Insulation on a gutted house
Hi,
I have a 112 year old house made of a solid concrete brick exterior (8-10 inches thick) with a stucco cover. We have gutted down to the studs and exterior brick to run new electric and ductwork, etc. I wanted to make the house tighter, part of that being adding insulation to the new 3 inch interior stud walls that are being added. I’ve read a lot of blogs stating that adding insulation to “old houses” has multiple issues in regard to moisture movement, buildup in the walls, and negative effects on the exterior, what usually sound like, wood walls. Does anyone have any advice on what type of insulation, if any, would be best in this situation, should a vapor barrier be installed prior to hanging dry wall, etc
Thanks in advance
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Replies
Gneuner,
I don't know much about solid concrete bricks. I assume that the bricks are structural. Here is a link to an article that is only somewhat relevant: Insulating Old Brick Buildings.
That article discusses freeze/thaw damage to bricks. I assume that solid concrete bricks are less susceptible to freeze/thaw damage than clay bricks -- but I don't know for sure if that assumption is correct. A lot depends on the quality of the 112-year-old concrete.
To give you good advice, we would need to know your geographical location or climate zone.
My guess is that closed-cell spray foam is the safest insulation. You'll probably have some tricky areas, though, where thermal bridging can occur -- for example, where the wall assembly meets the floor assembly or foundation, and where the wall assembly meets the roof assembly or ceiling assembly.
I live in zone seven, and Baltimore city, Maryland. The concrete bricks are in good shape. There are places where the stucco is cracked from settling above the windows, but that will be fixed with this rehab job.
Gneuer,
Baltimore is actually in Climate Zone 4, not Zone 7. Here is a link to a GBA page that shows the climate zone map: Climate Zone map.
As I advised in my first answer, I think that your best bet is to use closed-cell spray foam -- and to pay attention to thermal bridging at the transitions.
Martin, that link just goes to the Q&A main page.
Trevor,
Right. And the main Q&A page includes the climate zone map. Click on the map and it gets bigger.
So it does. Never noticed that before. Thanks.