Cob Art Studio - Arivaca, Arizona

Large Calcite Slab Placed in Kiva Room

2012-01-06T14:57:00.000-08:00

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I became obsessed with translucent nature honey-amber colored Honeycomb Calcite after seeing it at the Tucson Gem Show in Tucson back in 1999. So much in fact, that I formed a entity to sell the stone after developing a business relationship with the owners of the calcite mine. I saw the potential of the stone as an artistic architectural element in the adobe buildings I was designing for the future at that time. The future has arrived as the building projects are moving forward.

As envisioned for the studio building project, I took the largest stone I had in my calcite inventory and spent several days removing the white outer layer of the stone with chisels and a grinder. Then with the help of two friends, raised the 197-lb stone up scaffolding to the position where it was placed on the north side of the circular 'kiva room'. To hold the stone in position, rebar was employed as bracing using protrusions in the stone as handles for the rebar to rest against.

The thickness of the wall at this location is approximately 3-feet, thus the stone will not be illuminated by sunlight. Instead, a solar-powered lighting system will be installed in a wall cavity behind the stone in order to illuminate its features for viewing inside in the kiva room. Future posts will show additional building steps for both the wall and the lighting installation.

Southeast Room

2012-01-02T13:29:00.000-08:00

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This extension (shown at right in top photo), added off the southeast side of the main (large) room, was envisioned as additional space. But more importantly, I saw the need to add a passive-solar gain room to collect sunlight in the winter months. Since a french style door will separate this room from the main room, it could be closed at night to retain the heat in the large room accumulated from the passive solar style design.

In the above photo of the solar gain room, the concrete bond beam (discussed in previous blog entries) is shown at top hugging the curved wall. The stone stem-wall extends up 3-feet from the footing. The room dimensions are approximately 7'x10'. Ceiling height for this space will be about 8-1/2 feet.

A Footing in the Sky Poured

2011-11-08T18:39:00.000-08:00

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The Masonite forms as discussed in the previous blog held-up excellent during the pour. The concrete mix for the bond beam was 3-gallons water, a half-bag of Portland Cement (47-lbs) and 350 lbs of gravel/sand. This recipe was derived from several books I have on concrete that would give me a suitable mix for footings and foundations. Initially, I weighed a 5-gallon bucket with the sand/gravel mix. It came in at 70-lbs. So then I knew to add 5-buckets to the mix in order to achieve the 350 lbs called for in the recipe.

Myself and a helper took 3-hours non-stop to mix the concrete (6 mixer batches) and haul the concrete up scaffolding in buckets to accomplish the task. Approximately 1-ton of concrete was used in this pour.

To begin working on the roof structure is a psychological milestone. There is still additional 'cobbing' to be done to raise the main room's wall height to 12-feet, so effort over the next few months will switch back-and-forth from working on the walls to working on the sections of the roof structure.

Devising a frame to support the bond beam pour

2011-11-07T22:01:00.000-08:00

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Since the start of this building project, I have been thinking about how I would set-up framework to pour a concrete bond beam (description mentioned here) on top of the cob walls at ceiling height.

In short, the bond beam ties the wall with the roof through the use of vertical rebar from the footing through to the roof structure. In addition, the bond beam act to distribute the compression load from each viga supporting the roof structure as it rests on the bond beam.

The challenge for this building design is to support the frame around curved walls. Since the width of the walls for this southeast part of the building are the minimum desirable thickness structurally (12"-17"), this necessitated that the bond beam span the full width of the wall for the entire length of the room. To achieve this, the support frame had to fastened to the outside of the cob wall. This fastening method had to be figured-out.

I was also thinking about what material would be flexible enough to bend around the curves of the walls; while at the same time knowing the material had to hold firm during the pouring and curing of the concrete.

I decided to go with 3/16"-thick Masonite (sold in 4'x 8' sheets) for the bond beam frame and 12"-long 1" x 2" furring strips to support the Masonite.

For the frame, I cut 12" wide strips of Masonite, eight feet in length from the sheet. I pre-drilled three holes in the furring strips in order that the screws securing it to the cob walls, wouldn't split the wood or make the attachment process more difficult.

The screws I chose were 4"-long deck screws (course thread). I was impressed how the cob (straw/clay) mixture held the deck screws extremely firm when attaching the furring strips in support of the Masonite frame.

The photo at top shows the completed bond-beam form prior to pouring the concrete. The photo at the left is a close-up of a section of the wall. The rebar used was 5/8"-diameter and additional furring strips were attached across each side of the wall to provide additional stability to the forms.

