Certainly, you may still have thermal bridging from the rafters. But you will not have any moisture issues.
If you decide not to extend the rigid foam above the parts of your roof that have a standard vented attic, your builder (or an architect) can come up with a trim detail that you simply may be able to Are living with.
You can skip the tape on the highest layer of plywood to same some time and expense. Which is almost certainly what I would do if I were being you. That said, there is no hurt in taping the seams of the very best layer of plywood.
BTW, for that foam sort, I'm leaning towards XPS since one) I possess the effect that ISO is rather fragile, which include if it receives in any respect moist, and 2) the opportunity of long run outgassing with ISO. Ideally any such outgassing would go upwards and outwards as an alternative to downwards into the house interior, but the chance that it could outgas into the interior definitely problems me.
Thanks, Martin and Stephen. The good thing is we're in a very situation the place we will pause and rethink, as the new felt continues to be put, Nevertheless they haven't started off putting in shingles still. I will go over the problem With all the contractor all over again. I might be able to get him to reconsider.
I have to question In the event the failure inside the photo might have occured If your hip and ridge was vented and anything else a similar?
Certain it's loads of issues. It looks like less trouble that the read here element posted as instance during the blog higher than and makes use of no foam... Which happens to be a "biggie" for me.
I haven't helpful hints got lots of home higher than or below the roof structure for insulation / venting. Would a flash / batt unvented assembly work less than The only sheathing deck? My insulator has performed A good number of of these domestically.
You say "You don't want an inside vapor barrier," but In addition, you declare that "You will need a great air barrier on both sides of one's fiberglass batts." The latter would turn into an interior vapor barrier not so?
Initially, could it be simple to detect whether or not a roof is ventilated? If no soffit vents or aspect vents are seen about the roof from the ground, does that mean the roof isn't ventilated?
You presented a connection, however , you under no circumstances stated which illustration you were referring to during the article you connected to. I am guessing you were speaking about the illustration that I have reproduced under.
Q. "For an unvented construction without insulation over the sheathing, how about working with Wooden fibreboard concerning the rafters instantly down below As well as in contact with the sheathing?"
Q. "I are actually making use of blog here rigid breadboard type expanded polystyrene within the rim joists and assumed exactly the same could possibly be place under the sheathing among the rafter bays."
Relating to installation: Even though it's been successfully put in in Europe for quite some time, we've just gotten the material, and so we anticipate receiving it on a task web-site before long and actually installing it - not to mention, reporting again the way it went.