Thursday, August 29, 2013

Cardboard Fire Logs

Our home has a wonderful open fireplace.  Just cleaned by the chimneysweep earlier this Spring, it awaits the cold, dark, damp winter.  Just relocated here with less income than the last chapter of my life, I await a way to get cheap (read: free) fuel to feed this fireplace.

My first thought was to prowl the city looking for scrap pieces of wood to use as fuel for our indoor fireplace.  I had made a habit of this back in Iowa for campfire wood fuel.  My main source was the woodshop teacher at my old school who was happy to provide me with clean wood scraps for the campfire.  When I first began to look around for scrap wood, I found it quickly, but began to rethink my choices after some thought.  Years ago, I would have (and did!) happily burned any old wood I could find- fresh, rotten, painted, chemical-treated, anything.  I have since wised up to some of the dangers of burning certain chemicals.  Here, I have seen a great deal of wood in construction dumpsters and broken pallets behind loading docks.  These look identical to anything I would have found back home, and if/when we go camping and need wood for an outdoor campfire, I'll happily come-a-collecting.  I wonder about the safety of burning any construction waste indoors.

That's the key- indoors.  Anything that is in the fuel we burn in our living room is going to end up filling our living space with invisible molecules, permeating the walls -and our lungs- with whatever fun compounds are present.  Fire and chemistry do not lie, nor do they play favorites, so we have to be careful.  I think scrap wood from unknown sources will be out for now.

Never fear!  The internet is here!

I had heard of, and maybe had seen some late night infomercials advertising, ways to make firewood-like fuel out of waste paper.  After some quick searching, I found many ways to make firewood from the materials I had at hand.  Mind you, some of them required buying an expensive piece of equipment, all of which I quickly ignored.

We had a box of loose newspapers and junk mail AND a pile of empty corrugated cardboard boxes from our unpacking and setting up.  The paper products needed to soak overnight, so that post will wait for another day.  First up, the cardboard...

According to the instructions, the first step is to decide on a uniform(ish) width for all of your logs.  I made a template piece (the narrow strip on the right in the first photo) and cut all of the flattened boxes into strips of varying lengths and equal(ish) width.

Making cardboard firewood, I cut the cardboard into uniform-width pieces.
Using the template (right) I cut uniform-width pieces
 To ensure I didn't cut up the floor of the apartment, I used a piece of cardboard as a cutting surface.  Look closely, and a big slash can be seen on the cutting surface.  I'm glad it was there!

Making cardboard firewood, I used a piece of cardboard as a cutting surface to ensure I didn't cut the floor
Glad the slash was on the cardboard and not the floor!
I assembled the finished pieces (including the cutting surface piece) into a stack with the scrap pieces.

Making cardboard firewood, I assembled the finished pieces and the scraps into a pile.
Pretty good stack!
Next up was a quick soak in the tub.  This is not a thorough saturation, just enough of a dunk to get everything soft and wet.  The wet cardboard will roll more easily and will stick to itself more readily for a tighter roll.

Making cardboard firewood, I soaked the pieces in water to ease in rolling and sticking.
A quick soak in the tub
After draining the tub, it was time to assemble the final rolls.  I lined up one piece and began a tight roll from one end.  I set the next piece of the roll to overlap by 5-6 inches and continued rolling.  This was repeated, piece after piece, until the log was the desired size.  This step was difficult to photograph, requiring the constant use of both hands, so no photo this time.

The yield of three amazon boxes, a printer box, and the IKEA TV stand box was two full-size logs and one half-size log.  Set out on the window box to dry, they look like very fat cigars.  The drying time should be several weeks, so hopefully I can lay in a pretty good stock of these before the winter blows in.

Making cardboard firewood, I set them on the window box to dry.
Drying on the window box.

To make more, I'll need much more cardboard and newspaper than we will receive naturally.  Don't ask me where I will get the rest of my supply.  It's legal, but you might not care to think about it.  Maybe, after a rainy day, I can get pre-wetted cardboard, ready to roll...

Edit:  The logs, unfortunately, didn't get a chance to show their true potential here in Dublin.  I wasn't able to get them fully dry in our damp environment and north-facing window.  I did burn them when partially dry, and the outside layers behaved exactly as planned.  They burned slowly but not smokily and kicked out enough heat and flame to justify the effort of making them.  When the fire reached the not-yet-dry centers, it predictably smoldered out.

I am confident that given enough sun and dry summer air they would have dried to the center and worked great for the winter.  Sadly, I won't be making them again as long as we are in this small Dublin apartment.


  1. "cheap (read: free)" Haha, priceless. Haha, get it! I can't wait to see the follow-up burning of the stogie boards.

    1. I will post an update if I can actually get them to burn. Still a few weeks before they will be dry enough to light.

    2. I will post an update if I can actually get them to burn. Still a few weeks before they will be dry enough to light.

  2. Wow, they look great! Are they tied together with anything, or did they stay nice and tight when they dried?

    1. They did stay together, but I ended up tying them with some scrap pieces of yarn from Sara's knitting, just in case they want to unravel in the months before winter.

  3. I saw a guy on "Extreme Cheapskates" that went to the local laundry mat to get free lint for fire starter material!

  4. did they end up burning alright?

    1. Well- yes and no. In the wet climate here I was having a tough time getting them dry. Our apartment doesn't have a window with direct sunlight and the air inside the place is always humid. We didn't like keeping them inside for worry of bugs and things, so I burned them when they were only partially dry. The outside burned great with them, not as fast as loose cardboard, but not as slowly as real wood. Once the first few layers burned away, the still-damp insides smoldered pretty slowly.

      I think I'll wait to try this again someday when we live in a drier climate.

    2. do have try to roll cardboard dry? with special tool a have respectable result

  5. Try using a blow dryer to dry the logs. Be careful, of course. I'm excited to try making these logs, for the first time . I live in a cold, humid area. Great article!!

    1. I would be a bit hesitant to try the blow dryer just because of the high energy use. I'm sure it would help dry out the logs, but electricity is quite expensive here, so the power use might end up costing more than any money saved making these logs.

      If power is cheap where you live, give it a try and let me know how it works!

  6. We do this as we get loads of cardboard over the year, when they are fully dry (we have long hot summers here in Bulgaria) they burn really well and hot.

    1. Great! Glad it works for you in Bulgaria. I'm going to try it again if we ever live in a drier climate.

  7. Replies
    1. Too bad it didn't work very well. It was a fun project.


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