Shed and porch roof insulation
Hey GBA’ers – I am currently at the point in my build and I am a bit stuck and would love some advice.
I have a shed /porch roof that was created from trusses (see pictures) and I am unsure how to insulate, and what get’s insulated and what doesn’t.
Question 1. If you look at image 8691, I believe what I should do is put blocking in-between the raised truss heel then put OSB which would be 14 inches deep so it would hold my blown-in insulation on the interior side of the shed roof. I would repeat this for the truss bays to the right and left hand side. Is this correct?
Question 2. Looking at image (FAC26) – should I sheet the lower side of the shed roof or simply put my final material? I’m leaning towards sheathing as I believe I could create a better air barrier. Thoughts and suggestions?
Question 3. Looking at image (FAC26) – do I need to insulate this area? Or on the exterior portion of the shed roof, that is the portion is the 100% exterior, do I simply leave as is and follow my strategy from question #1 above?
Thank you in advance for all the help! The 3rd photo is a shot from the interior.
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Replies
Josh,
I'll give your post a bump. Can you tell us where you are located? Climate may be a factor in how you approach this issue.
Hi Josh.
If I am understating your building correctly, I think the approach described in your first question makes sense for that area. You are defining the thermal boundary with the OSB and stopping the insulation there. (I am also assuming that this is a vented attic.)
As far as question number 2, you do not need to air seal the soffit here. The exterior walls need to be air sealed and that air sealing needs to be continuous to the air sealed ceiling plane inside, but not this area.
And when it comes to question 3, if that photo was taken from an interior space that will be conditioned, then yes, air seal and insulate the exterior walls and ceiling. If that is unconditioned space, treat it the same as the area in question 1.
I am in Minnesota, so it's super bold in winter months. But still don't know if you insulate the shed roof or if you just close it off to the interior?
Josh,
Which part is the "shed roof?" Just what is outside or including the area it covers inside the house? See my first response again.