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Clay Finishing question from Uruguay

October 8, 2018

Spanish: Hola! tenemos una casa de barro en uruguay y nos gustaria saber mas sobre como tratan el barro y como dar un buen acabado! muchas gracias
— Carolina from Uraguay

English translation: “Hello! We have a mud house in Uruguay and we would like to know more about how they treat clay and how to give a good finish!”
—  Carolina from Uruguay

Dear Carolina:

Finishing clay or stucco can be considered easy or difficult depending on how much work you decide to put into it. It is always much easier to get someone else to do the work, such as a paid professional.  🙂

The outside of our tire bale house is stucco– a mix of concrete and sand and some chemicals to seal each layer of stucco.  We put the stucco on in 6 different layers. The product is from Sto Corporation (  ) from Germany).   Applying stucco is like painting with peanut butter (mantequilla de maní).
The stucco is troweled on using standard concrete trowels. If you like textured walls, you can leave trowel marks.  (We like textured walls versus smooth walls.)
Each different layer has come kind of protectiveness to it and interestingly, each layer is a different color.    (To see the layers in Sto’s products and to understand their products before using them, visit  ).

The clay on the walls inside of our home was much easier since the clay is not the consistency of peanut butter.  Instead, it is like wet sand at the beach. However, we had to trowel the clay onto the walls one layer at a time.  Each layer could not be thicker than that of a credit card or less than 9.5250 mm thick.  Only 2 layers were suggested for our application. We also finished the clay with a product that helps to keep it from shedding. I think that product was a masonry primer.  A good stucco person would know the best product to use to keep the clay from shedding.  We used special small trowels for the clay application.
Smoothing for the clay walls inside was done with water in spray bottles and thick sponges. Spraying on the water and wiping the sponge in the horizontal direction. As the clay dries, you can always come back and smooth some more as long as the clay is wet. Since the clay has lime in it, chemical gloves are a must to wear when mixing or applying clay.

An interesting possibility when using clay is to make use of stencils in areas where you would like to be a bit artistic.  The layers of clay will have to be much thicker here to accommodate the stencils.

Since Uruguay can be a wet environment sometimes (Colorado U.S.A. is very dry), I suggest seeking the advice of an experienced stucco person there. They may have a much better opinion of the best products for your environment.

I hope some of this information helps your project.
Best wishes!


2018 Update

September 11, 2018

Some have wondered if we are still alive & kicking in our mountain home. YES!
All is good here in the Rocky Mountains. The house is still performing beautifully as planned. We are in process of installing a 2nd solar array & hope to have some more data to post in a few months on how well we are conserving energy, making energy, & living in/using our lovely thermal mass tire bale home. The plan is also to post some new pics.
Our other website has recently been redesigned for simplicity & faster load time (less pics).
Stay tuned for more data……..

Changing faces…..outside

August 27, 2013

This summer our project has been to change out the grey gravel on our courtyard to flagstone. The reason we decided to do this is amusing: Our dogs “fly” out the front door and gravel gets caught between their toes thus as they fly, they toss gravel into the windows and glass front door. We did not want to have the added stress of replacing windows or front door, so we went with flagstone. We will monitor the temperatures over this next winter to see if there is a drop in overall radiant temperature due to this change. The grey gravel extended our passive solar heating capabilities a bit, which makes the house warmer in the winter (which is ideal). The flagstone will (like the gravel) extend our thermal mass somewhat.

Hagar tire bale home, new flagstone front entry 2013

Hagar tire bale home, new flagstone front entry 2013

Presenting at IEEE Green Technologies Conference, April 4-5, 2013 in Denver

February 25, 2013

We will be presenting data from our paper “An Examination of Multiple MicroGeneration Technologies used within an Experimental Home”, based on the data that you have seen posted here on our blog, at IEEE Green Technologies Conference, April 4-5 in Denver, Colorado.

If you would like more information on this conference, the keynote speakers, or to take a look at some of the other papers that will be presented, here is a link  IEEE Green Technologies Conference.

2012 Energy Use and Production Compared to Other Homes

December 12, 2012

So I promised in January (!) that I’d supply more data on our energy use and production. I hope that no one has been holding their breath!
Here is a sample of our energy production Jan-Oct 2012 using our single 6 panel (230 Watts each) PV array.  Yes, 2011-2012 was considered a very mild winter with little or no moisture or snow but LOTS of SUN!

Hagar Tire Bale Home Energy Produced Jan-Oct 2012

Hagar Tire Bale Home Energy Produced Jan-Oct 2012

And, here is a snapshot of indoor/outdoor temperature comparisons (in Fahrenheit) for Jan-Feb 2012.  (Click on the image to enlarge it.)

Temperature Comparison Jan-Feb 2012 for Hagar Tire Bale Home

Temperature Comparison Jan-Feb 2012 for Hagar Tire Bale Home

As you can see, the graph illustrates how steady the temperatures inside our home can be (and quite comfortable too). (Click on the image to enlarge it.)  We began our days bundled up in sweats and were often found wearing t-shirts and shorts by noon each day.  As the sun set near 4 pm, we were back in our sweats.

Here is a snapshot of 3 different types of homes and their electric usage in kWh. Interesting comparison.  (Click on the image to enlarge it.)

3 different homes and their electric use in kWh for 2012

3 different homes and their electric use in kWh for 2012

What other data do you feel would be meaningful to illustrate the energy possibilities or efficiencies of our home?

