I talked to the structural plan checker who gave these comments. He said I would need to hire a certified grading agency to grade the wood but he doesn't think I will be able to find one that will be willing to come to my house for such a small task. He said the other option would be to cut out a piece of wood from the truss and send it to the lab for testing, which is also unpractical as that would damage the truss, and he will probably make me redo my whole roof. I asked him has anyone been able to put in a 4x4 skylight in a trussed roof system and he said many engineers have attempted a permit before but none has ever gotten a permit from him. Basically he said there's no way for it to be done without tearing out the roof and rebuilding new trusses around the skylight. If I knew this building department was this difficult, I would have never wasted 2+ months on this. I bought the house in May and I still haven't been able to start construction. I'm paying mortgage, property tax, insurance, and utility bills on the new house and still renting another place waiting for the whole permit/construction process to be over with so I can move in. My plan checker friends at all the other jurisdictions around Daly City said the work I'm doing is so simple, I would have gotten an over the counter permit. It sucks thinking that I'm paying such a hefty price for being a good law abiding citizen.