In the top-left quadrant of the photo above, there are two "Simpson Strongties" - a trade name for metal straps that will be secured in the concrete beam and rise vertically to attach the viga to the bond beam.

Upon the completion of the bond beam's support fabrication, I knew I had tackled the challenge of the form's design and implementation. But I still had to mix and pour the concrete beam, so I was careful not to declare the design a success just yet.

Clay/Straw Walls Hold Strong After 12-inches of Monsoon Rains

2011-08-25T23:50:00.000-07:00

Artistic Note: Regarding the photo below, check out the clouds in the background. My camera's imaging chip seems to have made those clouds look 3-dimensional and painterly - a cool effect! To get a larger-size view, click on the photo.

The cob walls have held-up well, with little erosion, over the course of this year's summer monsoon season. The rainfall tally (so far) is over 8". It's quite amazing how cob holds up to the pounding monsoon downpours.

The walls are now about 8-feet tall on the southeastern room of the studio. Therefore I need to establish the final height for this section of the building, which will be lower than the (adjacent) room, that will have a higher wall height wall height that is adjacent to the north of this room. I used a surveyor's level to assist in establishing final height. I'm there in the background holding a ruler (this one too big to take to school) that I'm using in conjunction with the survey level.

I struck a line on the scale at a point on the wall that I considered final height. Then at intervals along the wall where there was vertical re-bar sticking up, I moved the ruler up or down until the line I made on the scale was in the cross-hairs of the surveyor's level (My wife was attending the level - Thanks honey!!). Then I made a mark on the re-bar at the height of the line I made on the ruler.

Next I ran a string (as shown in above photo), tight along the mark made on each piece of vertical re-bar along the wall. The string now represents a uniform height. Now I can build-up the wall with cob to the height of the string and be confident that I have a "level height" along that section of the wall.

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Summer Harvest of Sand and Gravel

2011-08-23T10:54:00.000-07:00

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To the left of this photo is a rock check-dam (a.k.a.Gabion) which helps keep soil in place when the dry-wash across my access drive to my property flash floods during the summer monsoons.

A few weeks back a flash flood deposited an enormous amount of sandy-gravel across the driveway. This sand is just what I needed for the bond beam I will soon be constructing along the top of the cob walls of my studio. The bond beam helps support the wall and tie together the wall and roof structure. In addition, the bond beam will distribute the loads carried by the wood vigas that support the ceiling and roof structure.

Below. Drawing showing representative bond beam placement on adobe wall.

Drawing Source: Earthbuilders Encyclopedia by Joe Tibbets

A side-benefit of the gabion slowing-down the water, is that it allows the deposit of sand. This is an example of how you can harvest resources from your property for use in natural building. A result of constructing the gabion is a renewable source of sand for my building projects.

There is a financial savings aspect to this also. A 10-yard truck load of sand is around $150. But because Arivaca is so far off the beaten path, the sand/gravel company adds another $125 for the delivery charge. So that's almost $300 in savings in exchange for the physical labor in moving the sand myself.

For my blog on the construction and status of this gabion see:

LIFE OF A GABION

North View

2011-08-20T09:46:00.000-07:00

Summer has brought rains which means some nice vegetation growth including wildflowers which can be seen in the foreground of the photo. This photo looks north at the south side of the studio. Notice the generous window area that will allow winter sun to enter the space and warm the interior.

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A Micro-Chaco?

2011-07-03T22:58:00.000-07:00

Pueblo Bonito, Chaco Canyon, New Mexico

I was able to get my hands on some Department of Homeland Security aerial surveillance photos of the borderlands area and was able to locate my property. It was an interesting perspective - seeing the resemblance from the air that my studio under construction (below) has to Anasazi ruins at Chaco Canyon (above). Of course not quite the scope, but the architecture at Chaco Canyon was my inspiration.

For more on the Anasazi Architeure that inspired my cob studio, click on an earlier blog link HERE.

Southwest from the Interior

2011-06-23T23:09:00.000-07:00

It wasn't easy, but it felt good to finally get cob on the walls above the large window. Over 900-lbs of clay/straw mix was applied just to cover above this opening (see the wet - dark colored earth in the photo).

Supporting a portion of this mass of cob, a concrete lintel spans the above the 6"-wide rough frame, but only for that width. Across the rest of the main wall's 2-foot thickness, are oak and mesquite logs, debarked to expose their attractive hardwood interior.

The oak beam arching high over the window is now elegantly integrated into the earthen wall, adding to the fingerprint that will make up this structure's architecture.

