Lily Ann Fouts

Filling the Earthbags

Just to clarify, the walls of the earthbag house have been completed! However, I thought you might enjoy some video footage of the process of building the walls. In this video clip, Keith is working by himself to fill the earthbags in place on the wall. […]

Earthbag Walls – DONE!

Well, after 7 months of mixing clay slip with screenings from the nearby rock quarry and pouring the mixture into sandbags left over from Hurricane Sandy, our bag-filling days are finally over!

Yes, the earthbag walls—at least the earthbag part of them—are finished. Now we are covering them in papercrete and chicken wire and more papercrete, and will eventually (next year sometime) finish them off with lime plaster. […]

Diddling Bags for the Earthbag House

Before we fill them with the earthbag mixture, we diddle the bags so that they make a better shape for the wall and the corners don’t stick out and mess up the papercrete and lime plaster that will later cover them.

The typical way to diddle a bag is to fold in the corners and run a nail through them, securing them to the bottom of the bag. This is how we did it all last year.

However, sometimes the nails fall out or people cut or snag themselves on them, so this year Keith experimented with sewing the bags instead. He’s been very pleased with the results!

The short video below shows Keith diddling the bags with his sewing machine and explaining the procedure. If you’re building an earthbag house we recommend diddling the bags this way. Enjoy:

However, sometimes the nails fall out or people cut or snag themselves on them, so this year Keith experimented with sewing the bags instead. He’s been very pleased with the results!

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Earthbag House FAQs

Here are some questions we’ve received about our earthbag house project, and our answers to them. We’ll add more as the questions come in. Feel free to contact us and ask anything you want!

General Questions About Our Project

Q: What state are you building in?
Answer: We are building the earthbag house in Eastern Kansas—an area that can have hot/humid summers, freezing cold winters, and strong storms, including tornadoes.

Q: Why did you choose earthbags instead of straw bale/cob/adobe/earth berm, etc?
Keith’ Answer: I went with earthbag over other natural building methods for several reasons. Earthbags can use a wider range of clays and rock than adobe. Earthbag walls can also be stacked up higher over the short term rather than having to wait for them to dry as you would adobe. I would have been interested in earth berm, but our land is flat. I find this style very intriguing and perhaps I’ll be involved in this style in the future in some other location.

As for strawbale, I was strongly tempted by this natural method. The insulation is awesome and the walls go up fast Some of the downfalls are that you have to take extra care to not to let the strawbales get wet. The bales can be used to support a roof, but it a rain storm comes during the building process and they’re not covered well, you may have to start over. It’s best to put up a post beam structure, complete the roof, then stack the bales between the beams. Fires usually are not an issue once you cover the walls with a good layer of cob/plaster.

Earthbags can use a wider range of clays and rock than adobe. Earthbag walls can also be stacked up higher over the short term rather than having to wait for them to dry as you would adobe.

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If I would have gone with strawbales, I would have started with the same rubble trench foundation followed by a couple of feet of earthbags (to get away from ground moisture). A post beam structure would have been installed on top of that, followed by the strawbales. In the end I still chose earthbags. The home I’m building is in Tornado Alley here in KS and the bags make a stronger building. Earthbags are great for thermal mass. With the walls over 12″ thick, it will take half a day for the outside heat to reach the inside; thus, the coldest part of the night will be the warmest indoors and vice versa.

The downfall of all this thermal mass is that it has little insulation value. This is why I’m plastering the walls with 2-3″ of papercrete inside and outside. Scoria can be included in the earthbag mix to increase the insulation value of the bags, but there is not a good supply of this volcanic rock anywhere near me.

Q: Will an earthbag house stand up to earthquakes/tornadoes/fire/bullets, etc?
Answer: An earthbag house is very resistant to fire. The mix in the bags cannot burn. The papercrete could smolder if in contact with an ignition source for a period of time. However, the burn would be slow. This would allow plenty of time to locate the fire and extinguish it. When I install the final layers of papercrete, I’ll add sand to the mix which will make the plaster a bit stronger, minimize shrinking, and add additional resistance to fire (this also lowers the insulation value a bit).

Earthbag structures hold up well in earthquakes.  Nepal has received some publicity from their earthbag buildings withstanding their recent devastating earthquake. They also have a good chance of surviving a Tornado. The utility room I included in my building plans begins four feet underground and can double as a tornado shelter.

