Old house, wet brick
The picture pretty much says it all. We had terrible ice damming this year, as did just about everyone in my area; houses both old and new saw wet walls and rainy windows for the first time ever. My house was built in 1850, and I have to imagine this has been a problem before. But this was our first full winter here. I’ll try to explain the situation as best I can:
The house is balloon framed. All exterior walls finished on interior w/ plaster and in some cases plaster and drywall. Someone filled the walls with cellulose at some point in the house’s history. I assume they did so from the attic where there is a space between the wall framing and the exterior brick. It’s tough to get in there because the pitch so low and the eaves are what they are. There is about 10 in. of cellulose in the attic.
I had water coming in all of the exterior windows on both sides of the house this winter. At one point I went into the attic to find that in many places the attic insulation had piled up near the eaves and was touching the roof deck. I smoothed it out in those areas thinking I’d be allowing cool air to touch the roof deck as it was supposed to, thinking I’d help matters. I don’t think it made a difference because the attic isn’t vented properly at all. And anyway, nothing changed after I did that.
My main concern right now is that all the ice that had built up in the eaves over the winter has found its way into the wall cavities as is displayed by the wet brick. I dont’ see any signs of moisture on the plaster / drywall inside – only the wet brick. There hasn’t been snow on the roof in nearly a month. I’m positive there isn’t a leak causing this problem. It’s happening on both sides of the house. The roof is standing seam metal in good condition.
Do I leave the wet brick alone and hope the summer dries everything, including what’s likely mucky cellulose in the walls?
Do I drill weep holes in the mortar joints?
Do I rip away the plaster inside, pull the cellulose, and let the brick dry?
Any other ideas?
Thanks in advance,
Chris
as an aside, I’m thinking of blocking the eaves off and spraying the roofdeck with open cell foam. I’ve thought about venting the eaves and adding gable vents, but then I would have to dig up all the cellulose and search for all ceiling penetrations in second floor to seal them. The spray foam seems a more realistic option.
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Replies
Chris,
This isn't a pretty picture.
First, about finding out what is going on in your walls: I would open up the plaster and drywall on the interior where the bricks look wet. Cut some 8"x8" inspection holes and find out what's going on.
Second, about addressing your ice dams: By far the best way to address ice dams in a house like this -- one with difficult attic access, questionable venting, and not enough space near the eaves in the attic for adequate insulation -- is to add a thick layer of rigid foam above your roof sheathing, followed by ventilation channels above the foam, followed by new roofing. That is Step 1 toward the job of creating a conditioned attic.
It's too bad that the contractor who installed your standing-seam roofing didn't know as much as you do now.
To do the work I describe on a roof with a standing-seam metal roof in good condition is expensive and painful. But it would solve your problem.
If you don't fix this problem the best way, you will probably want to address it the second-best way: by removing the damp insulation near the eaves in your attic, and getting a spray foam contractor who knows what he's doing to install a lot of closed-cell spray foam.
But really, you need to find out how wet your walls are before you install any spray foam.
Chris,
A few more thoughts -- not particularly encouraging thoughts.
The previous owners made a few mistakes. In addition to the problem of failing to install rigid foam under that beautiful new roofing, they used the wrong type of insulation in the walls.
For more information in insulating your walls, see Insulating Old Brick Buildings.
For more information on ice dams, see these two articles:
Prevent Ice Dams With Air Sealing and Insulation
Ice Dam Basics
Martin,
Thanks very much for the thoughtful response. I'm reluctant to open up the walls inside, but I have pulled the trim off of some windows on the other side fo the house from this picture. Above the window, where the stone lintel is, I found some loosely placed fiberglass and some very wet wood. I thought that having the casing off would allow enough air in to help dry out the wall but the brick is still wet. I was assuming that the brick is wet because it's wicking water away from the cellulose. I figured (naively hoped) that eventually the moisture would escape via the brick. I guess to your point, though, the wood framing will take a lot longer to dry out this way (if ever). I'm positive there's a lot of water in the cavity because I saw it all frozen inside the eaves before the warmer weather.
I read the article on Insulating Old Brick Buildings. Thanks for the link. I know Straube has reservations about cellulose in this situation. But mine is a big variation from the multi-wythe walls described in the article. I believe the house to be balloon framed which means I have long runs of wall cavity (there is not rim joist; the foundation was carried between floor joists up to bottom of floor decking). The brick may be double wythe , or it's just a veneer. I haven't explored that far yet; I'm basing my guess on what I can see of the stone lintel and surmising its thickness based on the exterior reveal.
As for insulating the attic... The roof is by no means new. It's quite old, actually. And I understand the best-case scenario you described. But it's unrealistic for me as you said - the cost would be astronomical. I'd have to get an architect involved in order to properly maintain the aesthetics after I add 3+ inches to the roof thickness. It'll have a ripple effect with trim, barge boards, and possibly even frieze to maintain proper proportional order. Spraying the roof deck is the most realistic approach. I'm glad you mentioned closed-cell. I always assumed open-cell was the foam of choice for roof deck / "hot roof".
Thanks again.
Chris
Chris,
You probably don't have too many options when it comes to drying out your walls -- "watchful waiting" is probably the best approach. Pray for warm, dry weather, with lots of sun and not much rain. Good luck.
Thanks, Martin. I Found a spot in a closet where I plan to cut an opening you described.