Wednesday, August 11, 2010

What's Behind the Walls?

Ever wonder what was behind your walls? If you've ever had any remodeling work done, you know that sometimes you can be in for a surprise. Our walls have been off for a couple weeks now,  and  I did a photo expedition into the curtained off part of the house. There were some interesting findings.

The first one was this:

and it certainly came as a surprise. What you see is one of the biggest No-Nos in remodeling: a large hole cut through a load bearing header. The previous owner installed a hall half-bath, and he cut the hole to run the toilet vent through. In California, with our out-sized earthquake activity, this can lead to a major structural failure during a severe earthquake.

The result is some extra expense and time needed to fix the problem. It should be fixable by running a metal strap across the header and another strap at an angle from the header to the top of the wall. But I've not had a full structural report yet, so I don't know precisely what the structural engineer will recommend.

Here's another one, that I sort of knew would be there:

The blackish stain you see around the ridge is mold. The house originally had a shake roof, but we had it replaced with a composite roof when we moved in . According to, a composite roof with fiberglass batt insulation requires a ventilation space under the roof decking so condensation doesn't form in the winter. Our contractor told us nothing about this, and I didn't really know enough about construction  at that time to ask (I know more now, and I don't trust contractors to know anymore either). So there are areas on the roof, like this one, that have some mold on them. Not a lot of mold, but still some. The ridge is particularly bad since it is the highest point in the house, so all the hot air collected there and the water condensed out as the heat radiated out through the ridge (increasing our heating carbon footprint). We of course need to get the mold treated, so more time and expense.

Unlike fiberglass batt, closed cell foam does not let air through so it can be installed directly in contact with the roof decking. Closed cell is not only more energy efficient than fiberglass batt, but it also is much less complicated than having to install vents at intervals along the roof, like some of our neighbors have.

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