Oh humidity

February 25, 2012

Recently, I shared an exchange with someone who built a tire bale extension to his straw bale home. Here is a link to his home picture history.
Tire bale homes HOLD HUMIDITY. So if you’re planning to build in a geographic location that is known for humidity, there are some things you should consider changing.
For instance, we have no HVAC–heating air conditioning system–to physically MOVE air which can help remove humidity. Yet, our home exchanges 37% of the air at least 3 times a day–more in summer when the windows are open more.
Second, our windows are NOT slanted on the south. Our windows are floor to ceiling straight up and down but, even our windows condense when temperatures drop down to 5-degrees F or below. I keep microfiber clothes in them to help keep the water away from the window seals. I chose Weathershield windows since they seemed to be the best built and guaranteed for the longest. Also, these windows are made in the U.S.
Last, we chose NOT to put an indoor planter (which in some of these houses is used to treat grey water). We do have 6 full sized trees and a number of other plants in small portable (roll around) planters. Plants put a lot of humidity in the air, which is good for our skin and noses.
So, consider these things as you approach your building project. And, seek advice from others who have built these structures before you finalize your designs.

Two More Tire Bale Homes Under Construction in Colorado

October 20, 2011

Hello world! I’ve been notified of 2 more tire bale homes under construction in Colorado and wanted to share the info with anyone interested in building a home of this type.
First, I would like to let everyone know that our home is toasty warm once again this fall/winter, and was delightfully cool this past summer. Given that our solar system was working hard for us, our electric bill was never more than $20 (actual kwH) and we had none of all that noise and pollution from an HVAC system. We entertained many guests this summer, one of whom has one of the homes under construction.
Notice that each home is different? That’s the beauty of these kinds of homes.
Without further ramblings from me, check out these homes.

Here is the first house Mikey designed and it is mostly complete
Here is a recent home completed that Mikey designed and, they recently received their Certificate of Occupancy (CO letter)!.
And, here is one of Mikey’s latest designs
OK, this is the last one that I know of….to date.

Here is a flikr stream of our progression

I hope that you found Michael Shealy (Mikey), Touch the Earth Construction (

Helpful Books on Passive Solar Homes

January 25, 2011

Just wanted to let everyone know about a few books that I’ve found recently that are very helpful in understanding WHY to build your passive solar tire bale home a specific way; why to do your research before you design or build, and why to use an experienced architect or designer in these types of houses. I’ve been doing research for our book, which I cannot tell you when will be complete, only that I am working on it.

So here goes………all great references and all available through (I bought mine used and saved some money.)

The Solar House Passive Heating and Cooling by Daniel D. Chiras, 2002, Chelsea Green Publishing, White River Junction, VT, ISBN 1-913498-12-1 paperback. This book is helpful in understanding how to supply heat sustainably, energy efficient design, indoor air quality, types of wood stoves, windows(!) and their coverings, orientation and so much more.

The Passive Solar House The Complete Guide to Heating and Cooling Your Home, by James Kachahadorian, 1997, 2006, also published by Chelsea Green Publishing, White River Junction, VT, ISBN 1-93392037-03-7. This book has some of the most basic things to understand when undertaking a passive solar home. It also has some of the best formulas needed for this type of architecture. This has been one of my best resources!

Solar House Basics by Peter Van Dresser, Passive Solar House Basics,, 1977, 1979, 1995, Peter built his first solar home in the early 1950s. This is my 2nd best reference for passive solar homes. I love the illustrations and the brevity but all the very good information.

Passive Solar Buildings Solar Heat Technologies: Fundamentals and Applications, edited by J. Douglas Balcomb, 1992, MIT Press. (part of a 10-volume set). Balcomb is one of the key figures in many areas of passive solar heating and cooling technologies and on the formulas that many architects must know when designing these types of homes. He also works with the Passive Solar Industries Council. There is some information on performance modeling in this book that may also be found in materials from the American Solar Energy Society (ASES).

As I reflect back on our building experience, I have found that if I had a checklist of very important data to keep in mind when designing our home and then building it, we would rate about 80% of doing what these authors have recommended for this type of architecture.
For instance, there is a sort of checklist outlined in a chapter in the last book called “Elements of a Passive Subsystem”. Check this out as you design or build your passive solar tire bale home. You will find that it will save you money in the long run.

Happy research and building!

ASES Solar Tour Success

October 6, 2010

Thanks to the visitors who took time to listen us explain and brag a bit about our accomplishments with our passive solar, thermal mass home whose structural integrity is made from 170 tire bales (over 17,000 used tires).
We also learned from our guests of their projects, which was another exciting part of our day…the exchange of ideas.
We discovered that we are not the only “different” people out there.
Thanks also to the people at Grand County Business Economic Development Association (GC BEDA) and American Solar Energy Society (ASES) for putting this tour together and sponsoring it.
Mark your calendars for next October for the next ASES Solar Home Tour.

Using Materials on Hand…

October 6, 2010

The interior of our tire bale home is about 98% complete. The guest shower is now complete. Now all we have to do is add blinds to the east end of the house to be 100% complete. We’re hoping to have the money to add the blinds this year.
Exterior work for our home included adding a solar system this year, which we completed on 7/27/2010. It is almost paid for before proceeding with the last interior item. Also on our list this year for exterior work was the addition of a pergola.

Hagar pergola

Hagar pergola

We were able to use materials on hand to complete this much needed “piece of shade” (thanks to our neighbor Carol who gave us some logs from an older cabin at her place). Duncan was able to pick up a piece of astro turf on a closeout sale to create a usable floor for the pergola. We had thoughts of gravel but that can wait. We used some leftover tires to create steps–pounding dirt into tires then covering them with concrete. (Boy! Am I glad we did NOT build our house by pounding dirt into tires. We might still be at it though using far less tires! Whew!)