People have known for thousands of years that sheep’s wool has excellent insulation qualities. We’ve been making garments out of wool for centuries, so it is surprising that it’s taken this long for wool to be considered a viable insulation for buildings. Thermafleece is a patented sheep’s wool insulation material for buildings, produced by Second Nature in northern England. Unfortunately for Americans, Sheep’s wool doesn’t seem to be too easy to come by in the US at this moment. Fortunately for us, we can stick with the all-American blue jean insulation
ICYNENE
There are a several varieties of spray-in foam. They start out in liquid form, and expand and solidify almost instantaneously to fill minute cracks and crevices. These high-tech foams are more flexible than the “Great Stuff” you’ve seen at Home Depot, and also allow trapped moisture to evaporate. Not all of these products are the same, though. Some of these formulas are chemical minefields, while others such as Icynene, are water blown and produce no off-gasses whatsoever. Additionally, these usually cost three to four times more than traditional fiberglass and must be done by professionals.
NANOGEL / AEROGEL / KALWALL
Aerogel is a super-futuristic form of “frozen silica smoke” - made of a special type of super-porous silicon foam that is 99% air. It’s incredibly strong, incredibly insulating and incredibly light. Aerogels have extremely small pores, which makes them one the best thermal insulators in the world. Nanogel® is Cabot Corporation’s trademark name for its family of translucent silica aerogels. The great thing about Nanogel is that it is light and transparent, while being extremely insulating - so you can use it to create insulating windows and skylights, as well as translucent walls and ceilings that will let the light in, but keep the heat out.
