i live in new england. my biggest question is not whether or not to use a radiant barrier, but how much insulation works best with it? The house i just moved to has very little insulation in the attic. Should i beef up the insulation first or only add the radiant barrier?
Linda, there isn’t really a way to do it without pulling down the sheetrock and emptying out the cavities OR without losing ceiling height. The foil HAS to have an air gap in order to work, so you have to create that gap either in the cavity or on the ceiling, which decreases the height in the room.
Good evening. Thank you for sharing your knowledge. I live outside of Houston so it’s very hot and humid for the majority of the year. I want to insulate an open frame (2×4) shed that has a gambrel style roof. I want to use a radiant barrier (after an air gap I will make with foam firing strips) and then butt up some rigid, open cell foam board to that. Is 1/2” a sufficient air gap or should it be thicker, nominally? How does the foil-faced foam board compare to using foil and then rigid foam board? Thanks, again.
1/2″ is the minimum air gap I’d go with. If you’re able to get a little bit more, go for it! But no need to have an air gap any more than 1″ for the foil; it would aid in ventilation with better airflow though. There’s probably not a lot of difference between foil + foam board and foil-backed foam board. You can check the specs to see what kind of aluminum they’re using, but it is likely to be comparable.
i live in new england. my biggest question is not whether or not to use a radiant barrier, but how much insulation works best with it? The house i just moved to has very little insulation in the attic. Should i beef up the insulation first or only add the radiant barrier?
Thanks
Lee,
Radiant barrier is NOT a substitute for standard type insulation. Check your local codes to see what is recommended for your area.
We are looking for a radiant barrier for an open beam structure that does NOT require an air gap. Possible?
Nope, not possible to have a radiant barrier when there is no air gap. Reason is here: No Air Gap? No Radiant Barrier.
Is there any way to add radiant barrier to an existing vaulted ceiling? There is no crawl space
Linda, there isn’t really a way to do it without pulling down the sheetrock and emptying out the cavities OR without losing ceiling height. The foil HAS to have an air gap in order to work, so you have to create that gap either in the cavity or on the ceiling, which decreases the height in the room.
Good evening. Thank you for sharing your knowledge. I live outside of Houston so it’s very hot and humid for the majority of the year. I want to insulate an open frame (2×4) shed that has a gambrel style roof. I want to use a radiant barrier (after an air gap I will make with foam firing strips) and then butt up some rigid, open cell foam board to that. Is 1/2” a sufficient air gap or should it be thicker, nominally? How does the foil-faced foam board compare to using foil and then rigid foam board? Thanks, again.
1/2″ is the minimum air gap I’d go with. If you’re able to get a little bit more, go for it! But no need to have an air gap any more than 1″ for the foil; it would aid in ventilation with better airflow though. There’s probably not a lot of difference between foil + foam board and foil-backed foam board. You can check the specs to see what kind of aluminum they’re using, but it is likely to be comparable.