Designing a PT Lumber Structure??

I'd like to design & build a structure from common Home Depot pressure- treated 4X4s and 2X8s, etc. It'll be a horizontally loaded vertical mast, a cantilever beam which will be out in Pennsylvania weather. My problem is that I can't find any information on design stresses for pressure-treated lumber.

First I don't even know what species wood (suger pine?) they use for PT lumber and second I can't find any information on the effects pressure-treating lumber has on it's mechanical properties. If any. The Web is full of the usual collections of handbook design data on the mechanical properties of the various species of dry, non-pressure- treated lumber under lab conditions.

The little birdie in my head is telling me not to just blindly use use those numbers else I might suffer some unpleasant results. Can anybody around here with knowledge in this field give me some pointers . . ?

Thank you.

Brian Kelly

Reply to
kelly
Loading thread data ...

In PA, wouldn't you end up with a lot of #2 (or, ouch, #3) hemfir? I don't recall ever getting a #1 in 2x's.

Reply to
Richard F.L.R.Snashall

Try

formatting link
on either "front.pdf" or "index.pdf"

Reply to
ms

This is a standard reference for the mechanical properties of woods - hard and soft - from Forest Products Lab.

formatting link
There is so much variability in wood members that a reasonable design factor ought to sweep in any reasonable pressure treatment for wood designs.

Brian Whatcott Altus OK

Reply to
Brian Whatcott

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.