Burning untreated framing lumber and plywood

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frattman

New Member
Jul 29, 2013
7
connecticut
Has anyone out there had personal bad experiences with burning untreated 2x4's etc . . . on a fairly regular basis? Or even anyone that has seen someone else have negative effects to their stove? I have a new Hampton EPA insert and I'm in construction, so I have access to a lot of free scrap.

I've read that even "untreated" lumber might have been dipped in fungicide, or floated over salt water, the byproducts of burning which might corrode your stove. On the other hand I read in this Fine Homebuilding article : http://www.finehomebuilding.com/how-to/qa/dangers-of-burning-plywood.aspx

"The only studies I could find comparing combustion emissions of natural wood vs. manufactured wood showed very little difference between the two. A study by researchers at the University of Wisconsin and the U. S. Department of Agriculture Forest Products Laboratory in Madison, Wisconsin, looked at total hydrocarbons, formaldehyde, total aldehydes and carbon monoxide emissions from burning natural aspen and aspen flake board. The study simulated industrial boiler-firing conditions with high combustion temperatures (1,500° to 2,400° F) and increased air supplies."

This study references flakeboard, which is analogous to plywood, and found that if burned at the proper temperature, you can barely distinguish between the exhaust of manufactured wood and natural wood. Now, I'd never burn PT because of the arsenic and other bad stuff, but maybe some plywood isn't all that bad? And yes, I know how to avoid over-firing my stove.
 
I've never heard that untreated lumber like 2x4, 2x6 or whatever has actually been treated or could be a problem. I think the ends are painted to control the drying process but that's it. I'll wait to hear other, possibly better informed thoughts.

Plywood is out in an EPA stove. The glues and binding agents would be an issue. Far as I can tell the Wisconsin study you're referencing was done with wood fired boiler not an EPA stove. Not the same thing, AFAIK much higher temps. Even with a boiler I would not burn plywood or other treated products. Municipal incinerators that monitor temps and add air and use other processes to limit the amount and type of pollutants emitted still sometimes miss the mark so what chance do you have in a home wood fired boiler? That's just my opinion.
 
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Thanks, I think you're right about the low emissions for plywood/flakeboard being at an ideal temp and O2 mix, which I probably won't achieve - also, I wasn't sure of the burn temp on my stove. I don't think I'll chance gumming up the stove or putting (more) carcinogens in the air.
 
I was told there was no issue burning the 2x4s and 2x6s used for framing (Douglas fir), but don't use the treated stuff. I've asked 2 building supply places, a lumber yard, a guy who owns timber land in Seattle, and Home Depot. They all said exactly the same thing . . . read my first line. I'm planning on keeping the end cuts when my house is framed.
 
I have burned framing lumber for the last 25 years. - after I let it dry for about a year - And before that my father burned framing lumber all the time.
Plywood or treated - never burned and never will.
 
I'm burning 2x4 and 2x6 untreated wood right now. My cousins warehouse collapsed in on itself with all the snow and ice. I been burning it, burns quick but puts out good BTUs. It is fir. Biggest pain is trying to cut it without catching a nail but free, dry wood works great! Allows my Red Oak, Ash and Hickory cordwood dry for another year!
 
Burning plywood or osb is tempting but it just doesn't work. Small pieces of the sheet goods burn explosively for a short time due to the glues and binders added. You would have to sit there and load every few minutes.

Lumber, yes, lumber is just square cut and kiln dried firewood.
 
I get 2x4 and split them up thin for great kindling. Very hot instantly. kiln dried.:)
 
I burn DougFir, common pine, and many hardwood scraps....never do I burn plywood, adhesives and chemicals in there...
 
Ever throw a piece of particle board in a bon fire?
 
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I burn construction debris all the time. I use it as kindling and mix it in with cordwood. I've burned Doug fir, oak, maple, poplar, pine, mahogany, teak, hemlock, ipe, locust, cedar and probably others. From framing material, cabinets, furniture, trim, flooring, fence, decking, doors, pallets, siding, roofing etc. I burn tons of construction debris and love it. My favorite is oak flooring.
 
