I have to cut into my exterior wall to fix a leak. What’s the best practices to do so?
Attached, is a photo of my tiny house exterior wall. I will be cutting where the red rectangle is.
Unfortuantely, I am not able to access from the inside due to a one piece shower/tiling, etc directly in front of it. It’s simply not an option.
With that being said, I know it’s not ideal to cut from the exterior wall but I want to make sure 1) It’s weatherproofed and 2) Doesn’t weaken the structure stability.
My plan is to
1) Use a small oscillating saw to cut the rectangle of the exterior wall
2) Gently cut the house wrap with scissors
3) Cut the plywood sheathing
4) Repair leak
5) Replace plywood and tape seams
6) Repalce housewrap and tape seams
7) Replace exterior siding and caulk seams/paint over
A few questions
1) Does this seem like the correct way to go about this (given that I cannot access from the interior wall)?
2) Do you think a oscillating saw is the best tool to make the cut? I need something that can make very precise cuts so I can cut one layer at a time.
Thank you!
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Replies
The general approach is you repair cuts just like you would do a seam in the original material. So if your seams are taped, tape the cut. Housewrap should be shingled, ie higher layer over lower layer. If the siding had nails that penetrated the housewrap the housewrap isn't reusable, you'll need to put a fresh piece in.
It's really no more work to repair a big hole than a small one, so I would make the hole quite a bit bigger than you think it needs to be. Make each cut smaller than the preceding one so that your seams don't all line up. The plywood should be cut along studs so that when you put the piece back in you can fasten it to the studs.
The oscillating tool is a good choice for cutting the plywood. If you need help making sure your cuts are straight you can tack two pieces of scrap wood a saw blade's width apart to guide the blade.
What is the exterior cladding? That's such a small piece I would be thinking about popping the trim off and replacing the whole piece.
Thanks for the tips! Yea, the only reason I was aiming for a smaller whole is so I don't have to cut above the utilities. It would be much easier to turn off the power, and cut below it so I don't have to remove/touch any of that.
The exterior cladding is breckenridge plywood with 4x6 cedar trim beams.
Would it be possible to connect a metal drain pipe right through the wall (replace ABS pipe) so it's not possible for it to crack again?