I have a 3 car garage in the house I bought outside of Houston TX in October. For storage purposes I put in an attic ladder and put down tongue and groove OSB floor sheathing in the attic to walk on. I wanted to climate control this space so I asked a guy at home depot about insulating the 2x6 roof joists. For some reason the joists were mostly spaced at 18". This is a 4 sided hip roof with about 6 soffit vents 3 on two sides and no ridge vent at all. The ridge is about 3 to 4 feet. I stapled (mostly) 23" wide craft faced R19 Batts to the back side of the roof between the 2x6's. For fire resistance and to take up the slack in the batts being 5" wider than the space between the joists I contacted my contractor to sheet rock the backside of the roof. He was going to build a knee wall and take out the purlins. He said everything I did was fine. Another contractor that comes highly recommended said that what I have done will create mold and rot my roof rather quickly. (LP Techshield roof deck) I have done all this work and now I am ****ting myself. Before I did this I bid out having the backside of the roof foamed, for price reasons I did not go this route. The second contractor said this too would have caused it to rot.
The second contractor is telling me I need to tear down all of the insulation and put in baffles, but how does this help when there is no ridge vent anyhow and the fact the roof is of hip design two sides are blocked off by the corner roof rafters anyhow, thus never allowing any air regardless of what I do from reaching the ridge.
I took me a very long time by myself and considerable funds to staple all of this batts to the roof joists. I just want to make sure I am doing this right.
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