Leak and sheathing rot behind the end of a soffit. How do I fix this?
Hey folks, looking for some advice because I don't know how to proceed.
This house came with vinyl siding and I noticed rot under it. The rot terminates up high behind where this soffit meets with the exterior wall. I need to get in here to figure out how water is getting in and then make necessary repairs, but the soffit is really in the way.
I've already removed the rot lower down - I had to remove vinyl siding, a layer of foam board, a layer of rotten OSB, the original rotten siding, and the original rotten sheathing. All of those layers are still present behind this soffit.
When I take the soffit vent off, there's a layer of OSB directly above it. Really don't know how to gain access here.
I always say that owning a house is mostly water management - making sure water goes where it's supposed to go, and doesn't go where it's not supposed to go.
I'm almost positive it's a flashing/counter flashing failure on the roof above the soffit. It almost always is. One bad piece of flashing halfway up that roof could be it.
Check that the gutters aren't holding water though. If the siding detail behind the gutter endcap is bad, and the gutters endcap is leaking, that could do it.
And remember water doesn't always run downhill. That shit can and will go straight up a wall if the circumstances are right.
I'm assuming there's a rafter tail above the OSB that's above the soffit panel. So even if you cut that OSB you'll have the rafter tail to deal with. How does the roof meet the exterior wall above there? Is there flashing? Could that be where the water is intruding? The sheathing and foam was installed before the siding trim and gutters were there so it's hard to imagine you getting any easy access unless you're willing to cut a lot of things off and re build them.
Good point on the rafter tail. I'll look in the attic in that area to confirm.
Yeah there's flashing above there and it's possible this is the source of the leak.
I'm afraid what I'm going to have to do is take all the siding off above here to expose the flashing and inspect it and repair. Then to remove and fix the rot I'm gonna have to take everything apart to get into that area behind the soffit - remove the gutter, fascia, etc to gain proper access
Step flashing and diverter at the end isn't working right. The last piece of step flashing above the gutter should have a bent out piece to get water running down the wall above to go into the gutter and not just run down the wall. I'd also be very suspicious the siding isn't installed correctly there as well as it shouldn't let water behind it.
I'd get an exteriors contractor to come and look at it, and see if they can bring the two problems together to be fixed.
No diverter is present there at all. There's a bunch of things going on here that could be causing this problem and I think it would be best to address all of them at once:
No diverter
No drip edge present along gutter, and I've seen water drip from soffit vents. It's possible water is coming into the damaged area from where the soffit meets the wall
Vinyl siding was installed over original wood composite. It's questionable whether the step flashing is effective given the setup
Gutter potentially too small - I have to clean it out like 6 times a year even with gutter guards over most of it
So the roof line meets the wall above this? My first suspect would be the step flashings along that wall (assuming a shingled roof). Often what seems like a small or minor detail in the way these flashings are done can mean they work great, or water gets in over time.
I think people have given the requested advice, so I'm just going to say unless you know the age of the soffits, be a little bit wary as there may be asbestos fibre board behind the PVC outer, shouldn't matter unless disturbed, but just be aware