主题: deck header
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旧 2009-09-08, 04:33 PM   #1
huangyhg
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默认 deck header

deck header
need some reassurance. i have a deck i'd like to build a roof on, making it a porch. standard construction: 5' wide, 25' long; 2x10 ledger bolted to the foundation, 4x10 header, 22 joists 2x8 x5'. the header sits right on the piers, wihtout posts. problem: the header is not perfectly plumb, it has a 6 degree tilt outwards. i worry that, because of that angle, the weight vector of the roof, loaded with chicago snow (i figure about 3000 lbs total) will have at least some small vector component outward; thereby tending the header to roll or tilt more. question is, given these numbers, just how much outward force is being placed on that header, and will 22 joists (including doubled stringers on the ends face-nailed into the header) be enough to hold it in place? and just how much of the total weight of the roof is actually sitting on the header, and how much is dispersed to the wall it's leaning on? (5/12 pitch to the porch roof)
your outward component will be small (likely less than 50 lbf). i would suggest an "l" bracket at each joist to tie the header and joists together to prevent any more roll. you might even be able to pull the existing roll out with this method.
more of your snow load will be on the drift side (nearest the wall).
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