1899 *NOT* brick nogging – insulation questions
Edit: it ain’t brick, it’s plaster. See post #8
We pulled the drywall off the walls (and ceiling) of the living room of our 1899 farmhouse to redo some plumbing of a bath above it (ceiling) and pull out an ugly built-in (walls). House is zone 5ish, outside Toronto, Canada.
The walls are balloon framed (2 story house), with brick nogging that is covered by parging on the inside. Due to the size of the framing (maybe 6″), the parged brick nogging leaves 2.5″ to 3″ of space on the inside.I chipped off a bit of parging to check (see photos).
The previous owners (who gutted/redid the house) put in fiberglass into this 2.5″ space and plastic vapour barrier, that is of course not sealed at all, especially at the ceiling joists where it is missing.
On the outside it is 1″ horizontal board sheathing and painted vertical siding.
So, what to do with this ~2.5″? Today only tackling 1 room, and even it will be done one half at a time cause logistics. There is a bedroom and bathroom above, so we cannot just remove the brick nogging (otherwise nothing is supporting the bricks above).
1. pull out all the fiberglass and pull off the 6 mil poly as it’s probably useless and go back to how it was in 1899? Moisture may condense on brick parging in winter, but will dry off easily. Seems not great and the house isn’t that warm in winter. Airsealing is awful as noticed when it is windy in winter.
2. pull that out, and cut/cobble 2″ foam? Worried that I will not seal something and then it can’t dry out as well, though in theory it can dry to the outside. This seems like the “best option” to me, but still worry about the moisture aspect as it’s cold here in winter.
3. spray foam? 2.5″ doesn’t seem like much and likely too hard to do with closed cell due to the depth. And since we are only doing 1 room, it won’t be easy or cheap to get somebody out for such a small job (< 300 sq ft).
4. pull out fiberglass/poly, but seal masonry at cracks (hardly any, it looks great) and where it meets studs (easy to seal with caulk, gaps are 1/16″ or less). won’t make it warmer, but should seal off more drafts.
5. pull off poly and just have some vapour permeable insulation there to get some warmth. might get condensation on brick parging, but it will dry slower than #1, but in theory a bit warmer than #1. Maybe combine with sealing parging from #4?
5. or ???
I haven’t found much info for keeping nogging and trying to make it better/warmer. Most articles have the nogging as full stud depth and it is removed completely.
What would those who know more than I do and why? Thanks!
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