Within five minutes, the temperature shot up to 1,000 degrees Fahrenheit, then 1,750 degrees after 60 minutes. If the wall had been wood, it would have burned. After one hour, the temperature on the cool side had actually dropped two degrees, according to Perry, because a fan had been blowing. Remember, it could heat up to 250 degrees before failing the test. For the wind test, the equivalent of a 75 mph gale was directed at the wall.
Higher numbers indicate relatively better insulation.
A six-inch wooden wall with fiberglass insulation, for example, carries an R factor of 19. The average roof rates R30. One bale of straw without any plastering rated R48. We've taken a very thorough, professional approach to this and had all the tests done by outside professionals. Everything was done according to acceptable standards, which is why the state has moved forward.