I have the correct screws for the application, but was concerned primarily about the joist hangers. I read Rat's link at Simpson strong-tie; then went and looked again at what I bought. It's marked ZMAX or whatever, and says it's hot-dipped galvanized but it doesn't appear to be much coating and that's what had me concerned to start with. At any rate it should be dry as soon as the treated 2x4/s dry. I had to build a knee-wall about 32' long to change a 20' section of flat builtup roof to a 36' metal roof span. Used treated 2x4 for the plate against the existing roof, primarily to keep bugs out because some of the decking was waterlogged. I think it'll be OK, and I should have the roofing over it tomorrow. Thanks much for the input!