Treated Lumber Question

[Boca]

How long do the chemicals (and therefore the hazards) remain in pressure treated lumber that was treated with arsenic and chromium? Does this wood remain forever poisoned or do the chemicals lessen or leach out of the wood over time?

 

[nealtw]

CCA is not the normal treatment for wood anymore, in 2003 it changed mostly to just copper.

 

[slownsteady]

Interesting question. Hope this helps, but note that the article is dated 2009:
http://www.straightdope.com/columns/read/2889/is-the-arsenic-in-treated-wood-dangerous

 

[nealtw]

I have built a few raised garden beds, I have lined the top 12" with 6 mil poly and the top coarse is raw cedar.

 

[Snoonyb]

How long do the chemicals (and therefore the hazards) remain in pressure treated lumber that was treated with arsenic and chromium? Does this wood remain forever poisoned or do the chemicals lessen or leach out of the wood over time?

Not long enough to curb or affect the rate of infestation prevalent in florida.

As with the inherent natural resistance which exist in species of wood, it dissipates over time.

 

[slownsteady]

Does this wood remain forever poisoned or do the chemicals lessen or leach out of the wood over time?

I imagine the key to this question is "where does this stuff go?"

 

[rokosz]

yup, right back into the ground, or your lawn, or your veggies. Remember too: there are different grades of PT: that rated for ground contact and that not. I haven't checked but I'd bet the ground stuff is good and saturated.
Lifespan: greatly effected by whether cut-ends are protected. Ever seen old rotted PT -- it usually rots from the middle out -- becaues the manu process pushes the chems _in_ and doesn't get the chems into 100% of the wood. (Maybe there's a grade of PT now that _does_ do 100% -- be nice esp. for 6x6s).

 

[nealtw]

yup, right back into the ground, or your lawn, or your veggies. Remember too: there are different grades of PT: that rated for ground contact and that not. I haven't checked but I'd bet the ground stuff is good and saturated.
Lifespan: greatly effected by whether cut-ends are protected. Ever seen old rotted PT -- it usually rots from the middle out -- becaues the manu process pushes the chems _in_ and doesn't get the chems into 100% of the wood. (Maybe there's a grade of PT now that _does_ do 100% -- be nice esp. for 6x6s).

It might penetrate if the wood was dry before the treatment but that isn't the case.

 

[Jimsox]

What do you think of this fence wood was this way at 6 months and worse now at 1.5 yrs

 

[Jimsox]

Bad wood for 1 yr old?

 

[Snoonyb]

It's aging treated lumber, enjoy the aesthetics.

 

[Jimsox]

No way for 1000’ of this mess

 

[Jimsox]

@ $9.00 a linear ft

 

[Jimsox]

Falling apart contracting and expanding every time it rains......as much as 2”

 

[nealtw]

It looks like wood that is a year out in the weather. I think the knot were there when it was new.

 

[Jimsox]

But it’s coming off the post gate latched fell off... contracting and expanding

 

[nealtw]

Now that is not nice.