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One thing I've learned from investigating problems with wood in residential construction is that everybody makes mistakes. Most are minor lapses that don't rise above punch list or callback status. But as the following true stories show, every once in a while I see something that makes me wonder, "What were they thinking?"

The Finishing Touch

A homeowner complains that the cedar bevel siding is falling off her house less than a year after it was installed. Turns out the builder fastened it with pneumatically-driven finish nails. The nail heads are so small that they pull through the siding as the wood shrinks and swells in thickness and tries to cup. This occurs where the nails are sunk into the framing — lots of nails missed the framing altogether. Where that happened, movement of the siding slowly rachets their smooth shank out of the plywood sheathing. The only fix is to remove the siding and properly hand-nail new siding into the framing with ring-shank stainless-steel siding nails.


Hear No Evil, See No Evil, Speak No Evil

An architect visits the house he's having built for himself and is stunned by the condition of the wood I-joists the contractor used to frame the floors. By now, the two-story building is weathertight, and pipes and wires have been roughed-in through the I-joists' webs. Amazingly, the contractor installed nearly two dozen I-joists with obviously rotted webs without blinking an eye or mentioning anything to anyone simply because that's what was delivered to the job site. Equally astonishing is the apathetic silence of the plumber, electrician, and code officials who signed off on three separate inspections. One flange of every I-joist is weathered and gray, as is one side of the web of two I-joists. Clearly, these two I-joists were on the outside of a banded bundle that got wet and rotted while being improperly stored out in the open somewhere along the way. Whether the rotted I-joists are reinforced or removed, the utilities have to be pulled.



On-Center Space-Out

A developer stops by one of the spec houses he's financing a few days after the roof is shingled. He notices that all three of the building's hip roofs have three slightly different planes instead of a single plane that rises smoothly from eaves to ridge. Turns out the builder consistently positioned the first hip truss in each roof too far from the girder truss. This happened because he incorrectly referenced his measurement for the location of the first hip truss. Instead of measuring from the outside face of the girder truss — a two-ply truss 3 inches thick — to the outside face of the first hip truss, he measured from the center of the girder truss to the outside face of the first hip truss. This put the outside face of the first hip truss 25 1/2 inches from the outside face of the girder truss instead of the 24 inches called for. Consequently, the roof angle rose at the intended 45 degrees, dove to 43 degrees, then climbed back to 45 degrees. Although each plane sticks out like a sore thumb when the sun is low in the sky, the homeowner will have to learn to live with it.