Timber Frame Cathedral Ceiling Question . . .
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My name is Shane,
I live in Western Washington (Climate zone 4c), and have been trying to come up with a roof design that compliments the vaulted ceiling and I found this and was wanting to replicate it in my own build. I do understand this was designed around a colder climate zone. It seems simple and straightforward. Here is the link Insulating a Timberframe Roof Build Up | Ana White (ana-white.com) The only difference I would make would be to utilize fluid applied barriers (Prossoco) instead of peel and stick or the like. I know a little bit of building science (just enough to be dangerous). I welcome any feedback on this. Thank you.
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Replies
It looks great but not cheap or easy.
My guess is for way less than the cost of the materials needed build that roof you could have a crew set a truss roof with a flat ceiling with twice the R value and half the surface area to losing 1/3 the heat.
Walta
I already have the plans engineered and stamped, and in those plans we are utilizing all the upstairs space, which means not your typical truss roof with a flat ceiling. It is essentially a timber frame house with some modern connections. Thanks for the feedback!
Shane,
Once the t&g decking is on, there isn't much difference between the roof assemblies which will work for timber frames, and other roofs. The one you posted will work well, as will any of the other choices in this link. https://www.greenbuildingadvisor.com/?s=five+catherdral
One problem with t&g decking is air-sealing where it goes over the exterior walls. It needs to be bedded in flexible caulking, and have that caulking applied to each groove as it is installed.
Good luck with your build!
I hadn't considered that issue of air sealing where it goes over the exterior walls, thanks for the work around. My plan once the frame is up, t&g decking installed, and sheathing to is to apply something like Cat 5 over the whole thing (roof decking too) I am thinking that would help with the air barrier issue too. Thanks for taking the time to answer this question.