WDR Roofing Company Austin - Roof Repair & Replacement
Austin, TX, USA
Insulated cathedral ceilings are a relatively modern phenomenon. The craze for insulated cathedral ceilings (and wonderful rooms) really took off while in the seventies and eighties, when illustrations commenced showing up like mushrooms following a heat rain.
The bottom line is that, as long as your roof sheathing is pretty dry once the roof is closed in, you need to be wonderful, even without outward drying. I might go in advance an put in the peel-and-adhere membrane within the valleys and within the eaves without worrying.
It really is safe to say that an present household doesn't have very good roof ventilation if there aren't any soffit vents or ridge vents. It's also Protected to state that, whether or not you can find soffit vents and ridge vents, the roof isn't ventilated if it incorporates valleys, hips, dormers, or skylights.
Thanks on your suggestions, Martin. Eco-friendly Constructing Advisor has been the best for answering unique questions I've experienced through the basement many of the way to the roof. I wouldn't be able to create my own household solo like this without you together with other visitors assisting me out with information.
I doubt that the condensation is occurring in opposition to the cold ridge beam. Somewhat, I feel it is likely that condensation is going on on the underside of your ridge shingles or the underside in the asphalt felt underlayment.
With my house the center area (20ft) is vaulted, a 3x12 slope and has eight recessed lights during. I have experienced leaks in several locations On this portion of the house, the leaks come about with the thaw and refreezing. It received the point last yr wherever I had to shovel the whole roof after each snow drop.
No matter whether you choose to make it vented or unvented, get the small print right — for the reason that every single cathedral ceiling offers opportunities to help make significant problems
Q. "I have just lately received use of low-cost roofing polyiso -- black backing on either side. website here My experience is that Placing this backing from the rafters in touch with that vented air may be inviting a mould problem, and when i facial area it towards the space i eliminate the radiant look at these guys barrier."
As the house flexes with alterations of temperature It is really achievable, even probably that some of the foamed-in air sealing will leak. It might be worth accomplishing two" of open cell foam on the interior aspect of which would be a more versatile and reliable long phrase air seal.
If you need to install a combination of closed-cell spray-foam about the underside with the roof sheathing and air-permeable insulation in between your rafters — an strategy at times named “flash and batt” — the developing code requires that spray foam (or, arguably, rigid foam insulation) be “applied in direct Speak to with the underside of your structural roof sheathing” and that the foam insulation satisfy the requirements “laid out in Table R806.
two. Everytime you install fiberglass batts, air barriers are a lot more important than vapor Management. You need a good air barrier on each side of one's fiberglass batts.
Back on the vent idea. I really Assume venting a roof that is airsealed in the interior very well and designed without vent chutes is potentially the best way to construct cathedral ceilings.
I am not a enthusiast of entire peel-and-stick roofs, for a variety of causes. useful reference But your plan will most likely be great. Just ensure that your roof sheathing is dry over the working day you install spray polyurethane foam -- since the sheathing will not be drying a great deal in possibly path just after It truly is encapsulated amongst peel-and-stick membrane and spray foam.
If you wish to Blend air-permeable and air-impermeable insulation, There's two feasible solutions to progress. A single selection (in accordance with the code) involves: “Together with the air-permeable insulation mounted straight below the structural sheathing, rigid board or sheet insulation shall be mounted right over the structural roof sheathing as laid out in Table R806.five for condensation control.”