Is the NEW Treated Wood any good?

Hmmm, Very interesting. You do favor eliminating toxic chemicals and yet buy that lumber treated with arsenic. I never knew arsenic is not toxic, LOL! I built a cabin on a newly treated wood pile, after 10 years it still stands. Whatever that green stuff is injected into wood.

According to :

CCA lumber (the old stuff) came in various grades. I think three that can be termed "regular" (above ground), "ground contact" (eg: sills and posts) and "marine" (full immersion). These were based on testing the material for deterioration, and production is done by tables of pressure/concentration/duration etc.

The stuff you'd normally buy would be "regular".

The "new stuff", like ACQ, has to pass the same durability tests.

As I've heard, ACQ lumber fully meets the "regular" durability standards, but isn't generally available (if at all) in ground contact or marine grades.

You will find that the new stuff is just as good as the old stuff for above ground work. It's primary drawback is that it eats fasteners, and you have to use high end galvanized or stainless.

Don't judge by the color. The strong green you saw on CCA didn't mean high quality. In fact, it meant the exact opposite - poorly controlled production.

Arsenic, per se, is not toxic - it's the concentration that counts.

Arsenic just becomes toxic at a lower concentration than, say, Kellogg's Frosted Flakes.

Thats why you have to look for the "ground contact" rating. I can't believe they sell pressure treated landscaping timbers that are not rated for ground contact. Yet people buy em (pressure treated is pressure treated, right?) thinking they are getting a bargain and they rot out in 5 years (the timbers, not the people).

The local big box store had timbers on sale (rated for ground contact in the ad). WHen I got to the store I could not find a single sale timber that had the ground contact rating printed on it. YEt the more expensive timber (next pile over) had the ground contact rating on every timber. I bypassed the sale.

This goes both for the old arsenixc ones and the AC-3 ones.

It appears that you have a misconception about treated wood. Treated wood does Not prevent it from rotting. Its purpose is to prevent termite and other bug infestation - has noting to do with preservative. Bob-tx

According to Bob :

Actually both. The formulations are designed to be toxic to both insects and rot fungi/molds. CCA had copper (first C) to kill fungi (copper is specific to invertibrates and plants), and arsenic (the A) to kill or at least discourage insects. The second C (chromium) keeps it together, and isn't terribly nice either.

Yeah, I had thought maybe previous poster would find some more about treated wood properties of interest, too...

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snipped-for-privacy@usa.com wrote in news: snipped-for-privacy@4ax.com:

The lowdown:

The New Pressure-Treated Wood The EPA is banning CCA lumber. The replacements are safer, but they may change how you build a deck.