I do not imagine that the weight of plywood or OSB will probably be a problem, but if you are worried about the extra body weight, you can generally seek the advice of an engineer.
With This technique , there's no problems with an entire peel-stick roof underlayment along with the deck is there? I've a metal roof on this job along with the underlayment will probably be entirely adhered for the roof sheathing.
You say "You don't want an interior vapor barrier," but you also declare that "You will need a great air barrier on either side of your fiberglass batts." The latter would transform an inside vapor barrier not so?
It's absolutely not limited to an R eighty Passive Property roof. Get out the parallel chord trusses and slim it up.
When roof air flow will help dry out moist roof sheathing, it’s necessary to limit the stream of water vapor escaping from your house so the roof sheathing in no way gets damp to start with.
I now realize that stucco cannot be applied to a roof, so I'll revert on the a steel roof, but nonetheless want to possess an unvented attic. I've study via "Creating a conditioned attic", and am nonetheless not sure as to The easiest method to move forward.
Nevertheless, I feel you will be Erroneous regarding your asphalt felt; I question In case the felt is impermeable to drinking water vapor. Most varieties of asphalt felt are considerably permeable -- typically 5 perms when dry and nearly 60 perms when moist.
I'd include to Martin's list of products for rafter vent channnels, fiberboard sheathing. I exploit I joists for vented cathedral ceilings and staple one/2" fiberboard to the bottom of the top wire in the I joists. It can be ripped over a desk noticed and installs speedily, fiberboard Recommended Reading does Possess a substantial perm score and could let modest quantities of dampness to go through in to the vent space.
Will not make any hasty decisions that you'll regret. If important, inform your roofer to prevent all Focus on this task until finally this issue is settled (assuming, of course, additional hints that your roof sheathing is protected by asphalt felt or an identical underlayment.)
Ensure that you set up insulation that provides at least the least code need for ceiling R-benefit. Insulation that exceeds the least code requirement is a lot better.
I previously sprayed and Lower cobbled four inch of closed cell. I will redo the roof future yr, but I suppose now it is too late to consider eps/iso on top of roof since i currently unvented the attic.
Martin, I am grateful for your time, and right after reading through lots of within your replies, I am able to see you happen to be passionate about developing issues right. Right for people today, as well as Earth. Thank you for Anything you do!! Ryan Nelson
Will you be imagining the 'flat' vented cavities will not likely offer the assembly using an exhaust route for humidity?
I'm opening up my house and installing cathedral ceilings, I just preferred to confirm my system since I obtained next thoughts looking through A lot more over it. My unique conclusion was to go along with a vented roof process and R38C batts. I go through a good deal about different techniques and it even now seems to me that this is the best. Livint in Atlanta GA We have now to handle the two incredibly hot humid check this summers and chilly winters, so humidity Regulate is a dilemma, that's why I think the vented method is the best. Anyhow, I am right down to the rafters and roofdecking and furred out the present 2x6 with 6" metal studs, so I've about 11.5" for insulation. Mt program was to make a constant ventilation underneath the roofdeck, my dilemma goes towards to make use of baffles, xps board Create baffles or insect monitor nailed at furring strips to permit to the airspace.