uncle K wrote:
We will need to be replacing the existing 2 X 4 deck boards on several
smallish decks (6' X 12' +/-). Rain water/freezing/mold/mildew are not a
factor, as this is the warmest, sunniest place in the nation. The sun has
destroyed the original decking, and several galvanized nails (which usually
hold and outlast the wood) are "floating."

I'm a PNWer, so I'm quite familiar with how to handle this in a cool, wet
climate, but I'm still learning about the wreckage hot sunshine and low
humidity can cause. I'm not sure if pressure, or otherwise treated lumber
will gain us any advantage in this situation. Trex and the like are simply
too expensive for this application, so we're looking at wood, unless there
is a cheaper alternative in synthetic materials.

We're building stucco enclosures to replace the existing wood handrails, to
afford some privacy and upgrade the look of these decks. Sealing the deck
floors, building scuppers or drain pipe systems is not an option, so the
decks must have slats to allow for the rare occasions when it does rain
(monsoons). My thinking is that it may be more cost effective, in the long
run, to use 2 X 6, 8, or 10 material, which might last longer and be less
susceptible to warping/cracking, properly attached, of course.
....
There's nothing cheaper, certainly, and it's plenty hot and sunny here
as well (SW KS) and my experience w/ Trex, et al. is they don't handle
the UV well and they're particularly unsuited owing to the high heat
capacity (it's like walking on the hot pizza tomato paste kinda' feeling)...

I don't know what sort of life you got on the existing nor what they
used, but I'd stick w/ 6" or less width and probably just go w/ the
standard 5/4 treated decking as it's likely as cheap as untreated based
on local pricing, anyway. In desert instead of merely dry country,
maybe untreated SYP will be cheaper, that you'll have to check on locally.

It's UV that's the killer; UV-blocking penetrating stains are probably
best treatment.

$0.02, imo, etc., etc., etc., ...

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