Rain Screen Between Comfortboard and Cedar Shingle
user-6445625
| Posted in General Questions on
Dear Experts,
We are in Zone 6 in Maine planning for the following wall assembly:
gwb
intello plus
2×6
osb
tyvek
R6 Comfortboard
rainscreen
cedar shingle
Our question is: do we need vertical AND horizontal strips for the rainscreen or can we just use horizontal and assume the Comfortboard will drain?
Thanks!
Brad
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Replies
Not my area of expertise and hopefully you'll get other responses. But I've read around here that horizontal strips should suffice. Just leave a couple of inches between their ends. It's not so much a problem of shedding bulk water as maintaining a gap to allow shingles to be able to breath at their back faces.
That said, I've been specifying vertical strips and instead of individual shingles, using the shingles sold in strips, like Shakertown's "Cedar Shingle Panel".
There are other approaches as well. Here's a link to someone else who asked a similar question and got lots of replies. https://www.greenbuildingadvisor.com/question/furring-for-cedar-shingle-siding
Best practice, whatever approach you take, is to allow for ventilation at the bottom AND the top, using something like screening of Cor-a-vent strips.
Thanks this is very helpful input!
Can't answer your question, but suggest you try to source your shingles from Longfellow Cedar in Windsor ME. Nice people and really nice shingles.
brad17,
It wouldn't meet our code here for rain-screens, but practically you are fine. Although you lose a dedicated vented vertical drainage plane, individually installed shingles dry very well, especially with the gap and comfortboard behind. I wouldn't worry about only having a single horizontal layer of strapping in your case at all.