How to Build an Energy-Efficient Home

Next to moving day, nothing matches the excitement of sitting down with a floor plan and seeing your new home for the first time, if only on paper or the computer. Of course, not everyone has the luxury of designing a home from scratch. But that's no reason to ignore a frequently overlooked consideration in building design--energy efficiency. While you're deciding whether to open your wallet for the builder's laundry list of amenities and luxury options, why not make your home more comfortable, healthy and energy efficient, and increase its resale value down the road?

Naturally, you're usually working from the builder's plan, and there's always cost and other constraints faced by builders and their subcontractors. The good news is, energy efficient designs need not be expensive to construct. Every homebuyer stands to benefit from recent technological improvements in building elements and construction techniques, and heating, ventilation, and cooling systems, all of which can be seamlessly integrated into any type of house design.

The added benefits are not what you might expect. It's not just lower heating and cooling bills that come from lower fuel consumption. In addition to hundreds of dollars in potential energy savings each year, houses with better insulation and tighter construction tend to be quieter. Less noise is transmitted from room to room, or from outside sources. Plus, indoor humidity is better controlled, and bone-chilling drafts in the winter are reduced.

The first aspect of energy efficient design is constructing the "thermal envelope," the building components that physically separate the living spaces from the outdoors. Wall and roof assemblies go beyond the traditional "stick" (wood stud), framed wall type of construction. For example, Structural Insulated Panels (SIPs) are plywood or oriented strand board sheets laminated to a core of foamboard. Since the SIP acts as both the framing and the insulation, construction is much faster. The quality of construction is often superior because the units are prefabricated under factory-controlled conditions.

Remember also to demand more insulation than the bare minimum that local building codes require, depending on local climate. R-11 in the exterior walls and R-19 in the ceiling just don't cut it in colder regions, go for R-20 to R-30 in the walls, and R-50 to R-70 in the ceiling. Moisture build-up is always a consideration. Talk to your builder about methods of controlling air and water vapor movement. Otherwise, any water vapor that does manage to get into the walls or attics must be allowed to get out again, or it could damage the structure.

Of course, heating, cooling, and ventilation systems must all work together. Tightly sealed homes should be ventilated to reduce air moisture infiltration, prevent mold and get rid of dangerous indoor air pollutants. But energy efficient homes require relatively smaller heating systems. And although building your home may require a little more time and money, it just means research and budgeting, done together with your builder, to arrive at the best balance of cost vs. benefits.

Sources used to create this article include U.S. Department of Energy.