Q: We are building a family home in Toronto, Canada using a local builder. Due to soil conditions, we had to raise our founding level. The code requires the underside of footings to be 4 ft. below grade for frost protection. In our case with a sloping grade, the footing depth is 4 inches less than the required 4 ft in some locations. The structural engineer’s opinion is … [Read more...] about Frost-Protected Shallow Foundations
Insulation
Can I Foam Basement Wall With Existing Studs?
Q: We are looking to refinish our basement in Portland OR. Because 2x4 wood studs are already installed, we can’t install foam board tight to the poured concrete foundation. Can closed cell spray foam provide effective barrier and insulation instead? Or will thinner spots behind studs limit effectiveness? - James A: It sounds like you have some space between the studs … [Read more...] about Can I Foam Basement Wall With Existing Studs?
How To Diagnose Leakage In Finished Basement?
Q: I had some moisture in my basement this winter--got onto the carpet foam and made a mess. I removed some drywall to see if there was a leak, but the only obvious issue is wetness on the vapor barrier directly behind the drywall and dampness in the drywall as well (see photo). Any ideas how to deal with this? The foundation and fiberglass insulation appear to be … [Read more...] about How To Diagnose Leakage In Finished Basement?
Combining Foam & Fiber Insulation in Cathedral Ceiling (Flash & Batt)
Q: I am renovating and old home with an uninsulated, non-vented walk up attic built in 1848. The shingle roof is less than 10 years old. The simple gable roof has 2x6 rafters. I’d like to apply 2 in. of closed-cell foam and then install 3 ½ in. of R-15 rockwool and add an Intello “smart” vapor retarder. The finished ceiling will be1/2” nickel gap shiplap. Will this approach … [Read more...] about Combining Foam & Fiber Insulation in Cathedral Ceiling (Flash & Batt)
Air-Sealing Between Chimney & Framing
Q: What’s the best way to air seal and insulate between a masonry fireplace and the surrounding wall? There is a lot of contradictory advise around about how to handle this. I will be installing a direct-vent gas insert with aluminum liners in my fireplace opening, so heat in the flue cavity will not be a big concern. The chimney material is cement block above the … [Read more...] about Air-Sealing Between Chimney & Framing
Vented Vs. Unvented Crawlspaces
Q: What are the best practices for a vented crawlspace? I bought a townhome last Nov. that has a vented crawlspace with a sump pump. There is a vapor barrier on the ground. There is a truss floor system that has faced batts that hang below the subfloor (the facing does not touch the subfloor), the rim joist was sealed with spray foam at the top and bottom and filled with … [Read more...] about Vented Vs. Unvented Crawlspaces
Preventing Mold On Bedroom Walls & Ceilings
Q: I have a damp spot in the corner of the bedroom. It is and outside wall corner. It is a bungalow so no bathroom over it. The damp spot seems to dry at times but there are tiny mold spots on it. Could it be that there is not enough circulation in the room? The window in the room becomes full of condensation when blind is down in winter so thought that may be part of … [Read more...] about Preventing Mold On Bedroom Walls & Ceilings
Insulating A Cathedral Ceiling With Foam Board
Q: What is the best way to insulate an unvented cathedral ceiling in a detached workshop? I plan to insulate before installing an AC and heating system (thinking mini-split). Is closed-cell spray foam the best, or only, good option in this case? I don't plan on finishing the space with drywall, although wouldn't rule it out in the future. .And given that it's only a workshop … [Read more...] about Insulating A Cathedral Ceiling With Foam Board