Burning plywood

[Bruce]

I have some plywood scraps that I want to dispose of. Is it okay to burn them outside or should they go to the landfill?

[reible]

Ah the good old days when you could burn things... around my area they have banned that sort of thing, you have to bundle and tag ($) so they can dispose of it properly. Or take it to a once a year collection for free...

The pieces I have that are scrap are small enough to be fire starters... I guess that is legal.

Ed

[a1gutterman]

Ah the good old days when you could burn things... around my area they have banned that sort of thing, you have to bundle and tag ($) so they can dispose of it properly. Or take it to a once a year collection for free...

The pieces I have that are scrap are small enough to be fire starters... I guess that is legal.

Ed

Where I live, you may only use "natural fuels" for outdoor fires. That DOES KNOT include building materials of any kind. Outdoor fires do knot include fires burning in appliances built for Bar-B-Q's and the like. I am knot familiar with fuel restrictions in those appliances, but I know that even when there is a burn ban, you are allowed to use those. This law/rule/whatever-it-is does knot apply to indoor fires. Indoor fires can be fueled with building materials as long as they are knot hazardous, such as treated lumber.

[hoagie]

...Indoor fires can be fueled with building materials as long as they are knot hazardous, such as treated lumber.

Years ago a chimney cleaner told me to NEVER burn plywood, MDF, OSB or any other manufactured wood product, as well as treated lumber in an indoor fireplace. The adhesives in the plywood, MDF, OSB, etc. could release toxic fumes if burned. They will also cause buildup in your chimney that will need to be cleaned out, if it doesn't cause a flue fire first.

I had no way of checking to see if this warning is accurate or not, but it made sense to me. Scraps are used in the outdoor firepit (they haven't outlawed them here yet) or when camping.

[a1gutterman]

Years ago a chimney cleaner told me to NEVER burn plywood, MDF, OSB or any other manufactured wood product, as well as treated lumber in an indoor fireplace. The adhesives in the plywood, MDF, OSB, etc. could release toxic fumes if burned. They will also cause buildup in your chimney that will need to be cleaned out, if it doesn't cause a flue fire first.

I had no way of checking to see if this warning is accurate or not, but it made sense to me. Scraps are used in the outdoor firepit (they haven't outlawed them here yet) or when camping.

Hi hoagie,
I do knot have a way to burn "inside" so I do knot have to pay attention to what exactly can knot be burned; I only know that hazardous items are prohibited. It could be that ply and those other glued products are part of that group. My local fire department told me that we are knot allowed (legally that is) to burn even dimensional, non treated lumber, such as 2X4 ends, in outdoor fires. You can burn that in indoor fires.

[Ed in Tampa]

I would be careful burning shop scraps in a fireplace. The wood is very dry compared to normal fire wood and burns with fierce intensity.

When I lived in up north I would from time to time start the fire in the fire place with scraps and that always worked fine. I usually had a cord or two of stacked/split firewood.
One time I decided to get rid of some 2x4's that had been used and reused and were filled with nail holes. I cut them to fireplace length and stacked them in the fireplace and light them.

The fire was intense far more than a equal amount of split wood that I normally burnt. At one point I had the fireplace making a wolfing sound, wolf, wolf, wolf. My buddy told me that he was outside and everytime I heard the wolf a huge puff and smoke and flame would jump from chimney. It was new house less than 3 years and the fireplace/chimney were in great shape so there was not problem but a former fireman told me that in an older house this situation could have been disasterious.

If you burn kiln dried wood use it with moderation and check on flue temperatures from time to time.

[charlese]

Let me speak for a minute about burning wood in an open fireplace. What Ed experienced with burning his 2X4s has also been experienced by burning large amounts of kindling or large amounts of paper. It's called a chimney fire.
Similar chimney fires can also occur in the flues of stoves.

These fires can take on the action of a huge blowtorch issuing from the top of a chimney. What they are caused by is a long flame, igniting the creosote that has been deposited on the flue walls.

Such fires can heat and break tile flues, can burn holes in metal flues, can crack bricks and mortar and ignite adjacent structure and cause disastrous house fires.

One way to extinguish such a fire is to close off all draft. A glass door (where you can also block built in drafts), closing all draft vents on a stove will usually work to starve the fire of oxygen. If this doesn't work, call the Fire Dept. and hold your breath (figuratively) that the fire burns itself out.

These fires are not necessarily caused by only the dryness of the fuels (wood). The dryness, of course, is only one of the factors. The major factor helping to cause a long flame and thereby igniting creosote is the surface area of the burning substance. As noted earlier, even a large amount of crumpled paper can start a chimney fire. More than several air dried (or kiln dried) boards have quite a bit more surface area than split firewood. As we have all experienced, when fresh wood surface ignites it at first produces a much longer flame than after it has been charred.

Dryness differential between cured split firewood and air dried lumber is usually around 5% to 10%. The moral and lesson here is to first start a fire, using normal kindling and lighting procedures - then feed the fire with the stuff to be burned up.

Another prevention tool, but probably the most important is to not allow creosote to build up in the flue or on the smoke shelf. Creosote removal can be accomplished by a chimney sweep and/or creosote removing logs - sold at grocery stores.

[properfection]

My folks lost their living room to a chimney fire the Christmas I was twelve. It was pretty grim as the house was heated with that old stove. Fortunately, we got extra blankets from Santa. Pop burned everything from coke (forging coal) to plywood scraps in that stove and it worked out poorly in the end. The headaches did subside after he burned the thing up though. That was the bright side.

I don't have any coal lying around today but I burn my wood scraps in a fire pit outside and away from my wood shop. I have found that much of the scrap lumber has rotted away in the wood pile over the years eliminating the need to burn it, though there does still seem to be plenty left to fuel the fire when I want to barbecue. We can still do that in Northern Colorado or, regardless, we still do.

John

[Bruce]

Okay, I never said anything about burning scraps in my fireplace, wood stove, or anywhere inside. I was only asking about burning them outside. I have one of those outdoor fire pits with a screen.

[beeg]

Well either burn em outside or send to the landfill. About the same the way I look at it, but I'd burn em.