In case you are building a cathedral ceiling, the largest air-barrier blunder is to install tongue-and-groove boards as your complete ceiling devoid of to start with putting in taped gypsum drywall. A board ceiling is notoriously leaky, and this sort of ceiling is frequently connected with roof sheathing rot.
Pertaining to dense pack cellulose: not sure why dense pack might be negated - I believe it properly suited.
Polyiso is applied continuously for this kind of roof assembly. Polyiso does not outgas. It is much more eco-friendly than XPS -- and it's got an increased R-value per inch.
Yesterday we blew the insulation and put in the SIGA Majcoat to the CAPACES Leadership Institute. There was much more than 8,000 Cubic ft of insulation to install, so our insulators had two of their blower vans and a very good crew on internet site. They had been blowing cellulose as fast as they could plus the the rain was heading our route. A lot less than forty five minutes following the insulation was done we had finished the Majcoat and had been fast paced taping seams.
The precise design and style proven was for just a Passive House. The roof thickness & usage of a company cavity may look like overkill for many tasks, but If you need an airtight lid, a service cavity can get you there - forever... And let you wire and lightweight the interior.
Am i able to get some much more commentary within the "total roof" of Ice & Drinking water Protect? I feel this experienced hardly any to carry out with the failure. The explanation why I question is I've an analogous "whole roof" style and design arising, On the other hand, the rafter bays are all straight operates with soffit vents, constant vent baffles (one/two" plywood) and steady ridge vent. Dense pack cellulose, 2" XPS under 2x10's, air limited drywall (XPS may very well be sealed up also).
Thanks for that input. I see a pay a visit to using a structural engineer and 35 sq. of polyiso in my in close proximity to future.
A. There exists a code prerequisite for any vapor retarder in some kinds of assemblies, but there is no requirement to get a vapor barrier. Your layer of rigid foam is by now a vapor retarder. No further vapor retarding layer should be put in.
Alright, I had been figuring that the whole from the rigid foam + look at more info cellulose needed to be a particular R-value together and were considering using a lot less rigid foam. I have been studying about different sorts of cellulose. Given that I am setting up from higher than would something like stabilized cellulose get the job done since it has just a little h2o extra?
Q. "The air barrier is always to be positioned over the pine T&G ceiling and underneath the foam. Would you propose that we use one thing which can be the two an air barrier and a vapor barrier?
Nicely the roof is going on with the visit this website first layer of insulation (on-top the purlins, underneath the roof sheeting). There appears being plenty of Room left during the four" purlin cavity for the next layer of R11 for being installed with none modification.
I might like to use the exterior wall and roof sheathing as my Main air barrier; cdx plywood with all seams taped, which kind of forces me to maintain the roof venting along with the roof sheathing, when you explain in paragraph 7 of this post. I would choose to use Solitex Mento being a permeable roofing underlayment, as well as a WRB on vertical walls, and a couple of layers of cross hatched 1x4 strapping over roof ply and Mento; a person functioning down the roof slope, nailed into the rafters, and the second run horizontally about them to assistance corrugated metal roofing.
I believe you necessarily mean this: Your cathedral ceiling is presently uninsulated. If you are indoors seeking up, you may see your rafters. Previously mentioned the rafters you could see a layer of boards. Is always that suitable?
That said, if your local creating inspector approves within your program, and For those who have loads of your time with your arms, and you are effective at executing a meticulous career of air sealing, it is possible to go ahead and attempt the Slash-and-cobble solution.