There is a lot of debate about whether to put a vapour retarder (vapour barrier) on an insulated wall behind shower tiles. The code has not historically been specifically clear on this so we get lots of different interpretations. What the code does say clearly is that we should not have two vap...
Ed writes from Ajax, Ontario : All 3 walls of my bathroom shower stall are finished with 4" ceramic tiles and are in good shape. When I had to remove one of them, I discovered that the drywall was behind it was so wet that I had to put a fan on it over night to dry it out before I could glue...
Canada Mortgage and Housing Corporation (CMHC) does not recommend the use of any blown-in insulating material inside "enclosed vertical cavities" (that's a fancy way of saying "walls that are not open"). They feel that techniques of installation and verification during installation are not good ...
Joe from Beaverton, Ontario has discovered that he has rot in his floor joists. All the black wood you see in this photo is rotting wood that Joe discovered when he pulled out the existing fiberglass. In places he can poke a knife two inches into the floor joists!He has a crawl space with a ...
Dry rot is actually a fungal growth that destroys the cell structure of wood. In order to grow it requires moisture, oxygen, and warmth. Once started it will not grow in the winter, but it will survive and continue to grow during whatever periods of time provide its three necessary conditio...
Wood in contact with slightly humid concrete can easily develop dry rot. (search keyword "rot" for the title "WHAT IS DRY ROT?") This often happens to studs laid on the basement floor or standing up against basement walls. A perfectly dry basement will present no problem -- but how many ba...
A viewer in Edmonton sent us some pretty nasty photos of mould under her sink. Two plumbers told her that the moisture was not coming from the plumbing.I saw two things on her photos. First, mould was building up around the cold water pipe, meaning that there was humidity under the sink that...
Concrete will allow water or water vapour to move through it quite easily, so any wood in contact with concrete must either be pressure treated wood, or you should have a plastic separator between the wood and the concrete. A simple slip of polyethylene plastic is all it takes to prevent rot at t...