To the right, the mesquite beams spanning a 3-foot thick stone/cob passageway, of a design inspired by Anasazi builders over 1,000 years ago in northwest New Mexico; a the center of their world - Chaco Canyon.

The 3-foot thickness of that west-interior wall means a tremendous amount of work mixing and hauling cob onto that portion of the building's wall. However, the 3-foot thickness is more than required for structural support. All that effort is critical in achieving the aesthetic for that space, and as integrated into the overall structure's design. I call this wide space between the two main rooms of the structure - a 'passageway'. That's the difference in 'feel', a thick wall achieves, compared to a thin wall. A passageway represents an opportunity to make something more meaningful by utilizing that thickness in the wall as an important part of the architecture. Since each room will have it's own feel, the passageway must be part of that transition between the 'feel' of each room.

When I see that passageway design in Anasazi architecture, I always sense that it must of had some meaning. We can only speculate; but someday when the construction is done and I'm 'in' that space; I'll hoping to gain some insights into why the Anasazi designed and built the way they did. Maybe I want to feel how the Anasazi must have felt when passing between sacred rooms in their great structures at Chaco.

For this portion of the studio (so far), I am pleased at the 'look' that originated from ideas when selecting a particular beam for that location.

As building continues I develop ideas in both practical and artistic designs. When constructing a building, you must have a balance between the two, or you end up with a building that's either not practical; or not artistic.

Realities

2011-05-30T21:38:00.000-07:00

"When one is building, one must not forget realities"

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A forest-fire that began on Memorial Day in the Coronado Forest southeast of Arivaca, rages in the background in the above photo. I was hoping the fire would stay on the south side of the mountain range, but that night through binoculars I could see bright flames as the fire made its way north over the ridge. Luckily directional winds and back-burning by the firefighters deprived the fire of fuel and were able to get it under control about 10-miles away.

South Wall

2011-05-23T22:23:00.000-07:00

I haven't posted a photo of the south wall in a long time. It's starting to take shape now. I finally have all the lintel (beams) above the doors and windows and now can begin to add cob to the walls without any significant interruption until roof height.

The larger window at the center of the photo will provide passive solar gain to the 'main room' during the winter months, when the sun angle is lower in the sky. The wall height in this room may reach 12-1/2-ft. The studio itself is a relatively small structure, so to create the illusion of a larger space, I selected the large window and the 12-ft ceilings in order to achieve a sense of 'space'.

Mesquite Beams Across Passageway

2011-05-20T06:42:00.000-07:00

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Mesquite beams have been placed across a passagway between the kiva room and the main room. The thickness of the walls in the passageway are approximately 3-foot thick. These are the beams mentioned in the previous blog. Each beam is 8-foot in length, approximately 8" in diameter and weight between 150-220 pounds each. It took about 1-day per beam to strip the bark off the logs with a draw-knife, sand the beam and apply tongue-oil to bring out the texture of the wood and help with preservation.

The next posting will detail the placement and securing of these beams.

Beauty Under the Bark

2011-03-28T22:38:00.000-07:00

My previous post showed four mesquite beams cut and ready to be debarked. Removing the bark off a fresh log is tedious work. I thought of just leaving the bark and raise the beams-up as they were: However, a few considerations changed my mind...

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My first thought was for a more practical reason. The softer outer bark on the mesquite wood is attractive to 'powder-post' beatles. By removing the outer bark the inner hardwood becomes a less practical habitat for the beatle.

My other consideration was more philosophical.......I know Mesquite wood has a beautiful finished grain texture - thus an impressive visual appeal. Despite the daunting-task of debarking four logs, I figured I would be 'short-changing' the aesthetics of the building by keeping the bark intact. In order to bring this hardwood to its full artistic potential, I made the decision to remove the bark.

Using a draw-knife as shown in the photo above, I worked off the soft layer which was in some places 3/8"-thick. At first I thought I would need to only strip about 180-degrees of bark (halfway around the log) - since the top half would have cob piled on it and thus not seen anyway. However, I had to drop that idea, because I wasn't sure how the logs would have to be rotated once lying next to each other in order to achieve a tight fit above the span. Each log has a unique curve to it. If I couldn't get them to fit-tight, then the gaps between each beam lying side-by-side each other would be almost too large.

A tighter fit is preferred especially when additional 'cob' will be placed on top of these beams (spanning the room divide), in order to continue the wall up to roof height.

As I continued peeling, I started realizing that I was doing the right thing. The debarked log looked spectacular. I coated it with 'Tongue Oil' to help preserve the wood and protect it from the elements.