On larger industrial wood boilers untreated bare wood is treated the same as green wood. Plywood and chipboard is another story, the binders used can form furans at normal combustion temperatures. Although produced in very small volumes they bio accumulate and are quite toxic. You may be more familiar with Furans "close cousins" Dioxin What it comes down to is that burning the stuff is not recommended but there is no enforceable way of getting people to stop doing it. A good comparison is burning tires, its against the law in most areas to openly burn tires but some folks do. Tires give off a very characteristic black particulate smoke that everyone can see so your neighbors will probably apply pressure to stop which would limit most folks from doing it. Even if the neighbors didn't object someone in the town or city may object to the black plume rising from your yard. With furans, they are far more toxic than burning tires but the furans aren't visible. Just like some individuals dump used motor oil and antifreeze in the local catch basin because they don't realize or care where it goes, doesn't mean its right.
 
I have a few guys that will bring a small trailer to some of our job sights and leave it to be filled with cut offs of 2x stock. I will have the crew toss any 2x10 cut offs in my truck I like to split them small for kindling . This helps to keep the dumpster charges down and puts the wood to good use.

Also any dunage at the lumber yard gets put aside and one of us will take it home to burn. You can't beat 19% framing lumber for starting a good hot fire. But never any composite materials at all. They end up in the dumpster.
 
The only problem with framing lumber is it has no sustainability and is gone in a flash.
As a primary source of fuel, you'd be reloading all the time.

I've been framing houses for 30 years and we always have a 55 gallon drum burning during the winter.
We will frame a 6000 sq ft house and never use a dumpster until we sheath the house then the plywood scraps go in a dumpster.
We are constantly tossing scraps in there all day just to keep it going.

I have a gasification boiler and it holds temps between 1500* and 2000* all the time.
This past summer I was bringing home cribs of pallet wood from a pallet manufacture to heat my DHW.
They were mostly Southern Yellow pine with a little oak.
They were great, burned hot and fast and would bring water up to temp in a jiff but when the fall came and I tried using them for heat, they were gone before I could blink an eye.

I burned through 12 of these cribs (6 trailer loads) that's 6 cords
From May to Oct just heating water for showers and laundry.
I can't imagine trying to heat my house with it.


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Has anyone out there had personal bad experiences with burning untreated 2x4's etc . . . on a fairly regular basis? Or even anyone that has seen someone else have negative effects to their stove? I have a new Hampton EPA insert and I'm in construction, so I have access to a lot of free scrap.

I've read that even "untreated" lumber might have been dipped in fungicide, or floated over salt water, the byproducts of burning which might corrode your stove. On the other hand I read in this Fine Homebuilding article : http://www.finehomebuilding.com/how-to/qa/dangers-of-burning-plywood.aspx

"The only studies I could find comparing combustion emissions of natural wood vs. manufactured wood showed very little difference between the two. A study by researchers at the University of Wisconsin and the U. S. Department of Agriculture Forest Products Laboratory in Madison, Wisconsin, looked at total hydrocarbons, formaldehyde, total aldehydes and carbon monoxide emissions from burning natural aspen and aspen flake board. The study simulated industrial boiler-firing conditions with high combustion temperatures (1,500° to 2,400° F) and increased air supplies."

This study references flakeboard, which is analogous to plywood, and found that if burned at the proper temperature, you can barely distinguish between the exhaust of manufactured wood and natural wood. Now, I'd never burn PT because of the arsenic and other bad stuff, but maybe some plywood isn't all that bad? And yes, I know how to avoid over-firing my stove.

Welcome to the forum frattman.

After some remodeling and an addition a couple years ago we had lots of cut-offs. No problem! They really work nicely in spring and fall when you only need a quick hot fire and then let it die out. I recall burning lots of those cut-offs in the fall and still had plenty for the following spring and even used some as kindling wood.

As for the plywood; ABSOLUTELY NOT! That glue in plywood would not give you good results in the stove or chimney.
 
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