Cardboard as a fuel source?

[roadking]

I've looked online and watched some videos, read some articles, but looking for firsthand knowledge.

Regular built in fireplace (likely 70s era), chimney swept every year, we burn 2 to 3 cords of hardwood a year.

I presently, and for the forseeable future, have a limitless supply of cardboard come thru the shop that just gets thrown away. I'm talking by the pallet load.

Is there a safety issue, or other issue besides the amount of ash, in using cardboard "logs" as a supplemental fuel supply? Will it damage a masonry chimney? Create excess creosote?

Just seems wasteful to throw it out...and pay for said disposal when it seems like a decent heat supplier.

Thanks in advance.

[solargeek]

No don’t do it
Do a quick Google search saying “using cardboard in a home fireplace”.
Every one of them says don’t do it for a number of reasons.

We know firsthand that when you burn any type of cardboard or even brown thick paper, small pieces can float up into your chimney. These can ignite any creosote the smallest amount and cause a chimney fire. And If you don’t have a proper chimney grate at the top to keep out bats and insects and baby squirrels at the top of your fireplace these flaming pieces can go out and start a fire on your lawn.

Cardboard has inks that have harmful chemicals. It’s a media release into your environment when it’s burned

Here is one of the many articles
chimneysweeper.com/7-items-never-burn-fireplace/

Hope this helps.

[daw]

Cardboard is very hot! But I don't think it would be wise for indoor burning.
I know newspapers are soaked and dried to make logs but cardboard is a step removed from rich pine.

[Ozarks Tom]

I wouldn't do it, as solargeek, says the chance of chimney fire is something you just flat don't want. I had one in a chimney similar to the '60s style you mention, and if it hadn't been raining all day I'd have lost the house. Molten balls of creosote we shooting out of the chimney like roman candles. I soaked a blanket and held it in front of the fireplace to smother it out.

[farmrbrown]

Correct, not as a fuel source and definitely not in a fireplace. A good wood stove is much more efficient for heating and I have burned cardboard in mine but mainly as a fire starter and/or just to get rid of it, same as burning confidential letters, mail, newspapers, etc.
I had a short learning curve when I got my wood stove and I soon find out what were the myths and the truth. You can burn darn near anything you want as long as it doesn't produce poisonous gas and you burn it at a high enough temperature. That's the key to burning pine woods - burn it HOT and there won't be any creosote. If that weren't true, no one above 50 degrees latitude in this hemisphere could use wood to heat their homes, lol.

[paisley2]

Yep, farmrbrown, almost 100% pine here.

roadking,
You have mulch. Lay the cardboard where you want a garden.
Contact garden groups, 4H group and like groups...

[wildhorseluvr]

Jan 9, 2024 20:44:49 GMT paisley2 said:

Yep, farmrbrown , almost 100% pine here.

roadking ,
You have mulch. Lay the cardboard where you want a garden.
Contact garden groups, 4H group and like groups...

I’ve used plain cardboard in garden spaces…might have a small amount of black ink but basically plain. Per the article solargeek posted, burning cardboard is bad due to toxicity from the inks. If people use cardboard with printing on it in their garden, wouldn’t that ink eventually leach into the soil, or is it only a problem when it’s burned? solargeek, any thoughts on this?

[Jolly]

Does this mean we can't burn cut-up tires in the heater no more? 

[farmrbrown]

Jan 10, 2024 0:24:17 GMT Jolly said:

Does this mean we can't burn cut-up tires in the heater no more? 

Only do it when it's time for the in-laws to go home. 

[Jolly]

I've known folks to do it...

[sawmilljim]

I thought most all inks are soy based now days and you could drink it with no harm done ?

[wildhorseluvr]

Jan 10, 2024 15:55:46 GMT sawmilljim said:

I thought most all inks are soy based now days and you could drink it with no harm done ?

Did some searching and the general opinion seems to be that colored inks, glossy finishes, plastic coatings, etc are toxic, as are plastics, packaging info. and some tapes. 
Black ink on cardboard is generally considered safe for use in organic gardening.
The glue used to form the cardboard itself is found in plants (such as rice, what, potatoes), but the glue used to form the cardboard into boxes can contain chemicals. It was suggested that the glued edges of the cardboard boxes be cut away and discarded, and tape, plastics, etc be removed before using. 

[wildhorseluvr]

I just realized I can get an endless supply of cardboard boxes with minimal black ink and no tape, plastic, etc. Think I’ll start gathering some for use this summer. 🙂

[TxGal]

I'm really glad you asked, Roadking. I'm very guilty of burning boxes in the fireplace.

[Ozarks Tom]

I failed to mention, when I had the chimney fire I'd thrown a cardboard box with wrapping paper in the fireplace. The flames got up past the damper and into the chimney itself, which lit off the chimney fire.