A-Frame interior roof insulation
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I have an A-Frame house in the Pacific NW. Build in 1960’s insulation was not.
I need to insulate the inside of the house with something. What is there now new comp roofing, Water/ice/snow vapor barrier. 2×6 T&G car decking. The inside is exposed 2x6T&G and nice large exposed wood beams.
Since removing the very old shake roof and installing the above we have much more humidify in the house. I run a dehumidifier which keeps things inside air dry.
What I want to do is add a board type insulation to the decking (ceiling) inside between the 8″ wood beams. Maybe 2″ to 4″ think and then install new 1×6 T&G over that. I will still have the same look inside and wife will be happy seeing the beams and warm.
Questions
1. What type of insulation board should I use.
2. Do I need a vapor barrier over the insulation before I install the decking or do I need a vapor barrier at all? I am sealed now between the comp roofing and the outside or the decking.
I only want to do this once, so looking for advise.
Thanks.
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Replies
It's a shame the roof got re-done. The best way of insulating those types of A-frames is continuous rigid insulation on top of the t&g sheathing. I'd still be inclined to consider that even if it meant another round of shingles.
Well that is not an option.