Fixing Tyvek Cut Short
So I am in the process of fixing flashing and trim on a few penetrations on my house. By fixing, I mean adding flashing and trim as the originals were just drilled through the siding and sheathing.
It turns out that the siding installers had cut the tyvek back for the starter strip so the last couple inches of the OSB sheathing is u protected. No major damage in this area, but The WRB should be fixed. This is 2010 construction in MA, and we are the second owners.
My plan is to use 3m all weather tape over the starter strip and under the tyvek. Alternatively I could go right over the tyvek.
I am also think to use liquid flash between the bottom of the sheathing and foundation. This would be a little tricky with the starter strip on, but I would like to leave it in place unless someone convinced me otherwise.
The plan is to eventually work around the whole house.
Does anyone have input or guidance to do this dofferently than I propose here?
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> My plan is to use 3m all weather tape over the starter strip and under the tyvek. Alternatively I could go right over the tyvek.
I'd be careful about going over the Tyvek, because if there's any chance of water getting behind the Tyvek above this point, you could be trapping it at the bottom by taping the face of the tyvek to the sheathing/starter strip.
As an alternative to 3M tape, you could also get Henry Blueskin in relatively narrow lengths and run a band of that around the building perimeter, lapping Tyvek over that.
Always lap WRB, never reverse lap. Any tape should go under the original Tyvek.
I hope those two pipes are not air intake and combustion exhaust for a furnace. They can't be that close. One of them needs to be extended to have between 1' to 3' between them depending on BTU.
Okay, so I will put the tape under the tyvek.
I know there is some debate about taping the bottom edge of the tyvek closed. I think something along the lines of if you have pooling water you have a problem anyway.
Does it seem worth it to liquid flash the bottom edge to the foundation? The sheathing is not taped, anywhere. The inside rim joist is ccSPF from the top of the foundation up to the underside of the floor.
Akos, those are the gas furnace intake/exhaust. I have the termination kit removed, but it is this style: https://www.homedepot.com/p/Rheem-2-in-Horizontal-Vent-Termination-Kit-for-High-Efficiency-Tankless-Gas-Water-Heaters-SP20285/202584270?mtc=Shopping-VF-F_D26P-G-D26P-26_10_WATER_HEATERS-Rheem-NA-Feed-PLA-NA-NA-WATER_HEATERS&cm_mmc=Shopping-VF-F_D26P-G-D26P-26_10_WATER_HEATERS-Rheem-NA-Feed-PLA-NA-NA-WATER_HEATERS-71700000033150354-58700003868932471-92700031086650216&gclid=EAIaIQobChMI3c676KWv6wIVFY3ICh0zQAthEAQYAiABEgI0MfD_BwE&gclsrc=aw.ds
I haven't worked with the 3M tape, but if it is sticky enough and wide enough, you could run the tape from up behind the Tyvek, down around the bottom of the OSB and onto the foundation. Some tapes might require a primer to stick to the concrete. I would also reconsider the starter strip. It's not very difficult to remove and either reinstall or replace. That would make taping much easier.
The vent termination kit should be fine, so long as it is listed for use with your furnace.
I have thought about the approach you describe. My only concert is that I can only put about 3/4" of tape on the concrete before it starts showing below the siding. I am not sure if that is enough to be reliable. I believe I also need to use a primer with most tapes available.
In my head, liquid flash seams like it would deal with the small overlap better. Henry Air-bloc LF seems to be the best value in this category.
I think if I do attempt to seal the sheathing to the foundation, it likely makes sense to remove the starting strip. It is a little tricky to remove cleanly as the 2" nails have rusted and are sunk into the pressure treated sill plate. There is 10 years worth of spider remains under that starter strip.
So what does everyone think, should I go ahead and seal the sheathing to the foundation?