I have a question about insulating the attic space in an addition
bruceboy
| Posted in Building Code Questions on
I am planning a 360 square foot addition with a 12 x 12 gable roof so there will be a large attic space. The ceiling will be 2 x 12 joists to allow for a clear space in the room below. I will put r-38 fiberglas between the ceiling joists to meet code. My question is if I later choose to insulate the roof rafters later on can I leave the insulation in the ceiling?
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Replies
Bruce,
Q. "If I choose to insulate the roof rafters later on, can I leave the insulation in the ceiling [attic floor]?"
A. Yes. But if you plan to convert your attic to living space, you should realize that building codes require that the insulation that you install along the sloped roof plane must meet minimum code requirements -- which in your case evidently means R-38. You won't be able to count the insulation between the floor joists as providing partial insulation toward your minimum code requirements when you encapsulate the attic.