Small snag on the deck plans. You see, we are planning to put a water tank under the deck, and the water tank needs 50" of height to fit properly (and 70" of width, which we have with no problems). We have 30" available with the current deck plans.
I've spent some time doing materials research (we're 99% likely to use Trex for the decking, with joists 12" on center to support it) and then making drawings like this:
The idea was to get the lateral bracing worked out (for earthquakes; those of you who choose to ignore the tectonic plates can skim this section). A structure can be just fine with a complete membrane in three directions, so on the right side there you'll see a small diagram of the lateral bracing running along two sides (for horizontal directions). I've still got to figure out what will work best over the horizontal (the floor plane), but I'm guessing that some sort of strapping will work fine. Trex is too floppy to make a real membrane out of the floor surface as would happen in a wood deck.
So, yeah, that 20" problem under the deck. I need to do some measuring (it may be less than 20", but not likely much less), but it looks like we're going to be in for some major digging there if we want to get a water tank (or two) under the deck. Darnit; everything else works out just fine.
posted by ayse on 06/25/07