Copper Azole

[Gate2501]

I have been working on a basement finishing project in my spare time, and I quickly found myself needing more 2x4-8's. I asked a few friends who work in construction, and landed myself 25 freebies! The only problem is that they are pressure treated with this chemical, Copper Azole. After doing some research, it seems fairly harmless, especially considering it will be behind drywall for the most part, but one friend was hitting me with some serious doom and gloom about off-gassing and severe health risks, like cancer, just from having them inside a house? It seems like most of the dangerous pressure treating was done pre-2003 and involved a chemical CCA, which contained arsenic.

Would it be dangerous to use these 25 planks in my house??? I'm really quite lost.

[Singularitarian]

I have been working on a basement finishing project in my spare time, and I quickly found myself needing more 2x4-8's. I asked a few friends who work in construction, and landed myself 25 freebies! The only problem is that they are pressure treated with this chemical, Copper Azole. After doing some research, it seems fairly harmless, especially considering it will be behind drywall for the most part, but one friend was hitting me with some serious doom and gloom about off-gassing and severe health risks, like cancer, just from having them inside a house? It seems like most of the dangerous pressure treating was done pre-2003 and involved a chemical CCA, which contained arsenic.

Would it be dangerous to use these 25 planks in my house??? I'm really quite lost.

So long as it is not within physical contact, everything is ok.

[tesscaline]

You can read up about the chemical here: http://www.epa.gov/oppad001/reregistration/cca/copperazole.htm

Other than that, I don't know much about it personally. Hope the resource helps :)

[jasonpatterson]

In general treated lumber doesn't outgas to any significant extent. The purpose of the treatment is to infuse the wood with copper compounds (generally speaking) that bind to the wood fibers and prevent fungal growth and deter insects (particularly those treatments that also involve boric acid.) The treatment stays with the wood and doesn't just leak out. When you cut it, it would be wise to wash your hands before you eat and to cut it in a well ventilated place, but otherwise you're fine. The only other prohibition is burning waste scraps. That is the only easy way to free up the stuff it's been treated with, and the smoke is not friendly to you or the environment.

(This stuff is used to make picnic tables, for goodness sake. :) )

[JJM]

SkeptiChick provided a good link. My concern is whether it is meant to be used only in exterior applications. Wherever you are getting your other construction materials you can ask about that. In addition to other handling concerns, don't inhale the saw dust.

[CynicalSkeptic]

This stuff is used to make picnic tables, for goodness sake. :)

Which are generally used outside.

2x4's aren't terribly expensive. Buy the non-treated ones and do the job right.

[RoboTimbo]

Treated 2x4's are used inside all the time, particularly in basements. You have to use them when they are in contact with concrete. Non-treated will rot because concrete retains moisture and will hold it against the wood.

[davefoc]

One other caveat, from a non-expert.

I believe that the newer chemicals that replaced wood treatments that contained arsenic are highly corrosive and you are supposed to use either stainless steel fasteners or fasteners with special treatments to protect them from the corrosive effects of the chemical when you use treated wood.