Hello,
In starting to replace some water damaged siding, I was surprised to find the housewrap installed under the OSB sheathing. Is this a valid way to install housewrap? Some of the OSB is damaged and will need to be replaced but most is just fine. Should I remove all OSB and housewrap and reinstall with housewrap over the sheathing? For undamaged areas, can I leave it. Should I install housewrap on top of the sheathing (giving two layers of housewrap under and over sheathing)? Any help would be appreciated/
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>>Should I remove all OSB and housewrap and reinstall with housewrap over the sheathing?
If at all possible, I would get the wrap on top of the sheathing where it belongs. Trapping the OSB between two layers of wrap could be a problem.
Welcome to BT, first off.
(Insert standard plea to update profile by clicking on the the button near the upper right corner of the screen.)
How old is this house?
Had to be interesting (for at least the neighbors) to see house wrap go on bare studs.
Even if this was only done to an addition, that might have caught some local attention.
You mentioned water damage--have you ascertained from where that water came from to cause the damage? I ask this as it may offer a few more clues of things to look for if you have areas you are rebuilding from bare studs up.
"how old"
The house is 12 yo"where water came from"
There were two sources. First, gable has a gutter whose outflow goes into the gutter on the side and frequently is too much water at high velocity to be contained. The problem is now fixed with a proper end flashing. The siding is that awful Louisiana Pacific treated particle board. Amazingly the OSB sheathing beneath the siding is in good shape despite the siding looking like a sponge.
The second source was a rotted window sill where the OSB was rotted but studs are fine beneath housewrap. Surprisingly, the siding has held up over most of the house since it seemed to be intalled with great care (which makes the housewrap installation more mysterious). I will be replacing with fiber cement.This was not an addition so I am afraid that the whole house is this way.
This was not an addition so I am afraid that the whole house is this way.
Not many scarier words can be spoken, can there?
Can't imagine anyone who had ever been to the state shaped like a hand that would use the LP compressed fiber siding--but, I've been accused of not being imaginitive enough, too. (Mind you, about three hours' drive west of here, that siding would likely outlast the faming--but being in a 10-12" annual precipitation climate has other issues <g>.)
Hmm, now I'm thinking I might have to go wander over to buildingscience and see what they recommend for Ann Arbor's climate, as I'm drawing a complete blank.Occupational hazard of my occupation not being around (sorry Bubba)
It's not unusual to do the housewrap first, in places where it's used purely as a wind barrier and not a secondary rain shield.
If you wish it's perfectly fine to install a new layer of housewrap on the outside, either just over the repaired areas (somehow sealing the edges of the new houswrap, after lapping past the old several feet) or over the entire house. No need to remove the old stuff.