AFCEE environmental experts walk the talk

  • Published
  • By Jennifer Schneider
  • AFCEE Public Affairs
LACKLAND AIR FORCE BASE, Texas --  Some environmental experts at the Air Force Center for Engineering and the Environment here have taken their mission to 'green' the Air Force a step further and incorporated several environmentally friendly features when constructing or remodeling their own homes.

The scoring system used to assess sustainability across commercial building designs, the U.S. Green Building Council's Leadership in Energy and Environmental Design system, is familiar to many of those involved in AFCEE's military construction mission.

As of 2008, a LEED rating system was made available for residential homes as well.

The rigorous process toward LEED certification analyzes several home components and awards points in such areas as water efficiency, use of environmentally preferable materials, landscaping features, indoor environmental quality and energy and atmosphere.

When designing and constructing an energy-efficient home, the U.S. Department of Energy recommends a "whole-house systems approach" which considers the interaction between the building site, the climate and several other home elements. This approach recognizes that the features of one component in the house can greatly affect other components, thereby affecting the overall energy efficiency of the home.

Erica Becvar, AFCEE's environmental management system program manager, said that while she didn't seek a formal LEED certification when undertaking a remodel of her 1937 cottage in Alamo Heights, she was determined to incorporate many of green principles touted by the USGBC and the DOE.

"While we knew we didn't have the time, nor was our contractor LEED-certified, we did know that we wanted to reduce, reuse and conserve where possible," Becvar said. "I had taken LEED training and was thus aware of LEED principles and what could be done on a residential structure. I also have good friends at AFCEE who are very passionate about their environmental professions and have shared their knowledge and interest in ways to reduce, reuse and conserve in building and remodeling."

Some of the energy-efficient aspects she incorporated in the remodel included the use of a non-volatile organic compound, or VOC, spray foam in the 230-square-foot home addition as well as in existing walls and under the home to help insulate the structure.

She replaced the existing asphalt roof with a metal roof and also installed energy-efficient windows and a new efficient heating, ventilation and air conditioning, or HVAC, system.

Becvar also took into account the home's location on the lot, minimizing windows on the west-facing wall of the home to reduce heat gain and adding large, high windows to the north-facing side to allow light to penetrate farther into the home and reduce the need for artificial lighting. She also installed a solar tube in the bathroom to make further use of natural lighting.

Efforts were made to improve water efficiency in the home by installing new low-flow plumbing fixtures and installing a hybrid water heater system. Hybrid water heaters combine the technology of tank and tankless conventional hot water heaters, by using a multi-pass design to increase efficiency in addition to including a small storage tank to provide higher capacity. She also added five rain barrels to the property along with the infrastructure needed to collect condensation from the air conditioning unit and roof and divert it to the barrels.

The environmentally friendly practice of material reuse was also implemented, as Becvar reused old kitchen cabinets and countertops in the new laundry room and reused and incorporated flagstone, siding and a front door from other remodels in her home.
Becvar said she has been pleased with the results.

"My profession is environmental, and I am the EMS AFCEE program manager, where you consider the impact on the environment in all activities you do," she said. "As an additional benefit, my electricity bills have stayed the same or been reduced, even though we added to the size of the home."

Becvar's coworker, Nancy Carper, AFCEE subject matter expert for integrated solid waste management, shared the same concern for the environment when constructing her new home.

Some of the features Carper included to improve energy efficiency were tankless water heaters, high-efficiency windows, programmable thermostats, a radiant barrier on the exterior of the home and spray-foam insulation throughout the structure.

In line with her occupation, diverting waste from the landfill was an important consideration. To avoid future land-filling of roof shingles, a standing-seam metal roof was installed. Carper also made use of old cedar fence boards, which resembled weathered barn wood, as an interior finish in the kitchen and dining areas.

Landfill diversion was also a consideration when clearing brush and trees from the home site. A large cedar tree, which had been growing in the proposed home site, was utilized as the home's fireplace mantle. To divert other wood debris from the landfill, the contractor hired a wood grinder to come to the construction site, leaving the ground wood onsite for landscaping purposes. Other trees and shrubs from site clearing were sent to a local composter, with the compost being applied prior to sodding the yards in an effort to increase water retention and root stabilization. The yards were landscaped with native plants and trees.

Another feature Carper installed was an aerobic septic system, which pumps gray water from the system to an irrigation system on the property, instead of releasing the water via underground leach fields.

Carper said the energy savings have been significant.

"Electricity consumption is much lower, just about cut in half, with this house yet the square footage is larger than the house we previously owned and lived in," Carper said. "Even though the costs to put most of these items into our construction were more expensive than longstanding, conventional construction materials, we were willing to put in that extra money upfront to reap the long-term savings."