Papercrete and Aluminum Can Wall




Papercrete (also called fibrous cement or padobe) is a versatile building material made of recycled paper fibers, dirt or sand, and cement. It can be used in much the same way as adobe: formed into bricks, then used as mortar and stucco to finish the wall.

Can walls are a way of making non-structural walls in earthships or other ecologically-friendly buildings. Aluminum or steel cans (or sometimes glass bottles) are stacked on their sides like bricks, with concrete or mortar holding them together.

I decided to use both methods to make a small fire pit for the back yard. It's crumbled a bit since I think the fire got too hot and burned out some of the paper and making it weaker, but these construction methods would work well for any structure that isn't on fire regularly and doesn't need to fit building codes. Since this structure didn't work too well as a fire pit, I plan on using it as a planter in my garden come springtime.

Right now, there are only a few city building codes in the US that allow for the use of papercrete, but if you live in unincorporated land or are building something like a dog house, then go for it!

Step 1: Drink a Lot of Soda, or Eat a Lot of Soup

You will need a lot of cans, either steel or aluminum. Steel cans will make a slightly stronger, yet heavier wall.

You will also need dirt or sand, some cement, and a bunch of shredded paper. I got shredded paper from my home and from offices, but if you have a way of pulping or shredding paper yourself, you can use any kind of paper. I've heard that glossy magazines and ads work well, since they contain clay.

For tools, I used a five-gallon bucket, a shovel, the broken handle from a snow shovel, and my hands. For best results, you should have a power drill and a paint or plaster mixing attachment to pulp the paper, but I found that simply mixing everything together worked well (until it caught fire, that is).

You might want some gloves for working with cement, since it is quite alkaline.

Step 2: Mix Stuff in a Bucket

Depending on the type of paper and dirt you use, you will need to change the proportion of the ingredients. The sandy clay in my backyard worked well for an adobe-like mixture, but in the end I had to throw out other recipes and experiment until it came out solid.

First, fill the bucket about half full of dry, shredded paper. You can also add dryer lint, or other fibrous material like straw.

Add water until it's saturated, then mix with about four shovels full of dirt, or until the mixture comes back up to the halfway point again.

Add about one shovel full of cement, or about three soup cans.

Add enough water to make it the consistency of wet concrete and stir together until uniform.

Step 3: Masonry

No, not the secret society type, I mean brick-laying. Stack the cans like bricks to make a wall, filling in the spaces between with papercrete. I first tried using a trowel, but found that my hands worked best, especially if I used gloves to protect my skin from the abrasive and corrosive mixture.

If you plan on plastering over both sides of the wall like I did, be sure to alternate which side you put the pull tab on. The pull tabs act like the chicken wire usually used for stucco, and hold the outer layers onto the wall.

That's pretty much it. Papercrete is a pretty easy to use material and can be easily formed by hand. My mixture dried within one day and cured in about a week.

I'll add some more photos soon, since right now I'm about 80 miles from the fire pit.

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    15 Discussions

    Mark Rehorst

    10 years ago on Introduction

    I think it would be better to stick with bottles. If you use either steel or aluminum cans the concrete/water will corrode the cans quickly and you'll end up with a mass of cement rubble with corroded metal bits hanging out. It would be a real disposal problem.

    5 replies

    Aluminum cans will not corrode.  That is part of the problem with them in the environment.  Utilizing them in this way is a good way to strengthen the wall, take up space in the wall, and removing them from the environment.


    Reply 8 years ago on Introduction

    You would be astounded at how fast salt or brackish water will totally destroy an aluminum can. At first they look like black paper that is crumbling and falling apart. The vanishing point may be less than three years. I am certain that numerous, common chemicals would do a better job of disolving aluminum cans as well. Cement may well be one of those chemicals and lime mortar ought to be a real thriller. Oddly the little pull tabs on cans seem to be made of a much more resistant alloy. Those tabs can last quite a while.
    I found this out with an underwater metal detector while hunting gold jewelry. You don't even want to know how many tens of thousands of cans and tabs I have dug up.


    Reply 3 years ago

    yes, one is a 5182 alloy and one is a 3104 alloy. Body stock is indeed different from tab stock and even end stock. BUT it is worth noting that aluminum is an infinitely recyclable material. It can leave the metal producer, go to your fridge and be back again in 90 days...and repeated over & over!


    Reply 9 years ago on Introduction

    Aluminum cans can corrode and even desolve in some environments. For example in salt water tidal areas aluminum cans decompose in a year or two. There are numerous chemicals used in making concrete these days and I would not make too many assumptions about aluminum cans lasting when exposed to concrete or mortar mixes. If you know people with mobile homes you may be aware that their roofs are usually aluminum and people frequently have roof leaks from corrosion in spots on the roofs. That is one reason that mobile home owners tend to be vigilant in applying Snow White to the roofs every year or two. It keeps the roofs metal in far better condition than allowing sun and rain to contact the roof directly.

    Well, there isn't very much cement in it, and the cans have paint on the outside which should protect them. I've known a couple people who have made these kinds of walls, and they all held up well. Just don't use it for anything structural.


    6 years ago on Introduction

    There is a long track record of soda can and bottle walls, people have been using them for decades without the walls falling down. There is a difference between asking a question and declaring a project invalid when you don't have any actual experience with it. Earthships use can and bottle walls though this is the first version I have seen with papercrete. Usually it is straight cement. I might try this to build a raised planter walls this summer. If I can use up some of the piles of paper that need shredding in the process all the better!


    9 years ago on Introduction

     Unless you fill every Can, they will get water in them. When that happens it's going to be one of the most amazing mosquito breeding grounds you've ever seen. Like dozens of birdhouses for mosquitoes.

    1 reply

    10 years ago on Introduction

    Are you like me and like to burn things, or was the fire accidental?


    10 years ago on Introduction

    As an aside, that's a pretty good variety of cans you have there. Also, I have to give bonus points for use of Vernors cans!

    du fox

    10 years ago on Introduction

    at the very least they should cover the cans with more papercrete it isnt exposed and to keep the insulation properties intact. why would you put dirt in the mix? frankly your the only source ive seen that says papercrete can have anything other than paper cement and water in it. i think this more closely resembles adobecrete. you should look into ferrocement.