The very best Option is to handle the situation from above, by adding a substantial degree of rigid foam above your current roof sheathing. It is possible to Construct up the layers you, of You should buy SIPs or nailbase panels.
Martin, re: switching the attic about the second story bedrooms into a conditioned attic and sealing the soffit vents.... Previous to this latest concept about insulating with rigid foam on top of the cathedral ceiling, we had been intending to cut a ridge vent into your gable ridge, in an effort to meet ventilation code prerequisites. Now We now have eave vents as well as two quite worthless gable vents, one on each side.
A. The air barrier is usually a vapor barrier, as the rigid foam is also very likely to certainly be a vapor barrier (or close to it) in almost any circumstance.
This roof assembly appears to be like really cathedral however, if i fully grasp properly its not vented whatsoever, but has generous previously mentioned sheathing foam. Is that this regarded a vapour Protected assembly thinking about this post suggests "Put in rigid foam insulation earlier mentioned the roof sheathing and air-permeable insulation involving the rafters.
Your strategy to install a stack of rigid foam rectangles in Each and every rafter bay is called the "cut-and-cobble" way of insulation. It's a method usually chosen by homeowners, but never chosen by insulation contractors.
This information was incredibly enlightening and appeared to provide a good deal of recommendation on cathedral ceilings. But what what my ideal storm? Your house is 30 several years outdated (80's) and im certain the ceiling is not air limited. I wish to do one thing this summer months/fall to test to Check This Out fix these leaks but I'm apprehensive that regardless of what I do wont perform and will become a squander of cash, especially given that I havent heard about a strong solution.
My emotion would be that the dew place profile would find yourself from the XPS foam board, therefore a VB really should be placed on to start with deck. So as of assembly:
Thanks to your response Martin. Would you still be happy to use that unvented approach for your renovation situation exactly where There's non-breathable membrane (eg bitumous 'felt') previously mentioned good board sheathing?
Thanks yet again. The roofer agrees that 2x4 framing to raise the height more than the vented Recommended Reading attic can be a workable Alternative to match up the roof lines.
4. Upon getting R-20 or R-25 of rigid foam on top of your sheathing, you'll be able to properly insulate below your sheathing with almost any sort of insulation you need to use to provide your insulation approximately minimum amount code demands.
Have home about garage Centre with closets on either side among the closet kneewalls and also the eaves. Insulation above the home area is six inches of foam slabs sealed by "Excellent Stuff" spray-in foam. Above this ceiling visit this website foam and under the roof plywood, you will discover 1 inch x 20. inch unobstructed foam encased ducts concerning the rafters for venting towards the roof peak vent. The side sections outside the house the knee walls are insulated with rolled fiberglass fiber with durovent ducts among the insulation plus the roof plywood. You can find sizeable soffit vents at The bottom of the durovent ducts.
A. I agree. In light-weight in the odor difficulty, I don't are convinced my suggestion to utilize Ice & Water Defend was a great 1 -- so I withdraw it.
one. You do not need an interior vapor barrier. In a very incredibly hot humid local weather, the vapor travel is usually from the exterior toward the inside (assuming your constructing is air conditioned). When your constructing is not ever destined to be air conditioned, the vapor drive will still be from the outside to the inside, but there will not be A lot vapor generate.
I've already insulated the steep sides of my unvented mansard roof with six" fiberglass (And that i experienced it inspected), do you recommend I rip that out and use spray or board foam? I have gotten conflicting data on no matter if to take care of it to be a wall or perhaps a roof.