Q: How big is the house?
Keith’s Answer: The size of the living area measured by the outside of the structure is 1200 square feet. Measured from the interior walls, that space would be around 1000 square feet. The utility room is around 400 square feet measured from the outside. It contains the 3000-gallon cistern, most of the plumbing, the main electrical panel, and space for storage as half of the room is split into two levels (the cistern and lower part of the room are 4′ below ground level). If I were to build an earthbag structure for my wife and myself, it would probably be a third of this size. I’m building a structure this size because it is for my parents for their retirement. They’re accustomed to a much bigger living space. It’s also a central location (in the US) for my family to come together so the extra rooms will be handy for family and friends. Note from Lily: this is a major undertaking and we highly recommend starting out with a much smaller building if you’re thinking of constructing an earthbag house!

Q: Where did you get the design for the house?
Keith’s Answer: I considered Owen Geiger’s plans, but with my background in construction and the knowledge that I had learned about earthbag building (mostly from books), I felt confident in designing my own structure. Most of my knowledge came from the book, Earthbag Building. I Googled floor plans for a three-bedroom house, selected one we all liked, and then I redesigned the walls to conform to the design considerations for earthbag structures.  I added the utility/cistern room to the floorplan.

Q: How much will this house cost?
Keith’s Answer: The total cost of the house will be around $55,000 to $65,000 (the septic system alone is over $10,000 (subcontracted) and buried water/electric lines cost over $8,000 (all done by me with over 1000′ in trenches)). The labor costs will be between $15,000 and $20,000. The roof materials (trusses, plywood, metal roofing) purchased last week cost over $6000. The mix I’m using in the bags is taking about twice as long as what the estimate in the Earthbag Building book listed for a calculation. The book led me to believe that the screenings coming from the rock quarry would be sufficient for bag fill, but this contains virtually no clay, so I have to make a clay slip (make a clay pit, add clay, add water, mush to milkshake consistency, pour though 1/2″ mesh screen into barrels, dump out rocks) and mix it with the screenings in a cement mixer. This takes a lot of extra time, but I’m still very happy with the result.

Q: Where did you get ___? /  Where did you learn ___?
Answer:  Take a look at our Earthbag Building Resources post to find links to materials, books, videos and other things we’ve used to build the house and learn more about how to do it.

The Rainwater Cistern

Q: Why did you do an earthbag cistern instead of tanks?
Keith’s Answer: I primarily went with the earthbag cistern to keep the pricing down and have greater flexibility with the tank design. I had a custom made (9′ diameter 7′ tall with a 4″ overflow drain centered 6″ from the top) cistern liner built and shipped to me before I had even begun building with the bags. The custom liner was about 1/3 the cost of a 3000 gallon tank (<$500 vs. $1500). However, you will have to decide is the savings is worth the extra labor it will take to build an earthbag cistern tank with a liner.

By keeping the cistern built into the earthbag structure, I will not have to worry about freezing in the winter.

By having the round structure incorporated into part of the walls of the utility room and about 4′ below ground gives the rest of the room extra strength and an excellent place to hang out while tornadoes are in the area since my project is in the middle of “Tornado Alley.”

I did not want tanks on the ground surface since transporting rainwater from the gutters to the tank would have been more challenging with higher tanks.

My design is something I’m testing out. I could not find where anyone else has built this type of system anywhere on the Internet before building this one. If any problems come up, we’ll include them in the blog.  Recently we topped the tank off at 3000 gallons and installed the well/cistern pump which is now providing water for our motorhome and for use with the continuing construction.

Q: Why was it necessary to line your hole with earth bags? If the whole cistern was underground would that still be necessary? Or could you line the hole with the membrane?
Keith’s Answer: I wish it could be that easy, but digging a hole with vertical walls and installing a flexible membrane wouldn’t work as the pressure on the walls from the earth around the hole over time would collapse inward. I have researched building ponds and the slopes recommended were about a 5-to-1 ratio (five feet horizontal per foot of depth) to prevent the pond from filling in on itself. Burying a tank designed for burial would be your best bet, but you would still need a way to drain the water below it; otherwise, if the tank was empty and there was a heavy rain storm, your tank could float up out of the hole a bit.

When it comes to building with earthbags, a round structure is the strongest. They prevent the walls from collapsing in on themselves and the barbed wire between rows provides tension to help keep the walls from spreading outward. On the straight walls while building underground, I had to install two rows of bags to add extra strength to prevent the walls from gradually being pushed inward over time.

Q: How will the cistern operate in times when there is very little rainwater?
Answer: Keith designed the cistern’s size based on his estimates of how much rain this part of Kansas receives and the roof size where the rainwater will be collected, plus his estimate of how much water his parents will use. Additionally he took into account how much water could be delivered in one trip by a water truck. If the cistern runs low on water, they can call out the water truck that we used to have our last load delivered. For $75 “The Water Boy” can put in 2,500 gallons, and it should last them a month or so. That’s not too bad considering the monthly water bill in this area is about the same amount.

