Almost any exisiting structure whether commercial or residential can benefit from a green retrofit. A green retrofit means increase property value, quicker sales and happier occupants. It also means lower energy bills.
Of all the projects you can undertake in a green retrofit, the number one in terms of return on investment has to be insulation. Some would say it's the number two and three as well.
When it comes to insulation you need to know the term R-Value. If you don't already know it R-value measures the material's resistance to heat transfer. The higher the number the slower heat will pass from one side to the other. But, like so many things, it's just not that simple in real life. R19 insulation may seem better than R13 insulation in the laboratory or on paper, but I've known plenty of R13 walls that perform 2 to 3 times better than another R19 wall.
The most effective form of insulation when it comes to energy efficiency is spray-on polyurethane foam - or just "spray foam". And the most established and well known brand in that area is Icynene. Compared to typical fiberglass batts, Icynene spray foam is far more effective because it seals the space tight. Fiberglass is not an air barrier. Look at old batts in an older house and you'll see darkening and discoloration from the air it has "filtered" leaking into the house. I recently pulled some off the underside of my floors and it was black around the air ducts. Ick! Stop the air leaks and you save energy. But you do need to balance that with supplying clean fresh air in the right amount (7.5 cubic feet per minute per occupant is usually enough) to the house.
Typically older homes will opt to spray the attic and if they have one, the crawlspace. On a retrofit basis Icycnene spray foam can cut electricity bills around 30-40 percent.
This is quite an interesting posting on spray foam insulation for retrofits. I am sure many out there would find this article helpful.
Posted by: NYC AC Units | Aug 10, 2010 at 03:13 AM