This is an essay that I wrote in 1992.

"SUPER - INSULATION"

By: Greg Roberts

"Super - Insulation " is a general term that is used to describe advanced construction techniques relating specifically to energy efficiency and "Building Science". No one knows when the term, or the idea of building science began, but more than likely it started during the 70's energy crisis and the resulting push for energy efficiency in new homes. There is no real definition of what a super-insulated home is. The term has been used to describe many different building techniques over the years. One constant, however, is that super-insulated homes seem to always be at the forefront of technology, new ideas, and new products used to enhance the efficiency, livability, comfort, quality, and health of new homes.

The house building industry has always been a slow but ever changing one. New home construction methods have changed over the years for many reasons. The push for energy efficiency in the last two decades has perhaps created the most sweeping changes we've seen in new home construction in at least the last century. The desire for more insulation, and the resulting air-tightness of new homes has had an immediate and significant impact on the methods we use in all phases of construction. It has actually caused the need to think about the home as a system, rather than a hap-hazard collection of building techniques.

House owners were generally spared air quality or moisture problems until homes began to be insulated and air tightened. Seventy-five years ago, homes didn't suffer from poor air quality. Problems with moisture, in the form of a vapor, condensing on windows, or more seriously, moving into a wall cavity and causing rot, were unheard of. One could argue that the reason a two-hundred-year-old house is still standing today is because it stood for one-hundred and fifty years without any insulation or barriers. When old farmhouses had holes big enough to throw a cat through, owners weren't concerned about adequate air change inside the home. With a cheap and abundant supply of fossil fuels to burn to heat homes, the need to lower heating costs wasn't a pressing issue either. My, how things have changed over the last few decades. Now you wouldn't think of building a home without insulation, and you shouldn't think about building one without ventilation. There are vapor barriers to worry about, or is that air/vapor barriers? There are dew points to consider, air change rates, infiltration, exfiltration, static pressure, moisture mitigation, roof ventilation, ice dam protection, and on and on and on... You begin to see why the term "Building Science" came about. It became a science as the industry defined problems, provided answers, and applied new techniques to improve new home construction. This is what building science is about. It is what a properly built super-insulated home is about. So it is possible to say that super-insulation, by definition, is really the proper application of building science.

It is impossible to set standard guidelines defining specifically what super-insulation is. There are simply too many variables in climate, builders, product availability, etc... I can only state what I believe are basic guidelines for building a super-insulated home in the state of Maine.

Wall insulation of at least R-35 and slant roofs or ceiling insulation of at least R-60.

Complete insulation on the entire foundation, including isolation of all concrete so that there is no concrete to ground contact.

Complete waterproof membrane under and around all parts of the foundation to eliminate any moisture, in any form, from entering the home.

Adequate construction techniques to completely prevent air or soil gases from moving in or out of the foundation area.

Adequate roof and attic ventilation.

Adequate construction techniques to stop bulk air movement through the exterior sheathing and into the wall cavity, or from soffit areas into insulated walls or ceilings.

Adequate construction techniques or barriers to stop bulk moisture (water leakage) from entering the walls or ceilings.

Complete air/vapor barrier on the inside (warm side) of the insulation on all exterior insulated walls and ceilings of the home.

Detailed air-tightening of the air/vapor barrier around any and all protrusions, between floors around the floor joists, behind the intersection of an interior wall to an exterior wall, and between different sections of the house, to completely stop air or moisture from moving into the walls and ceilings.

An adequate interior ventilation system in the home as part of the original construction plans and specifications.

Pin point possible sources of air quality or moisture problems, and seek ways to fix them before you build your home.

Consider minimizing the use of upholstered furniture, carpeting, or any other potentially unhealthy furnishing inside your home.

Always design the garage as a separate building from the main house, and don't use space above the garage as living space.

Consider isolating the mechanical system, laundry, and heated storage away from the main living area of the house.

Always use high efficiency, sealed combustion, direct venting heating appliances.

Test homes for air leakage.

This is by no means a complete list, nor is it very detailed, but it does shed some light on the relatively recent changes we're seeing in new home construction today. It also shows the need to think about your new home as a system. If these ideas seem new to you, I'm not surprised. Our industry is very slow to change, which I suppose is good in some respects, bad in others. One thing is for sure, though, building a super-insulated home today, using the proper techniques, will provide a trouble-free, energy efficient, comfortable, long-lasting, and healthy home for any family; and I'd take that over any other older system of construction any day.