Fixing an old cathedral ceiling
I will pose my questions here, and if needed the story and all details I know will follow. Currently my roof over just my living room, it was an addition, is a vaulted cathedral ceiling. It goes as follows, shingles>plywood>3/4″stryofoam material (seemed like actual styrofoam, definitely not foam board)>T&G.
That is the original layout, I have since added R-30 between rafters under original T&G and was going to do a new T&G ceiling on top of that, as that was what I was told to do by my roofer. I was not aware of the gap to let roof breathe for cathedral ceilings.
-Is the styrofoam material sufficient enough to let roof breathe?
-If not can I leave a gap of air underneath original T&G
-Is there any solution other than ripping roof off again to add baffles or whatever is required to create gap for air?
I am a recent new homeowner and have been introduced to the wide range of problems that come with being one quickly. My home, which is in climate zone 3, was built in 1958. Most of the house is solid, however the addition that was added is the problem. Not sure of the year for addition. It is just one living room with fire place (19×15), and a connected sun room (19×12), I will post pictures at the end. Now to explain the problem.
Soon after moving in I was about to paint the living room as I hated the color and there were just a few water stains on the walls, that my awesome home inspector told me were from a problem that had been taken care of. When I started drywall work the drywall was so moist at the bottom I could push my finger through with enough force. That led to the drywall coming down to reveal all kinds of rotted wood and other problems. The roof was inspected and actually revealed 4 layers of shingles! I was told the problem had been fixed, although not to code with all the layers. I had planned on replacing roof within a few years but not right away so I went ahead and put jacks on the roof and replaced the wall from the top all the way to the soul plate. I had noticed random drip spots all over the T&G but figured it was from the previous problem. Two months later during a bad rain storm my roof in the same room was leaking. Because of this I went ahead and figured replacing the entire roof would fix the problem. During this we found a boot had cracked and appeared to be the source of the leak, which may have been anyways. While doing the roof over the addition which has no attic we found there was only a layer of 3/4inch styrofoam material between the plywood and T&G. So I replaced a couple pieces of rotted plywood and figured I would insulate in the living room between the rafters from the inside. Insulate I did. I took the recommendation of my roofers, which clearly had no idea of cathedral ceilings and insulated using faced R-30. A friend told me I had not done it the right way and 5 minutes of Google searching last night showed me how what I was told to do, planned, and did for months is wrong.
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