Papercrete is a fairly new ingredient in the natural building world. It is basically re-pulped paper fiber with portland cement or clay and/or other dirt added. When cement is added, this material is not as "green" as would be ideal, but the relatively small amount of cement is perhaps a reasonable tradeoff for what papercrete can offer. I have had a fair amount of experience with this stuff, and I would say that is has some remarkable properties. Care must be taken to utilize it properly, or you could be courting disaster. I am acquainted with both Eric Patterson and Mike McCain, who independently "invented" papercrete (they called it "padobe" and "fibrous cement") and they have both contributed considerably to the machinery to make it and the ways of using it for building.

The paper to be used can come from a variety of sources and is usually free. I've used newspaper, junk mail, magazines, books, etc., which I get from our local dump or from the waste bin at our post office. Depending on the type of mixer that is used to make pulp out of it, the paper might be soaked in water beforehand or not. My first mixer used a small electric motor mounted directly to a shaft with a couple of four inch square blades on it, rather like a milk shake maker. This shaft was suspended in a plastic 55 gallon drum where the mixing took place. After a year of making small batches with this, I graduated to a "tow mixer" designed by Mike McCain. I consider this to be the Cadillac of mixers because using it is so easy and fast.

It is basically a trailer made from the rear end of a car, with the part that would attach to the drive shaft sticking upward and a lawn mower blade attached to it. The blade is surrounded by a large stock watering tank where the mixing occurs. There is a baffle on the side of the tank to force the slurry back into the blade as it circulates. With this mixer (which I tow behind my Volvo station wagon) I can make three or four wheel barrows full of thick papercrete in about twenty minutes. I simply fill the tank nearly full of water, add about one wheel barrow full of dry paper, one sack of portland cement, and perhaps some sand, depending on how I plan to use the mix. Then I drive slowly around the block, back over a drain box with 1/8 inch mesh on the bottom, and dump the slurry into the box via a drain hole in the bottom of the tank. After about a half hour of draining the excess water from the slurry, the papercrete is like soft, workable clay, but not nearly as messy. This is the material that I used to plaster both the inside and outside of my earthbag house.





The Truth About Papercrete



with Kelly Hart

Why use papercrete
The ratio of materials
Forming and Curing
Structural issues
Papercrete as plaster
Moisture issues
Ground contact


The slurry can just as easily be pumped or dumped into forms to set up that way. Eric Patterson makes adobe brick sized blocks of papercrete to build with, and mortars them together with a slurry of the same stuff. Mike McCain prefers to either pump the slurry into slip forms or make larger blocks for building. The addition of mineral material (sand, adobe, etc.) has the advantage of minimizing the shrinkage as it cures, making the final product more durable and fire proof, at the expense of slightly less insulating value and more weight.

Cured papercrete acts like a sponge unless it is coated with something to stop the entry of water. In my earthbag/papercrete house I have allowed the papercrete to breath fully, so that it absorbs an enormous amount of water when it rains. This is not a problem for me because there is nothing in the wall that would be damaged by water, even if it got past the papercrete layer, which it rarely or never does. It is a whole new concept for a roof: a sponge that welcomes the moisture, and then simply give it back to the atmosphere through evaporation. I have had large cracks (up to about 1/2 inch wide) in the initial layer of papercrete on the earthbags, and still have not seen any water getting through into the house.

Other properties of papercrete are:
1) It is dimensionally very stable both through the process of taking in moisture and drying out and in a wide range of temperatures.
2) It will hold fasteners to some extent, especially screws, without cracking.
3) It is highly insulating (about R-2 1/2 per inch).
4) It does not support flames, but will smolder for days if it does catch fire. The more cement and mineral material that is added to the mix, the more fire proof it becomes.
5) It will support molds if it remains warm and moist for too long.
6) It will wick moisture from the ground into the wall if it buried in dirt.
7) It becomes soft and will deteriorate if kept damp (especially underground) for too long.
8) It resists rodent and insect infestation.

Paper adobe is similar to papercrete, but instead of cement used to bind the paper fiber into a solid, clay is used as the binder. This can work well if the material is kept absolutely dry; otherwise it will become soft and could deform.


Click on image to buy from Customflix.com

Building with Bags: How We Made Our Experimental Earthbag/Papercrete House 1 1/2 hr. DVD produced by Kelly Hart.We wanted to build an environmentally sensitive and aesthetically pleasing home at a moderate price. We chose to create earthbag domes covered with papercrete (recycled paper combined with cement and sand). This honest DVD documents details of the construction, insights gained, and the ups and downs (literally!) of the building process. Several other earthbag homes are also shown. For more information about the house see Photogallery & Description of Our House or Construction Details of Our House . To view a streaming video intoduction to this DVD click here.



