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?
Air Sealing
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
How to Prevent Condensation in Cathedral Ceiling?
Q: I’m currently dealing with insulating a cathedral ceiling, which has become a major issue. I’ve been researching solutions but feel stuck in figuring out what’s the best way to go about dealing with the problem. I have a shed roof with 2:12 pitch, built with 2x8 roof joists. It’s a mobile home that’s 14x76, so the roof is just one continuous slope. I live in northern … [Read more...] about How to Prevent Condensation in Cathedral Ceiling?
How To Install Foam Sheathing: Thickness, Vapor Barrier & Housewrap?
Q: I'm tearing the house down to bear studs inside and outside. I'm putting 1-inch rigid foam board on the outside. Do you suggest foil-faced or unfaced foam board? Where and how should I use moisture barriers in the construction of the interior walls? I live in zone 5, should I use rain screen? What do you think of cement lap board for siding? – Ron B. A: Foam … [Read more...] about How To Install Foam Sheathing: Thickness, Vapor Barrier & Housewrap?
ZIP Sheathing Vs. Plywood & Housewrap?
Q: How does the ZIP system compare to standard sheathing? It seems like 9 out of 10 new homes and remodels in my area (northern New England) are using green ZIP sheathing on the walls and some use the red version of the roof as well. How does this product compare to using plywood and a housewrap such as Tyvek? — Tom A: Zip System sheathing was introduced by Huber Engineered … [Read more...] about ZIP Sheathing Vs. Plywood & Housewrap?
Air-Sealing An Unvented Cathedral Ceiling
Q: We live in Kingston, NY and cathedral ceilinged the main living space of our 1925 raised ranch. The rafters are 2×6's. we used R-21 fiberglass batts (5 1/2 " thick) and 1" pine tongue and groove boards. The roof is an unvented shingle roof. Is there an affordable solution to prevent humidity build up? – Kate A: In cold climates, unvented roof cavities can lead to moisture … [Read more...] about Air-Sealing An Unvented Cathedral Ceiling
Is Attic Air Sealing & Insulation Worth It?
Q: Jonathan asks: We recently purchased a three-level townhome in Virginia, built about 15 years ago. The third floor, where the bedrooms are located, stays about 5º F colder than the main living area on the second level. There is only one heating zone with the thermostat on the second floor. A heating technician has balanced the ductwork, but said he cannot get more heat to … [Read more...] about Is Attic Air Sealing & Insulation Worth It?