The log shown took me about a day to accomplish by hand. Presently - one down - three to go.

Tedious for sure. But now at least I'm assured at what to look forward to, artistically, once the building is complete.

Beams for Passage Way

2011-03-06T22:59:00.000-08:00

At center-left of this photo you can see a passageway that divides the large room (foreground) with the circular Kiva room (not visible). The stone and cob wall that divides the rooms is almost 3-feet thick. In order to continue the wall above the passage-way I need to span the divide with 7-8 foot long & 8-10 inch diameter beams.

The most plentiful local hardwood in the Arivaca area is Mesquite. Mesquite is a very dense wood that make it ideal lintels over doors/windows and passage-ways (so hard it dulls saw blades fast!). Note: Residents of Arivaca harvest the trees seed pods for milling when dried into a wonderful- nutty flavored flour rich in nutrients (link to info on Mesquite flour).

I have land in a canyon where a Mesquite Bosque is situated in a dry wash area. I was able to selectively harvest the 4 beams I need to span the opening. The hardest part was lifting the mesquite logs. For example, the log lying flat in the photo is 8-foot long and 10" in diameter. It weights over 250-lbs. I could barely lift one end to position at the end of my truck's tailgate to slide it into the bed for transport. Inches at a time, I finally loaded them all in.

The next step will be to strip the bark off to expose the beautiful texture of the wood (see other posts in this blog for photos showing the attraction of finished mesqite lintels.)

Walls Above Window Height

2010-12-14T22:51:00.000-08:00

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With December day-time temperatures in the mid-70's here in southern Arizona, it's a perfect time to cob walls. Friends Greg & Katie (shown in the photo) applied about 500-pounds of the walls clay/straw mix (cob) over the course of two days.

The highlight was spanning a doorway entrance with oak beams and cobbing over it.

At the bottom-right of the photo, a concrete lintel is visible. Rising from the top of the concrete beam above the main doorway, are metal straps that will assist in securing the (forthcoming) oak beams that span the with of the wall on each side of the doorway.

Greg, Katie - Thanks! Your enthusiam and interest in the ideas and methods behind this project are really what it's all about....Bart

Oak Beam

2010-09-14T22:21:00.000-07:00

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Last year I purchased a permit from the Forest Service to harvest down-and-dead wood. So I ventured out in the national forest during the month of October and found this storm-toppled oak tree in Warsaw Canyon. I was able to cut a eight foot log from the tree which was very solid and HEAVY, so I had to be careful of straining my back loading that 8"-diameter sucker in the truck.

I needed to span a beam between two rooms of the studio. So I placed alongside the oak log an 8-foot laminated beam that I found in a construction dumpster. This created a combined beam width of about 12-inches. That width of the two side-by-side beams allows me to continue the cob wall above the 'beamed' span.

Thinking about the time when I found the beam and the 9 or so years it was stored.. ...reminded me that now would be a good time to say thanks to my friend Jim for letting me store that laminated beam in his garage for years, and for having patience with my vision that I would someday construct an adobe around that beam.

Status Photo

2010-09-09T20:46:00.000-07:00

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Anasazi Inspired Space

2010-09-07T19:54:00.000-07:00

This 10-foot diameter circular room was inspired by visits to Chaco Canyon in New Mexico. There is still much clay-straw adobe to add, especially to these walls that exceed 2-feet in width. Planned is a massive 200-pound slab of translucent Honeycomb Calcite stone, that will be placed in the wall and backlit with solar-powered lighting inside the wall.

This space will be the heart of my digital video editing & post-production studio. My goal was for the stone, earthen walls and illuminated translucent calcite to provide the feel of an ancient environment, in which 21st century digital film projects will emerge from.

Summer Rains

2010-09-02T20:32:00.000-07:00

I get comments from people wondering how clay-straw mix called 'cob' hold's-up to rain during construction (prior to receiving a lime based plaster on the exterior walls). The answer is quite well. We had about 8-10" of monsoon rains here in southern Arizona this summer and their was minimal erosion to the walls.

The clay on my land contains almost no sand and I don't add any to my mix. I just add more straw to account for the expansive properties of the clay. Cob is a fantastic building material.

Walls at Window Height

2010-09-01T18:52:00.000-07:00

Additional cast-in-place lintels are being constructed now that all the walls have reached window height. I have previously discussed the process shown in the photos below in an earlier posting - click here

The only difference from the previous cast-in-place lintels is that I have added metal retaining straps that will be secured in the concrete and extend out the top of the lintel to hold additional wood beams that span the width of the window opening (stay tuned).

