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Tony[_19_]

wrote:
On Thu, 27 May 2010 07:48:20 -0500, dpb wrote:

cubby wrote:
The last times I have used PT 4x4 posts (fence posts, supports for an
overhang, and a deck) they have warped and twisted when drying to the
point where they look a mess and where structural integrity is
compromised. It normally takes 6-12 months to dry out and twist. My
question is, is cedar any better? I'm doing another deck and am
willing to pay the extra if it will stay straight.

I often wonder whether there is a case to go back to the lumber
retailer and seek compensation for the warpage. I'm sure the answer
is no (or at best they might give you a replacement piece, which is
nothing compared to the labor to fix it) but it isn't right.

Cub
You can buy dry PT as well as the routine that is typical of the BORG.
It will be much more stable.

I've not experienced such severe problems as you describe that it has
any bearing on the structural integrity of a structure; in that case my
first reaction is it wasn't sturdily enough designed/assembled with
potential movement in mind to begin with...

Construction cedar will be dried to normal construction timber moisture
levels (higher than hardwoods, not full of treatment as is "wet" PT) so
doesn't have as much. But, while it is more resistant than some other
woods, it doesn't have the resistance of PT (altho I think the new PT
isn't near what the banned formulations used to be, either). Also,
there is some difference in the eastern and western cedars; for ground
contact I'd still recommend staying w/ PT but find dried material.

If you can't find "dry" pt, you need to shade it from direct sun until
it IS dry. When it dries much faster on one side than the other it
twists quite iolently.

I've already bought about twice as much PT as I needed and let it dry.
I used the good stuff and returned the twisted stuff to Lows.