By Katherine Salant
You want your new house to be energy efficient with good indoor air quality, but how much can one conscientious buyer do? Quite a bit according to homebuilder David Johnston, of What's Working, an environmental consulting firm in Boulder, Colorado.
You won't have to start at ground zero because all homebuilders today are concerned with energy efficiency and indoor air quality. But you can significantly increase these over the norm offered in your market if you select a builder who is willing to change a few items on his standard specification list, Johnston said. The substitutions that he recommended would not require the builder to alter his standard procedures, and they are readily available. Of course, he added, you must be willing to cover the added cost, if any.
Before you even begin to discuss changes in the house itself, you will go a long way towards making your house more energy efficient just by choosing a lot in which the major living spaces face south. In the winter when the sun is lower is the sky, its warmth which is freewill help heat up the space during the day, and south light can "help to chase those winter blues away" because it penetrates farther into the living space, bathing more area in natural light. Adding a roof overhang insures that during the summer when the sun is high in the sky, these south-facing areas are shaded during the hottest times of the day. Summing it up, Johnston said, "In terms of lifestyle, energy and aesthetics a southern orientation is a win-win. I have lived with south-facing houses for more than twenty years and I can't imagine ever living with anything else." That's saying a lot, given the breathtaking views of the Rockies to be had in west-facing houses in Boulder where he lives.
Focusing on the house itself, Johnston said the first thing to discuss with a builder is upgrading the windows. He may already use windows with two pieces of glass, but adding a low emissitivity (commonly called low e) coating to the inside surface of one of the sheets of glass reduces heat loss and heat gain through the windows even further. Virtually every window manufacturer in the country now offers this option, so it would not be hard for your builder to get it. If your builder uses windows with aluminum frames, the low e will help, but you should try to substitute these for ones with frames made of vinyl or wood because aluminum is an excellent conductor, and it will channel heat straight into the great outdoors in the winter. In warmer areas, an aluminum frame is acceptable, though not optimal, if the frame has a thermal break.
The next place that Johnston would look is the roof and attic space below. Unbeknownst to most home owners, the temperature of attic spaces in all climate zones in the US during the hot summer months can be as high as 140 degrees F., even when the outside air temperature is much lower. The heat buildup in the attic cavity constitutes a major portion of the air conditioning load for the entire house, so anything that you can do to reduce it will increase energy efficiency as well as lower your electric bills.
If your builder offers you some choice in the color of the roof shingles, choose ones that are light colored, Johnston suggested. These will absorb less heat from the sun, which in turn will cause less heat to build up in the attic space below the roof. Increasing the attic insulation three to six inches will slow the rate at which the heat will pass through the ceiling to the living spaces below the attic. If you live in a climate that is warm most of the year such as Florida or Southern California, you can reduce the heat buildup in the attic even further by adding a radiant barrier. This may sound exotic, but it amounts to getting standard 4 by 8-foot sized sheets of roof sheathing with aluminum foil laminated to one side, and these are widely available.
Inside the house Johnston recommended appliances that carry the Energy Star designation, which means that the appliance exceeds the federal standards for energy efficiency for that particular appliance. Energy Star rating systems have been established for refrigerators, dishwashers, and washing machines as well as for entertainment devices such as televisions and VCR's and home office equipment including computers, printers and fax machines (for more information, see the Energy Star website, www.energystar.gov).
Another criterion for choosing appliances is water usage. Characterizing water as the "black gold of the 21 st century," Johnston noted that most dishwashers except very low-end models have a water saving feature. While both top and front-loading washing machines carry the Energy Star designation, a front-loading washing machine uses about one-third less water than a top loader, less energy is required to operate it, and it gets more water out during its spin cycle so less energy is needed to dry the clothes.
For the bathrooms in your new house, look for fixtures that use less water. For the master bath, Johnston recommended a tub with a standard width but one foot longer"it's more convenient for a taller person and it doesn't use nearly as much water as a trendy soaking tub." You won't have much choice about the toilets, as all builders must use the federally-mandated 1.6-gallon type. But, Johnston said, most of the water-conserving toilets manufactured now are much improved over the first ones, which made most consumers mad because "they didn't work well and you had to flush twice."
Johnston also suggested making some product substitutions to improve the indoor air quality of your new house. Concerted efforts to make houses more energy efficient have made houses more airtight. And this, in turn, has exposed occupants to greater concentrations of volatile organic compounds generally referred to as VOC'sthat off-gas from many building materials. To reduce your exposure, Johnston would use low or no VOC paints, which are widely available as nearly every paint manufacturer makes them now. He would also use solvent-free adhesives for gluing down subflooring (many builders "glue and screw" this), ceramic tile, sheet vinyl, and trim around doors, windows and wall bases. And he would use an oriented strand board commonly called OSBmade with an MDI-resin instead of a formaldehyde based resin.
If your builder is willing to entertain a substitution that would require him to do things a little differently, Johnston suggested using mastic, a gray or white paste, to seal the air ducts instead of tape which will fall off in a few years' time. Once the seal breaks and the ducts begin to leak, as much as twenty five percent of the energy used to heat and cool your house will be lost.
Copyright 2001-2006 Katherine Salant. Distributed by Inman News Features
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