vertical wood siding constructibility question
I’m hoping to get your site-based constructibility feedback.
The exterior wall finish is vertical wood siding, probably something like cedar 1×6. Rainscreen application.
I know I can do vertical furring against the WRB, followed by horizontal furring, with the siding attached to the horizontal. But I’ve heard of people doing a single layer of furring applied at a 45 degree angle.
Do any of you have experience with that?
Are there constructibility advantages?
Are there detailing issues that need to be addressed, such as at corners or around openings?
I like the idea of the reduced labor, material, and assembly thickness of a single layer of furring.
Thanks for your input.
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Replies
jgsg,
I've never done it, but drawing it out there seem to be a few issues.
- Backing for the furring strips. If you wanted to hit studs, that could be a problem at corners and openings. However, our code allows furring to just be attached to the sheathing underneath if the sheathing is 1/2" thick on more.
- Venting at corners and openings. You are going to have to hold back the diagonal furring several inches. That might pose a problem with narrower siding like 1"x6"s.
- The number of cuts and waste. While I haven't used diagonal furring, I have done diagonal board sheathing, which takes exponentially longer than horizontal due to the angle cuts and differing lengths. It also generates a lot more waste. I'm not sure I couldn't do a wall with two layers of furring quicker than one diagonal one, using about 1.5 times the wood - remembering that to achieve the same spacing between fasteners on the siding, you will need to reduce the spacing of the diagonal furring.
As an installer I'd imagine the the more you do it the more you would work out the wrinkles, but the first time would probably be a bit challenging.
Thanks, Malcolm. That was helpful. It does sound like there wouldn't be much, if any labor savings in going with diagonals.
If doing both vertical AND horizontal furring I suppose the verticals could be something as thin as 1/4" rips of plywood, with 1x horizontals. The horizontals would attach through the verticals and sheathing, directly into the studs, getting a good purchase. Then the vertical siding would have 1x material to attach into. This would reduce the overall thickness of the assembly and keep trimming out the openings simple.
Jgsg,
Practically I don't see why not, although you might fall into conflict with code required depth of the cavity in some places. Ours wants a minimum 9.5mm drainage plane over the whole wall, unless you use an approved proprietary product.
Until codes are harmonized that's always going be the problem with generic plans. To meet disparate regional codes you have to go with the most restrictive requirements among the various ones.