When it comes to building with earthbags, a round structure is the strongest.

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Q: How much did the cistern liner cost, and where did you get it?
Keith’s Answer: Our custom made 3000 gallon cistern liner cost around $500 including shipping, from polyfabrics.com. A hard plastic tank will cost around $1500 including shipping. If you have extra free labor available, you can save a bit using the custom liner. If you’re paying for some extra labor like I am, it may be better to go with a hard tank and build up the earthbags around it as necessary. I’m still glad I went with the custom liner so I can test out a method that few have used and/or documented well.

Do you have a question we should add to this page? Contact me and let me know, or ask in the comments section below!

Want to keep up with our earthbag house project? Enter your email below for updates! And be sure to share below if you have any questions, suggestions or comments!

Quick Earthbag House Update

It’s September 17th, 2015…I thought I’d pop in with a quick update on our earthbag house project.

We’re making slow but steady progress! One of the big blocks we’ve faced this year is the lack of extra help like we had last year. We have a part-time helper and Keith’s sisters both took time off work and helped for a few days, which was wonderful! We’ve put up more ads and are hoping to find more workers soon. […]

Papercrete Mixer Header

Papercrete Tow Mixer

Last year, making batches of papercrete involved filling a barrel with newspaper and water, and grinding it up by hand using a drill with a special attachment.  CLICK HERE to see last year’s post about it.

Using that procedure, we could only make relatively small batches of papercrete, and mixing it up that way always made my arms ache! Toward the end of the season last year, Keith began collecting the materials to make a papercrete tow mixer, using the one on makepapercrete.com as a model.  (Be sure to check out that site for a great demo video and to order step-by-step instructions if you’re interested in building one yourself!)

A neighbor near our property obtained the rear axle of a Jeep and welded it to the frame of an old boat trailer for us, and then Keith’s dad, Lee, assembled the contraption this winter while we were away.

Toward the end of the season last year, Keith began collecting the materials to make a papercrete tow mixer, using the one on makepapercrete.com as a model.

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Now to mix papercrete (a batch about 3 times the size of what we could make before) all we need to do is fill our mixer about half way with water, toss in 45 lbs of newspaper, drive around until it’s ground up, then add 45 lbs of Portland Cement and drive around some more to mix it up!  There’s actually room for more if we want to make an even bigger batch.

We’ll be putting a layer of papercrete, about two inches thick, on both the inside and outside of the earthbag walls to protect the earthbags and provide extra insulation against cold and heat. The papercrete will eventually be covered over with a lime plaster.

See photos and a video of our papercrete mixer below!

Papercrete Mixer Blade

The axle was turned to point upwards, then a watering tank with a hole in the center was affixed to the axle assembly and a lawn mower blade mounted onto the axle. As the wheels turn, so does the blade!

Papercrete Mixer Leak

Unfortunately, quite a bit of water leaked out the first time we filled it. It still worked, though! Lee later sealed up the leaks with more glue and grease.

Soaking Newspapers

We threw 45 pounds of newspaper into the mixer and made sure it was all soaked.

Partially ground up newspapers

First we tried to pull the tow mixer with a lawn mower. It wouldn't budge. So we switched to pulling it with a Jeep. It worked! Here's the partially ground up newspaper after a short drive of a few hundred feet.

Papercrete Tow Mixer behind Jeep

Lee pulled the tow mixer for awhile longer. In this photo you can see the half-built earthbag house in the background.

Paper pulp

Looking good! Time to add 45 lbs of Portland Cement and drive a few more minutes.

Papercrete ready to use

Here's the papercrete! Not bad for our very first batch. MUCH easier than the old hand-grinding method. We discovered that wetter papercrete is easier to use in the mortar sprayer.

Here’s our video of our very first batch of papercrete made with the tow mixer:

Any questions?  Feel free to use the comment box below!

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Earthbag Building Resources

In this post I would like to share a list of the resources we have used for building the earthbag house. I’ll update this page as we continue the project, so check back later or sign up for my newsletter at the end of the post to be notified when I add something new! […]

Papercrete

Papercrete? What’s that?

Papercrete is a mixture of paper and Portland cement.  It has a light, spongy, airy feel and it’s a great insulating material!  

Papercrete up close.

We’ll be applying one to three inches of papercrete to the inside and outside walls of our entire earthbag structure.  Because it can’t withstand the elements unprotected for long periods of time, we will eventually add a layer of lime plaster over the top of the papercrete.  (Once we get to that point in our building process, I’ll tell you more about lime plaster.)  This will protect the walls, while allowing them to breathe.

Papercrete is a mixture of paper and Portland cement.  It has a light, spongy, airy feel and it’s a great insulating material!  

