This picture is compliments of Castleton State College student and Cornerstones/AiA volunteer Ben. Ben was one of the Castleton students who was honored with ringing the new bell gracing the San Miguel Mission during the commemoration event last week. The automated bell striker was not quite operational yet so the ringing was accomplished with hammers. However, after about 5 minutes of manually striking the bell, the new bell struck back!
On ADOBLOG we will be chronicling the projects and events that Adobe in Action is organizing and working on. We will be making our best attempt to produce timely updates relating to the organization's progress.
Pictured above is the San Miguel Mission in Santa Fe, NM, widely regarded as the oldest church in America. Tonight was the dedication of the bell tower restoration which contains adobes made by Adobe in Action volunteers. Additionally long-time AiA volunteers from Castleton State College in Vt. were honored with ringing the bell to commemorate the dedication. A great example of Adobe in Action volunteer made bricks being used in the community to promote adobe. Also a terrific evening for our friends and partners at Cornerstones who do such a tremendous job in preserving and restoring Adobe treasures throughout the SW.
Pictured below are the first couple of batches that we have made at both of our indoor off-season sites. We are starting with a traditional mix of clay rich soil ( screened soil which is naturally composed of clay, silt, and sand) water, and straw. Additionally we have made some adobes with a paper-clay mix (adding cellulose fiber to the clay for additional brick strength). We will also be experimenting with horse manure and other weatherizers to help protect our adobes from water erosion and breakdown.
So far we have been encouraged by the results related to our fledgling indoor brick production. While we have recorded temperatures as high as 120 degrees in the greenhouse and hoop house there has been no significant cracking in our bricks even though the bricks have no additional sand (see earlier adoblog entry for context).
Additionally our bricks have been drying quickly enough to move them from where they are originally made within about 4-5 days. This is consistent with our outdoor summer production process. We will be making more test bricks this weekend and next week's temperatures outside will begin flirting with 32 degrees so we will see what effect that produces.
If you’ve followed adoblog this summer you know that two issues that require attention making natural adobes during the warmer months are cracking and monsoon rains.
The cracking is caused by producing adobes that are exposed to the intense direct sunlight and windy conditions. The bricks tend to dry too quickly which leads to cracks that can be significant enough to break the bricks apart. The solution is to add more sand to the mix. The sand that we add is washed concrete or arroyo sand that adds aggregate to the brick, reduces the amount of clay by about half, and allows the brick to dry more slowly. The result is no cracking. However this also makes the bricks much more susceptible to water erosion from driving rain storms; which coincidentally occur quite often in the desert southwest in the summer (this summer’s monsoon rains counted almost 7” of rain in July alone). So this leads to the rather tedious and time consuming process of constantly covering (protection from rain) and uncovering (for adobes to dry) the adobes in the field.
This summer we also had our adobes tested with AMEC Earth and Environmental Lab in Albuquerque, NM. The lab will test adobes for two specific areas required in the NM Earthen Building Code: compressive strength and modulus of rupture. We made bricks available to the lab both from the supply we made this summer (bricks that had added sand to keep them from cracking) and adobes we had made a few years before with no added sand. The bricks that we gave them with no added sand were made undercover and out of the direct sunlight. They were able to dry a little more slowly and therefore developed no significant cracking.
The results of the tests were very interesting. The bricks that we made with additional sand this summer were just at the minimum requirement for the code in the compressive strength test and comfortably above the threshold for the modulus of rupture test. The bricks that we had made two years earlier, and had even been exposed to some weather (snow and rain), doubled the necessary result in modulus of rupture and almost tripled the required amount for compressive strength.
Needless to say those test results got us thinking about the possibility of adobe production in spaces that were partially or wholly covered. We will see if brick production in an indoor greenhouse space will allow us to consistently produce the kind of brick that tested so well with the lab.
For the next few months, until spring actually, we will be producing adobes during what is normally the off-season because of freezing temperatures. Thanks to two partner organizations in Santa Fe: The Santa Fe Community Farm and the Agua Fria Nursery we have acquired some greenhouse/hoop house space where we have begun to make adobes. We are working with an intern from Santa Fe Community College and gathering data on the efficacy of adobe production during colder months. We also are interested in experimenting with different adobe mixes for increased strength and water resistance. We will continue to update you on our progress. In the meantime here's some pics of our sites and benefactors:
Roy and Blondie at the Santa Fe Community Farm Greenhouse:
Bob at our Agua Fria Nursery site: