Wood deck design 97 UBC

[RobLauder223]

Is there a requirement for structural members exposed to weather (deck joists, girders and posts) to be pressure treated or naturally resistant to decay? Project is in
Lake Tahoe area.

 

[SacreBleu]

There isn't....assumption is that wood will be painted or stainbed to protect against weather. You certainly will get long-lasting snow in that area.

 

[RobLauder223]

Thanks for the quick response!

 

[OldPaperMaker]

If you are in California I understand that you are still using the 97 UBC. Section 2306.12 Weather Exposure (page 2-276) seems to say that you need "wood of natural resistance to decay or treated wood".
I had a project, in the State of Washington, where the contractor did not follow the drawings (which called for P.T. wood)and installed non pressure treated beams under an outdoor deck. When the building inspector noted the variance the owner got around the issue by saying that he would coat the structure with some Snake-oil and deal with the potential reduced life of the structure.
That's my Two-Bits worth.

 

[SacreBleu]

OldPaperMaker,
Does that section relate to wood within 18" of the ground surface?
I have done many exposed lumber structures, especially heavy timber structures. The have never been pressure-treated or naturally decay-resistant timbers. However, for 2 x lumber, I think you definitely have a point.
I have been involved hith a custom home building company that designs/builds post and beam frame type homes. They used decay-resistant wood, which makes sense because you don't want an expensive home that needs constant painting or staining.

 

[RobLauder223]

FYI, I have sent an email to Eldorado County building dept. to get their take on this question, but I know Carson City, NV has interpreted it to require p.t. or redwood. when I hear from them I'll let you know.

 

[SacreBleu]

For what it is worth, locally here in the SW USA where I do most work, many towns are under 1997 UBC, and do not require PT or decay-resistant wood for exposed decks. The annual rainfall is less than 9", and snow is short-lived. Any exposed wood posts for the deck (if not stucco-wrapped) are merely painted.
We recently did a custom home where a portion of the roof trusses are exposed and painted (that does make me nervous).