We've retired to the North Carolina coast and plan to build an energy-efficient home there. We're receptive to just about any type of structure but do want something that'll offer significant energy savings in relation to our initial investment. Is a super insulated house actually cost-effective in the climates typical of the Southeast?
Definitely. A super-insulated home can be cost-effective on the cold plains of central Minnesota, in the moderate mountain climate of western North Carolina, or in the warm ocean climate of Cape Hatteras. Essentially because it can contain, as well as keep out, both cold and heat, much as does a vacuum bottle.
I've put together a Super Insulated Home Chart to clarify the advantages.
Table 1 briefly summarizes the construction and insulation differences between a conventional and a super insulated house, though the recommended insulation levels would depend on the regional costs of labor and materials, as well as on the climate.
Table 2 shows heating and cooling savings for a typical super insulated home (if the design, construction costs, and materials costs are the same for each example) in the locations I've mentioned.
In a nutshell, winter heating needs can be reduced in a super insulated structure by more than 80 percent in Minnesota, and by 94 percent to 97 percent in the North Carolina locations. The same dwelling designed for the Minnesota climate can cut air-conditioning needs by 60 percent.
Michael Scott is an insulation expert and super insulation pioneer.