Best roofing insulation to keep warm in the winter?
depending on where you live,if possible,r30 fiberglass or blown in either is the standard around here,and,for sure never block your ventilation,you need the air in your attic,freezing cold attics don't make you cold if you're properly insulated
You mean the insulation that you put in your attic or crawlspace? That fiberglass stuff works pretty good- just roll it on out- the thicker it is the higher the R factor. Just remember to not reduce the air circulation especially around eaves, or you'll get condensation.
The best insulation that you will find is R15 fiberglass that is installed inside the attic between the roofing rafters. It's twice as thick as R12 which goes behind wall paneling. If you're talking about roofing shingles, they don't really act as insulation but architect shingles last the longest.
I have never heard of aluminum insulation and I don;t think it would work very well. Hot and cold flow along metal very quickly. Up here in Canada our code calls for R40 minimum. That's 12 inches of insulation. You can use 2 R20's and get the same. The R15 the guy spoke of above this is not twice as thinck as R12. R20 is almost twice as thick. Blown in is the best specially after all the work is done. If you try and put batts up there after it's a pain in you youknowwhat.
Aluminum is a good resister to thermal flow, but its primary characteristic is to stop the transfer of air. A solid barrier of aluminum will stop air movement, and will reflect heat back. A drawback is that it must be installed in a way so that no air can move through any cracks. Blown in fiberglass is your best bet. Trapped air is what insulates a space. Cellulose settles with gravity after a period of time, the fiberglass does not settle, traps more air, and can have a resistance value of up to 33. A well-insulated attic will keep you warm in winter, and keep the hot attic air from infiltrating your home in summer.
