Water infiltration through brick: Housewrap over masonry?
I have been looking all over the interwebs for an answer with no luck.
Picture this: My house foundation is rectangular shaped with a 2×2′ bump out for a masonry chimney – see sketch attached.
The exterior of the house is all brick.The green rectangle represents a typical brick wall construction (brick, air space, sheathing, insulation etc). The red rectangle is the chimney which is brick only.
Now that the fireplace is gone, I’ve discovered that water makes it through the chimney brick and eventually trickles down to the basement.
Brick is porous and since the chimney is literally just a brick wall with no other protection against water/air infiltration, I guess this is to be expected.
My plan is to cover the exterior chimney with a metallic siding, but I don’t have time now and winter is right around the corner. Planning on it for next summer.
So until then, I thought I could at least wrap the exterior of the chimney with house wrap.
I’ve been looking all over, trying to see if tyvek over brick is a good idea for this application. I was thinking of laying tyvek right over the brick and securing it with tapcons.
Thoughts?
Feel free to recommend any other temporary solutions that could last through the winter until next summer.
Thanks!
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Replies
Yac Pro,
Ordinary Tyvek deteriorates after 4 months of weather exposure. Tyvek CommercialWrap can be exposed for up to 9 months.
Your idea would work, I guess, as long as you are aware of the limitations of the housewrap, and as long as you include enough fasteners. Vertical 1x4 furring strips attached with TapCons might work better than cap fasteners.
Regular Typar is rated for 6 months; that would get you to the spring, but not summer. Typar MetroWrap is rated for 12 months.
I would suggest using Typar rather than Tyvek. It's rated for UV exposure for 180 days but I've seen it last much longer than that. A project I recently worked on had been left exposed to the elements in Ontario, Canada for 8 years with nothing but Typar over the OSB sheathing. It had deteriorated somewhat but it performed admirably considering the conditions. It's also much more difficult to tear, which is a nice feature if it's being left exposed. 5x more tear strength if you can believe the manufacturer's literature.