How can I tell if old wood is pressure treated?

[Nate Nagel]

I just replaced the stair treads leading up to the deck behind my house... I used PT wood for the new ones, but the old ones (installed circa 1980, I am guessing) were so old, weathered, and in some places rotten that I can't tell if they were ever PT or not. My question is this; since I've got a whole trash barrel full of wood that I've removed from the deck, if I can chop it up for firewood I will, but obviously I wouldn't want to burn any PT wood in my wood stove.

Is there any easy way to tell, or should I just set it out for the trash man and forget about it?

thanks,

nate

[hallerb]

better safe than sorry dont burn cut into small pieces put in garbage over time

[Jack]

Crosscut the wood and look at the rings. If you see a green (or whatever color was used) ring around the wood, its pressure treated. If you don't it may or may not be.

[LayPerson Tom]

IMHO, I would never bring in wood I even thought was 'sick'. This could release pests, molds, and spores into my home.

Just a precaution....

tom @

[Mark]

I pulled out my old deck last year - it was over 20 years old and PT. I'd never treated it with anything so it was well weathered, but no rot. It was built about 15 inches off the ground and the back side of the wood was still nearly as green as the day I put it in. (Had I known that I might have pulled the deck up and turned it over years ago, but we were adding on to the house so it had to go.

If yours has been in 20 years I'd guess it was either PT, or very well sealed and maintained over the years, or you live in a pretty dry climate. Plan untreated wood, particularly pine, would probably have rotted out long ago. Cedar or Redwood might have lasted longer, but I don't think the pressure treat either of these woods.

[mm]

The country garbage people here are pretty liberal. They'll take complete bathroom cabinets, and they took my metal 4 drawer file cabinet. IOW, check with the neighbors wheter it is necessary to cut it up, or better yet, call the county (anonymously). Your neighbors might think things are prohibited that aren't. Or maybe they are prohibited but the guys on my route don't care. Only once have I seen them leave something behind -- I don't remember what it was.

Although I think construction waste is explicitly prohibited here, so a little at a time is good advice.

If you do have to cut it up, where a mask of some sort so you don't breathe the sawdust/arsenic dust.

[Bob]

If yours has been in 20 years I'd guess it was either PT, or very well sealed and maintained over the years, or you live in a pretty dry climate. Plan untreated wood, particularly pine, would probably have rotted out long ago. Cedar or Redwood might have lasted longer, but I don't think the pressure treat either of these woods.

You seem to imply that PT wood lasts longer. I was under the same impression until I read in builder's magazine that is not true.

The reason for using PT wood is to repel incects, termites etc. The treating does nothing to improve the lasting aspect.

I asked about this at the lumber yard (not HD or Lowes) and they said the same thing. Was news to me. Bob