Tyvek on small bumpout
I’m building this doghouse for a new gas fireplace. As you can see, foundations poured and joists and subfloor in. All inspections passed so far. The walls are framed but not nailed up yet because I have a Tyvek issue.
As you can see, I plan to nail the 2x4s to the existing siding, then wrap with Tyvek and then cover with T1-11. My question is what to do where the new side walls hit the house? If I wanted to make a proper inside corner, according to all of the videos, I should cut a few inches of siding away from the house where the new wall comes in and then tape the new Tyvek to overlap the exising. But to do that, I have to cut away a few inches of siding, and then replace that with new siding, and it seems like that just introduces more opportunities for water infiltration than I would be supposedly stopping. And replace siding all the way up the wall to avoid a joint halfway up, or at least as far up as the roofline on my doghouse.
Here are my other solutions so far.
1. I could wrap the Tyvek around behind the new 2×4 so it’s nailed between the 2×4 and existing siding.
2. I could extend the Tyvek along my new wall and onto the exterior of the existing siding, but am not exactly sure how to finish it. I will put a 1×2 or 1×3 on that inside corner to match the rest of the trim treatments on the house. So I could staple it an inch away from the corner and then run tape over it, then nail up the new trim and put a heavy line of caulk along both edges of the trim. That seems like a reasonable solution to me so far.
What’s the best way to deal with this?
I live in Northern Nevada, a very dry climate.
Thanks in advance.
Picture wasn't showing up - fixed
Don't know why I had trouble getting the picture to show up, but now it seems to be there.
What do you plan to do for the top edge where your new roof meets the siding?
Roof will match roof on wall above
I plan to cut into the siding to get the flashing behind the T1-11, same as was done on the shed roof above my project.
So I'll have a basically 2 inch slot across the wall to get the flashing behind the siding.
Since you're going to cut the top for roof flashing I'd continue that cut to the closet joint on each side of the bump out and remove all the siding in between. That gives you the space you need to flash your Tyvek to the original structure. In fact, I'd use Zipwall and a liquid flashing on those corners rather than plywood and Tyvek but either will work. Use a Z flashing to protect the top of the new siding as well as your head flashing over the roof and you're good to go.
I agree with CutA on most of his recommendation, except that I prefer a metal insidecorner flashing with a kickout at the bottom.
It's my house, I never want to relay on chemicals when a metal flash can be used. Metal is forever(think roofs)
You pretty much boxed yourself in by not removing siding first.
The curse of the weekend DIY-er
I debated about taking off the siding, but I really didn't want to puncture the envelope of the house any earlier than I had to, and since this is an evenings and weekend project and my kids are busy, I'm glad I didn't have to cut the siding yet. But it's about time, so I'm going to have to bite the bullet. And I also agree with metal flashing.
I wish I had a buck for every piece of rusted out metal flashing I've removed in the last 50 years.
Aluminum doesn't rust.
Where did you read that? You need a new source. Aluminum oxidizes even more quickly than steel. That process is called "rust" on ferrous metals and "oxidization" on aluminum. Same process. It happens so quickly with aluminum that electricians using aluminum wire have to coat the stripped wire with anti-oxidation paste as soon as it's stripped. A piece of aluminum flashing nailed on with a bright or galvanized nail and in a damp location will be riddled with pinholes in a year or so.
All metals corrode under the wrong conditions. "Rust" is the reddish corrosion formed on iron and a few other metals. And one of the good features of aluminum is that the oxide that is formed on it, in most conditions, is "tight" to the metal (unlike rust on iron), slowing further corrosion.
Once again, where did you read that. It's wrong, as usual. But hey, I'm willing to bow to your superior experience. Tell us again about your construction experience.
I was not familiar with Zipwall or liquid flashing. I will check those out.
Zipwall also makes a flashing tape that works great as well. It will probably be easier to get then the liquid.