Older solid brick building insulation
Hi,
I’m currently remodeling my kitchen which has one 2-wythe outside wall(about 18 feet long, 8 feet high). This is in Boston area. The wall previously haphazrdly covered(maybe 7-10 years ago) with some 1″ foil backed fiberglass stuff, but it doesn’t look like it caused any damage.
I have thoroughly studied building science corp materials, NPS preservation briefs and other materials on the subject of insulating older masonry walls. Sprayed foam is not an option, so it leaves me with two possibilities:
1) XPS panels glued to the wall, then a layer of sheetrock over metal studs. Since the room above is not being remodeled, it won’t receive any insulation at this time. So no matter how well i fill all the haps, an unknown amount of interior air might leak from the top. Or is this not a concern since the air will just rise?
Another concern is that the wall is somewhat irregular and the foam panels will not be 100% flush with the wall.
2) Leave the wall as is – without any insulation and focus on air sealing. I’m really leaning toward this solution as I really don’t want to cause any damage to already old masonry. So in this case I will just build a metal stud wall in front o the brick wall and cover it with sheetrock. Does that sound reasonable?
I will apreciate and comments/feedbacks on my ideas.
Thank you
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Replies
John,
As long as you have evaluated all of the factors that limit insulating an older brick wall -- the amount of rain that hits the wall, the quality of the bricks, and your climate -- then the best way to proceed is with closed-cell spray polyurethane foam.
For more information, see Insulating Old Brick Buildings.
Spray foam is really not an option here...
John, good to hear you want to stay away from sprayfoam (see reasons that we at 475 give for foam free construction in our Foam fails series).
The good thing is there are other approached. Of course Martin is right that the brick should remain dry (either protected or build out of low-absorptive brick) - in that case we can add interior inslation. We recommend fibrous insulation, and ideally cellulose in this case. This insulatino is then protected by smart vapor retarder (INTELLO Plus) - which keeps it dry in winter - but letting it dry inwards in summer if needed. More info about this approach can be found in the 475 blogpost that describes this approach - The possibilities (and dangers) of interior insulation of masonry buildings. We also have details and growing list of successful renovation projects , including this Passive House project in this JLC article and other case studies available at the 475 website. You can also get Pro Clima INTELLO smart vapor retarder and TESCON tapes on the 475 website, which will enable you to successfully airseal and insulate historic masonry buildings.