A. There is a code requirement for a vapor retarder in some forms of assemblies, but there is no requirement for the vapor barrier. Your layer of rigid foam is currently a vapor retarder. No further vapor retarding layer must be mounted.
Really don't make any hasty decisions that you're going to regret. If vital, inform your roofer to prevent all Focus on this task right until this issue is fixed (assuming, obviously, that the roof sheathing is safeguarded by asphalt felt or a similar underlayment.)
Just like all kinds of vent baffles, it’s a good idea to pay attention to airtight design methods, especially if you will end up putting in air-permeable insulation from the rafter bays. Seal the perimeters of every panel with caulk, and tape the seams between panels with a higher-good quality tape. (For anyone who is setting up air-permeable insulation like fiberglass, mineral wool, or cellulose, the air flow baffle isn’t optional; it’s required.
A. To take advantage of the insulating worth of the rigid foam around the attic, you definitely need to seal up any attic vents, so you unquestionably don't want to make a ridge vent.
Employing ventilated nailbase panels is a perfectly great way to build a cathedral ceiling. A similar rules use as when utilizing SIPs: be sure that the seams are sealed to get as airtight as you may make them, and be sure that the whole R-price of your roof assembly fulfills or exceeds minimum amount code R-price requirements.
I have a 50 12 months-outdated seasonal cottage within a northern climate. The simple six/12 gable roof is composed of precise 2x6 rafters (24" oc), sheathed with 1/2" plywood and lined with asphalt shingles. There is no insulation from the ceiling and I suspect little to no powerful insulation while in the 2x4 partitions. In the summer the warmth gain inside makes residing Just about unbearable. I think that the most important bang to the buck would be to deal with the ceiling insulation concern to start with, but would want to retain the inside look.
Why not just get it done proper as well as Develop with strain taken care of roof sheathing. Even regular plywood can take care of wetting cycles again and again greater than our primary Tremendous economical OSB.
"The normal roof ventilation prerequisite Employed in constructing codes and asphalt roofing suppliers requires one square foot of "Internet absolutely free ventilation location" For each and every three hundred square toes of ceiling region (attic ground place) when vents are evenly divided — half of these superior over the roof within the ridge, gable, or possibly a substantial roof, and 50 percent minimal around the roof on the eaves.
As building scientist Monthly bill Rose has revealed, code specifications for roof venting were being by no means based on study or scientific rules. In a very nicely documented JLC
If more helpful hints you would like endeavor a midway Resolution that may or may not work, you may cut out many of the drywall close to the ridge, and put in spray foam insulation within the underside from the roof sheathing, just in the region near the ridge beam.
Be certain the roof assembly is as close to airtight as you can also make it. If you are description using fluffy insulation, you need two air obstacles: just one below the insulation, and a single earlier mentioned the insulation.
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It sounds like you've an present roof with tile roofing. I am guessing that you are creating from Europe. It sounds like the insulation includes "tight-fitting Wooden fibre board" among your rafters -- thickness and R-benefit aren't specified.
Electricity codes set up least R-worth requirements for roofs and ceilings. There are many achievable code compliance paths; most builders select the prescriptive route, which sets forth minimal R-values for roofs and ceilings inside of a prescriptive desk.