Two stud corners, exterior insulation, and hardi trim.
I’ve been trying a few of the popular advanced framing building details by drawing them in CAD, and I’ve come across a few questions / observations that I’d like input on. I’m using 2″ of exterior insulation and furring strips, for either LP SmartSide or James Hardi siding.
The California corner provides room for more insulation, and uses less lumber, but it seems to leave very little in the way of nailing edge on one side. For brick, this doesn’t seem like a huge issue. For board sidings, this seems to not provide enough room for screwing in a furring strip, and getting the trim on right. I suppose it could work if the furring strip extended out one way, but that seems flimsy.
That situation can be remedied by going to a three stud corner, essentially moving the California stud (I just made that up, not sure what it’s called) flush with the exterior plane. That doesn’t seem particularly stout either, even when supported on the three sides. I suppose it works fine as a nailing edge, but flexible compared to traditional 4 stud corners.
Near window openings and doors, the removal jack studs, and extra king studs leaves me in the same situation, especially with window bucks for a flush aesthetic with the trim and siding. Again this seems to work fine for brick cladding, but not that well for exterior insulation with furring strips. I’ve found myself adding king studs to work around this, or turning one flat towards the exterior to have a wider nailing surface, but still doubting its strength.
This is in regard to advanced framing, but it seems that exterior insulation actually requires a little more lumber than ‘advertised’ to get the details right, while being structurally sound, and being practical. Am I thinking about it wrong, or is this common, and typically worked around in the field?
Thanks,
Kyle
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Replies
I use wider plywood strips at corners. These should be wide enough to reach past the corner stud for support. You can also staple the strips together at the corner for additional support (I have thin brick veneer over a corner detail like this on 2" foam).
For tricky areas it is always better to go with plywood sheathing. This will hold screws even if you can't get directly at the stud.
Be careful with advanced framing details, some of them such as single top plate are not worth the savings. This is pretty bang on:
https://www.proremodeler.com/getting-real-about-advanced-framing
Good points. Agree with your approach. Good article too...it was spot on.
Thanks for the link Akos!
That article pretty much sums of most of the binds I was getting into when I was trying some of these out. Some things made sense, others seemed hard to build for little gain.
The one item that is not often talked about with advanced framing is moving your headers into the rimjoist. Provided your structural engineer is cooperative, you can eliminate most of them. Sometimes it is just upsizing the rim joist thickness or doubling it up over the window. It does mean joist hanger for any floor joist/truss over the opening, so it adds a bit of extra labor.
It doesn't save cost but does increase wall insulation and also lets you build much larger windows.
Akos,
Thanks, good article. The only one they recommend I'm not sold one is gapping the partition walls for drywall. I think it causes more problems that it solves.
Malcom,
For those of us with less experience, would you care to elaborate a little on that point?
Kyle,
Leaving a gap and running the drywall behind the partition walls causes a few complications.
- You can't have electrical, plumbing or ventilation runs between the two.
- You can't lap the top plates.
- Not ending drywall sheets at the corner usually means another butt joint in the field in the adjoining rooms.
- You can't air-seal the sheets behind the intersection and still have a gap where the ceiling drywall is missing.
-If you ever open up that exterior wall, you have no backing to reinstall the drywall.