I happen to be utilizing rigid breadboard fashion expanded polystyrene during the rim joists and imagined precisely the same can be set under the sheathing between the rafter bays, and with any gaps sealed having a urethane spray foam including Fill and Seal. Is there a top quality that makes spray foam acceptable and rigid foam unacceptable?
If you install 2x4s (or 2x3s on edge, set up with lengthy screws) perpendicular towards the rafters, you will address most of the thermal bridging worry with no really need to insert a layer of rigid foam.
For sure, from time to time you must plan forward to make sure that your rafters are sized sufficiently to permit for insulation and venting. To find out more on appropriate strategies to insulate lower-slope roofs, see this information: Insulating Low-Slope Residential Roofs.
2. It appears like that you are employing steel beams to body your hips. As I'm sure you realize, these steel beams are thermal bridges. All insulation needs to be on the exterior side in the metal.
It is kind of possible to design and style an unvented insulated roof assembly that performs properly, as long as you get the details correct.
A baby in the Depression, he started providing magazines on the age of 8, splitting his fifteen-cent an evening consider with his mothers and fathers, then delivering newspapers from uptown Collinsville the many way out towards the outdated leadworks Business, by way of bicycle.
I reside in northern Vermont, and I haven't got more than enough working experience with air conditioning to reply your issue about condensation on inside ducts.
Am i able to get some additional commentary on the "entire roof" of Ice & Drinking water Protect? I feel this had little to accomplish With all the failure. The rationale why I request is I've the same "entire roof" design arising, Nevertheless, the rafter bays are all straight operates with soffit vents, constant vent baffles (1/two" plywood) and ongoing ridge vent. Dense pack cellulose, 2" XPS below 2x10's, air restricted drywall (XPS could be sealed up much too).
Doug I concur, too many wrongs "overthinking" and overdoing. I at the time needed to resupply a physician creating an aircraft with dozens of the aircraft bolts given that they have been tightened to the point of breaking the bolts. Considerably less is much more occasionally... Combined with the KISS rule.
If not, he isn't going to reach refuse to put foam previously mentioned the sheathing, which might be greater and more affordable than fitting it among the beams.
We actually don't know if these roofs have right vent channels, or what type of vent baffles (if any) had been used to keep up the ventilation gap between the very best on the fiberglass insulation plus the underside from the roof sheathing.
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I've now insulated the steep sides of my unvented mansard roof with 6" fiberglass (And that i experienced it inspected), would you suggest I rip that out and click here for more info use spray or board foam? I have gotten conflicting details on whether or not to take care of it for a wall or possibly a roof.
Like Doug's structure, the focus is on making a large perm layer for drying to the outside, that will still allow venting even though blocking wind washing inside the fluffy stuff.