December 14, 2000
with James Juczak
I first learned about Jim in a paper that he wrote for the CoCoCo/99 Papers. (CoCoCo stands for Continental Cordwood Conference.) Jim's paper discussed various experiments and ideas for cordwood structures. I was amazed to read about all of the "treasures" that he was able to procure for building his cordwood house without hurting the pocket book.
Included in his paper was a paragraph that discussed the merits of using paper product as the main constituent in a mortar mix. Although it was intriguing, I put the article aside and forgot about it.
Six months later I was attending the Midwest Renewable Energy Fair and stopped by Rob Roy's booth to say hi to Rob and Jaki. At his booth, Rob showed me a sample of paper based mortar that Jim had created. I was amazed by how light and strong it was. It was at this time that I became hooked on the idea of using papercrete as a mortar for cordwood walls.
Shortly thereafter I wrote about papercrete in the journal. (Click here if you would like to see the article.) The article highlighted Paul Reavis's cordwood barn and mentioned Jim's cordwood project. Since then, Jim has made quite a bit of progress on his house and the following Q & A discusses Jim's work with papercrete mortar. Please keep in mind that papercrete mortar is experimental and has only been tried by Jim Juczak, Paul Reavis and a handful of others. With that said. I personally feel that there is a bright future for papercrete mortar.
Q. Can you describe the type of house that you are presently building and how far along in the process are you?
A. We spent years dreaming about what we would like to build. The future homestead is 18 sided; it uses a post and beam frame created from beams recycled from a bowling alley that was being torn down within 5 miles of the construction site. It has two stories, will be earth roofed, masonry stove heated, off the grid, and almost 3,000 square feet. We've finished about 70% of the cordwood exterior. The exterior is cordwood and a material called papercrete.
We're building in a mined out gravel pit and hope to be living there before the end of summer 2002. By the way, NO MORTGAGE! Our goal is to have about 80% of the structure build from salvaged/recycled/indigenous materials.
you are considering building anything substantial out of cordwood TAKE ONE
OF ROB ROY'S CORDWOOD SEMINARS!! The class will dispel any doubt that this
is a very workable technique.
Not that I followed Rob's instructions to the letter; the use of papercrete, a mixture of paper pulp and some kind of cement as a binder is a departure from the norm. I wanted a mortar that was fully insulative and didn't need as much fussing to put in place as the Mortar-Insulation-Mortar technique. I also wanted a material that moved with the wood and allowed for a minimum of shrinkage and cracking.
Q. I understand that you have been using a form of papercrete as your mortar. Can you describe the composition of the mortar that you have been using to build your cordwood home?
A. After numerous experiments we found that two mixes worked very well. The first is made of site pulped newspaper, water and type "N" masonry cement. Pulping the newspapers took, in my mind, way too long. The second formula is made of industrial paper sludge, water and masonry cement. Paper sludge is paper pulp that is filtered out of the production because it is too coarse or they are finishing a run of paper and need to clean the machines out to run a batch of paper that is of a different formula. Anyway, the company I get my sludge from is within 6 miles of the site and they send about 40 cubic yards of the stuff to the landfill every day! I had to get permission from the DEC to shovel the stuff from the dumpster into my truck and then use it on my property.
material resulting from either of the mixes is as easy to use as paper mache.
Q. What type of paper are you using and what sources might someone seek for paper sources?
The newspaper came from my town's recycling center, and the sludge by calling
several mills in the area. There's unbelievable quantities of paper available
just for the asking; print shops, schools and office buildings all separate
and bale all kinds of paper products. If I were to continue to use the newspaper
I'd build a "Tow Behind Papercrete Mixer"; you can get information
on this by looking up papercrete on the Internet or by contacting Taylor Publishing
for their book/video catalog.
Q. Will regular newspaper work or other recycled paper products?
I found that regular newspaper pulped more quickly than color inserts and
magazines. I soaked the paper in barrels overnight, tore it into fist sized
pieces and threw it into a half 55 gallon drum with additional water and pulped
it with a spackle mixer attached to a 1/2" drill. You have to drain the
excess water away to mix it. I have to add a bit of water to the "dewatered
sludge" to get it to mix to the right consistency.
Q. What kind of tests have you done with the mortar and how long has the mortar used in your walls been weathering? Any signs of deterioration?
We've tried to burn it with an oxy-acetylene torch at the CoCoCo
and it glowed "like space shuttle tile", not burning at all. Anything less than about 20% cement by volume will smolder slowly if broken up a bit, then lit.
left samples out in the weather for over 3 years with little sign of deterioration,
it seems to soak up water easily though. I may wind up waterproofing the bottom
3 feet or so of my cordwood wall if this becomes a problem.
Q. By using paper in your mortar versus sand for example, the thermal mass would be less. Do you have any concerns regarding thermal mass?
Not really; the masonry cement adds a bit of mass; over 200 bags at 80# each
for my home. The 5,000 pieces of red pine, 16" long add quite a bit more.
Finally, my central tower is made of mis-cut "manhole material"(
5,000# mix, 6' diameter by 23' tall, all for $500 including delivery and setup)which
when set up as a masonry stove and filled with sand will weigh over 30 tons.
Q. Have you experienced any cracks similar to those found with "traditional" mortared cordwood walls?
No cracks and no shrinkage in either the newspaper mix or the sludge mix.
I suspect that coefficients of expansion and moisture absorbency/drying rates
are real close between the wood and the cellulose based mortar.
Q. Would you mind sharing with us your "recipe" for the mortar? I'm sure there are quite a few of us who would like to experiment with this form of mortar.
Sure! I fill a 5 gallon plastic pail about 2/3 full of paper sludge, add up
to a gallon of water depending upon the amount of water in the sludge initially
and then add 2- #10 cans of type "N" masonry cement. The mixing
is done with the spackle mixer and 1/2" drill with a pumping motion for
about 2 minutes. We mix up to 100 gallons at a time and this is good for about
1 1/2 hours work for 2 1/2 - 3 people, including rough pointing. Finish pointing
is done with a bent butter knife and stiff sponge, this adds an hour or so
for one person for each 100 gallon batch.
Q. Are there any pro's or con's to using this form of mortar?
A. Cons: The stuff takes forever to dry, several weeks at least (that may also be why it doesn't crack), it can get a bit of mold and/or mildew that has to be wiped off after the product dries completely- I may include a fungicide in my final batches.
Pros: It's very easy to work with, points easily with a sponge, cleans up well, and utilizes a material that would normally be buried at a landfill.
Q. Is there anything else you would like to add regarding these questions or express to our readers?
A. I used frames for the doors and windows that simplified and sped up the process a lot. I ran the frames up from the concrete ring beam and second floor sill. This allowed me to square up and stabilize them before the cordwood went in. The frames also gave us a 'goal' for each day, to fill between so many frames so high. It is much easier than floating the frames in the masonry and then building up the cordwood next to them to lock them in place.
You're welcome to e-mail me for more information or a sample of papercrete: firstname.lastname@example.org. We're finishing the earth roof this coming Memorial Weekend....anyone is welcome to come and lend a hand.
Thanks for your interest...-Jim-