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We covered most of our walls with it before going away for the winter, to protect the bags from UV radiation which would cause them to turn into confetti after a few months.

To make papercrete, we soak 18 pounds of newspaper in 25 gallons of water in a 55 gallon barrel.

Soaking 18 pounds of newspaper in 25 gallons of water.

Once the paper is well saturated, we add 18 pounds of Portland cement and mix it all up into a goopy mush.  This is pretty hard on one’s arms, which themselves begin to feel like mush after a few minutes of mixing!  There is a way to make a giant mixer that you can tow behind a car, and we have the materials to put that together, so when we go back to work on the house this summer it should be easier!  I’ll write a report on that mixer once we’ve built it.

To make papercrete, we soak 18 pounds of newspaper in 25 gallons of water in a 55 gallon barrel.

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Once the consistency is right, you have to work with the papercrete right away before it starts drying out.  The first step, when working with a bare earthbag wall, is to hurl handfuls of the mush into the cracks between the bags.  It seems to stick better when you throw it, rather than pushing it in or trying to smear it on with a trowel, although once the first layer has dried a bit it becomes easier to push more papercrete in with your hands.

Fill in the cracks between the bags before putting on the outer layer of papercrete.

Once you have the cracks filled in and the wall is smoother, you can then use a mortar sprayer to quickly coat the entire wall in a layer of papercrete.

A whole wall coated in papercrete.

We have placed wire in strategic locations along our walls, so that after the first layer of papercrete is applied we can attach chicken wire to the wall for added strength, and apply more layers of papercrete.  The more papercrete we have on the walls, the more insulated they will be.

In addition to spraying papercrete onto our earthbag walls, we have also experimented with making papercrete bricks.

Papercrete bricks.

With papercrete, we can make any size or shape that we want–though the bigger stuff takes longer to dry and may fall apart if you get impatient and take it out of the mold too soon!

Our papercrete brick mold.

Check out this video, where Lee and Keith demonstrate the process of making papercrete:

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Doors and Windows in an Earthbag House

We install doors and windows a bit differently in an earthbag home than in a normal house.  Watch the video below where Lee explains how it works, and enjoy the slideshow afterward which shows the doors and window frames in the earthbag house we are building: […]

Cistern Part II

A few weeks back I wrote a post about the rainwater cistern we’re building.  We’ve made a lot of progress since then!  My newest video shows the cistern from dream to (almost) done!

This cistern, made of earthbags like the rest of the house, will be the primary source of water for the house.  We’ll collect rainwater from the roofs of the house and the RV shelter (both of which will be metal).  The water will be used for washing, bathing, and–after running through multiple stages of filtration–drinking.

As you’ll see in the video below, the cistern has various layers on the inside.  We covered the earthbags with papercrete to fill in the grooves and make a smooth surface for the liner to rest against (more about papercrete coming in another post).  Because of the immense weight of the water inside the cistern, we mixed a greater proportion of Portland cement, plus sand, into the papercrete mixture to make it stronger (regular papercrete contains half paper and half Portland cement by weight, and no sand).  To further increase the strength of the papercrete and give it something to stick to, we tied chicken wire to the sides and added more papercrete.

This cistern, made of earthbags like the rest of the house, will be the primary source of water for the house.

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It took several days for the papercrete to dry, and we used fans, heaters and lights in the cistern to help speed up the process since the weather outside was turning cold.

Once the papercrete had dried, Keith lined the bottom with gravel, plastic, an old tarp and styrofoam for protection from moisture and abrasion.  He made the center of the cistern a few inches lower than the sides, and will put the pump there.


He also hung old tarps in the cistern to act as a barrier against the more abrasive papercrete, so that the cistern liner would have yet another layer of protection.

Then it came time to put the cistern liner in.  Keith had this custom made before we had even broken ground, and it was a perfect fit!  Several of us worked together to unfold it and stretch it out around the rim of the cistern while Keith screwed it down.

Then Keith lowered me inside and I stretched the liner out along the floor and against the walls of the cistern.

Lastly, all of us worked together to carry over the enormous wooden lid that Lee had made for the cistern.

We hoisted it onto the rim and then held it up temporarily with stacks of boards while Keith went around the rim with caulking, and then we lowered it into its final place resting place.

A little hatch in the lid provides access into the cistern if we need to go into it in the future to clean it or make repairs.

It’s quite the project, and one of the final things we will have worked on for this season.  The weather is now too cold to work with earthbags or papercrete.  We’ll get back to the project next spring!

Meanwhile, I will upload a few more posts about what we have done on the earthbag house this year.  Enjoy this video showing the cistern from start to (almost) finish!