Expanding 24″ oc Stud Bay for 24″ Duct Pipe
Hi, new to the forum. I am installing a spray booth in a stick framed building, where the exhaust pipe needs to go through the center of a outside wall stud bay (load bearing). The issue is that the duct is exactly 24″ od and the opening is about 22.5″ — close, but not close enough. I need about an extra 3/4″ on each side to clear. It seems I have two ways to go: 1. Sister a 2×6 on each side of the studbay and notch out a small portion of the existing studs to fit the pipe. 2. Reframe opening as you would with something like a window to get the clearance I need. Since it is past 24″ oc it appears I would need to put in a header. Not sure of the size. Just looking for advice/ideas on how to deal with this situation in a safe/up-to-code manner. Thanks for the help, Frank
Replies
Use a reciprocating saw to cut the nails at the top plate and bottom plate of one of the studs. Also, cut any nails or screws in the drywall or outside sheathing connected to that stud. Use a hammer to knock that stud over 1.5 inches and you should be fine.
Are you absolutely certain the duct isn't oversized and couldn't be stepped down? A good HVAC shop could easily make you a fitting which would accomplish the slight reduction you need. If the duct is already oversized for the purpose at hand (as it often is)then reducing it this slightly won't hurt performance.
Honestly, you could probably just do it yourself too by clipping the corners and bending them in.
What is the duct made out of? Could you make it into a little bit of an oval? The air won't care.
I'm picturing a round metal
I'm picturing a round metal duct. If this is right, just deflect it through the stud bay. This will result with a smooth transition, and only a slightly smaller cross sectional flow area.
I agree. I wouldn't mess
I agree. I wouldn't mess with anything. I'd just beat it to fit and call it a day. I suspect its probably oversized to begin with so this slight change won't hurt a thing.
I'd just sister, as you
I'd just sister, as you suggest -- no need for a header, since you aren't substantially exceeding the stud pitch. In theory you could get away with sistering/notching on just one side, but it "feels" better to do both.
I'd sister on one side and
I'd sister on one side and cut the existing stud completely rather than moving a stud that's already there. It's quicker and you retain the attachment to the exterior osb/plywood/siding.
On the other hand, if the hole doesn't "want" to be in the middle of the stud bay, it's really not that much more work to install jack studs and properly header off a couple of stud bays. I wouldn't avoid that approach just because fitting between studs is a hair easier. For a small project like this the materials cost is trivial compared to the labor.