Click on image for more information
The Making of Papercrete with Judith Williams DVD Learn how to make papercrete, a super strong and light weight alternative building material. Judith Williams demonstrates how to make papercrete in a tow mixer using recycled paper and a small amount of Portland cement. Papercrete is easy to make, inexpensive, uses recycled material, has a high R value, is easy to work with, has no harmful chemicals or outgassing and results in a comfortable and nurturing abode. Fully cured papercrete can be cut and sculpted with a reciprocating saw. This DVD explains how the mixer was made, how to mix the papercrete and how to form it into walls. Also included is a flame test where a torch was held one inch for the surface of a papercrete block for 5 minutes. Judith proves that you don't have to be young, muscle bound or wealthy to build your own unique, low cost, creative and well insulated dwelling.


Carriage House Kelly Hart, Designer

This Carriage House was initially designed to create garage and shop space, as well as office and storage space for the designer's personal use. There is potentially about 900 s.f. of usable floor area on two stories. It is a hybrid design, utilizing earthbags plastered with papercrete, a steel prefabricated Quonset-style vault, concrete floor, and wood-framed end walls. Since the steel vault is completely covered with insulating earthbags, the building is very well insulated, and comfortable year-round. This concept could be converted to residential use, with the addition of kitchen and bathroom functions, and the steel interior finish could be covered with scored sheetrock, tongue & grooved wood, or even cloth. This is rather inexpensive way to create substantial shelter. This design is based on a fairly small (16' X 34') steel building, but these structures are available in a wide range of widths ( up to sizes fit for aircraft hangers), and the lengths can be indefinite, since it is just a matter of adding more arched sections to lengthen the building.

This cross section shows the hybrid nature of this design. In order to gain height, the steel shell is erected on top of an earthbag stem wall, and then the earthbags continue on up over the building. The double columns of the stem wall provides thermal mass on the inside and insulation on the outside. An insulated concrete pad is poured for the shop/garage floor. The second floor joists and tie beams are essential elements of the design, since they resist deformation of the vault from all of the weight on it.

For more information about this plan, and many others, visit our sister site www.dreamgreenhomes.com, where you will find a wide range of plans for sustainable homes, greenhouses, small buildings, garages, and food storage space for sale. Dream Green Homes is a consortium of outstanding architects and designers, who have pooled their talent and expertise for your benefit.


livinginpaper.com I heartily recommend this site compiled by video producer Barry Fuller; it outlines in great detail his research and thought about papercrete as a building material.

makepapercrete.com some good basic nformation about papercrete and how to make it and a tow mixer.

papercreters.blogspot.com is a blog devoted to all things papercrete.

evesgarden.org Eve's Garden Organic B&B and Ecology Resource Center has done some wonderful building with papercrete and has a page about papercrete as a resource.

Starshipenterprises Several pages about papercrete, with lots of good pictures, including a look at a large papercrete dome project with lots of slow-loading pictures, but worth the wait. A papercrete list forum is operated from here.

daycreek.com Alan Stankevitz is building a cordwood house, using papercrete as morter.

Paper Observatory Domes Early approach to creating lightweight domes.

youtube.com There are several short videos posted at Youtube on papercrete.

hybridadobe.com Philip Mirkin's site explains how he makes "hybrid adobe," a mix of papercrete and soil.

MasonGreenstar.com This Texas company is gearing up to manufacture commercial "blox" of papercrete.

groups.yahoo.com is a forum devoted to discussing papercrete.

mortarsprayer.com has a page about papercrete with several embedded videos and a photogallery. 

Disclaimer Of Liability And Warranty
I specifically disclaim any warranty, either expressed or implied, concerning the information on these pages. Neither I nor any of the advisor/consultants associated with this site will have liability for loss, damage, or injury, resulting from the use of any information found on this, or any other page at this site. Kelly Hart, Hartworks, Inc.


Home       Site Map        STORE

For Email contact go to About Us
Established in 2001, GreenHomeBuilding.com is primarily a labor of love. Kelly, and the GreenHomeBuilding team of experts, have answered thousands of questions for readers over the years, and we continue to publish up-to-date information about increasingly important sustainable architecture. If you feel moved to assist us in this work, your kind donation would be much appreciated; this can be easily done through our PayPal account:
Custom Search


  [Solar Car]      [Earthbag Building]     [Dream Green Homes]
See Your Ad
in This Space!

Click Here
for More Information