friends, and future generations.

What is LEED?

The Leadership in Energy and Environmental Design (LEED) Green Building Rating System is the nationally accepted benchmark for the design, construction, and operation of high-performance green buildings. LEED promotes a whole building approach to sustainability by recognizing performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection, and indoor environmental quality.Source: U.S. Green Building Council, www.usgbc.org

Ellis G. Guiles Jr.’s certifications include P.E. MBA, HERS Rater, and BPI Certified Professional (building analysis, envelope, heating, A/C and heat pump).