Laminated Beam

2010-01-16T00:25:00.001-08:00

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I found this 8-foot laminated-beam at a new home construction dumpster in Phoenix. I knew I wanted to use it in a future natural building project. That was 10-years ago. This beam finally found its home as a 'lintel' above a french door type opening in this studio.

To support the beam in place on each side of the opening, two steel 3/4"-pieces of rebar extend-through a drilled hole (of equivalent size) on both ends of the beam. The steel rebar is vertically attached at its base in the stone stem-wall and is further secured inside the cob wall.

Eventually as the earthen walls continue to rise in height, the cob wall and the rebar should provide the stability required for the laminated beam.

Thanks for the help!

2010-01-13T22:11:00.000-08:00

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Arivaca, Arizona is a community of natural builders, organic farmers, artists and people looking to live life their way, as opposed to a conditoned or contrived way of life. The combination of environment and cool people attracts likeminded from all over the world to visit and check it out. Some never leave.

I was fortunate last week to have three visitors looking to learn about cob construction and eager to dive into the mud. From left -to-right in the photo: Christian Douglas, Tonia Sing Chi and Tanya Collings. We had a real good time cobbing and being in the present moment.

Progress Photo

2009-12-07T20:21:00.000-08:00

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I'm learning that the higher up you go (especially up-and-down scaffolding), the slower the progress. However, the work continues!

Lintels for second window

2009-10-17T20:43:00.000-07:00

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As the cob walls reach window height, the 2-foot thick walls require lintels (beams) to span across the window opening. In this photo you can see a concrete lintel above the rough window frame and two mesquite wood lintels.

The bark was removed from the mesquite wood using a 'draw-knife'. Removing bark is hard work. To strip to mesquite beams of bark and cob them in place was a full day's work. However, from the photo you can see the effort was worthwhile. It looks beautiful.

I applied a little wood oil to the exposed wood to provide protection from the elements and reveal the wood grain. After the building is weather-tight and the inside walls have been covered with an earthen plaster, the mesquite-wood beams will be cleaned-up and further protected with additional coats of wood oil.

The Cob Mix

2009-09-15T18:06:00.000-07:00

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"Cob" as a natural building material is a term that most find unfamiliar outside the sustainable building community. Cob is essentially a mix of straw and clay soil. When I use the word 'cob' in this blog I normally provide a link to wikipedia so the reader can get a good definition. Click here to learn more.
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In this entry I'm going to focus on how I make cob and some background on cob as a building material.

I use an 8-horsepower concrete mixer with a 1-cubic yard capacity, instead of hand-mixing. My walls are up to 2-feet thick and I estimate that when completed, I will have applied between 40-50 tons of cob to make the walls of my studio. In order to finish the building in my lifetime, I find the mixer an essential tool to make the 2,000 pounds of cob I can apply to the walls on a productive day of 'cobbing'.

When using a mixer, the batch of cob needs to be wetter than if mixed by hand. This is because if the straw-clay is too dry it will 'ball-up' in the rotating drum and not mix throughly. I usually start with about 15-20 gallons of water, then start the mixer. I throw in about a 14-inch section of straw from a 3-strand straw bale. As the mixer rotates, the straw thouroghly mixes with the water. At that point I begin to shovel in the clay soil. The clay is first sifted through a 1/2" screen to remove rocks and other inclusions.

Note that my soil is almost pure clay and some books recommend adding sand to the mix. This helps keep the clay from developing cracks when drying. I decided that I didn't want to have to haul in sand for this project, so what I did to compensate for the lack of sand was add more straw to the mix. I'm finding that this works fine with very little cracking in my walls to date.

I continue to shovel in clay soil into the mixer until the batch looks like this composition (consistency) as shown in the above photo.

I call 'cob' natures fiberglass. The interlocking fibers of straw in a clay emulsion are similiar to glass fibers in an epoxy polymer (fiberglass). Two feet thick of cob provides a high-strength monolithic wall, that is both a structural (weight supporting) and a thermal mass system to mitigate large swings in outside air temperature, thus keeping a structure comfortable and/or requiring very little heating in the winter and cooling in the summer.

A Dry, Hot Summer

2009-09-07T23:22:00.000-07:00

The upside of a disappointing summer monsoon season was suppose to be more time spent applying cob to the walls of the studio and less time dealing with muddy ground and erosion. However; record heat, vacation travel and other work reduced the amount of hours dedicated to the studio. Now that September has arrived, the tail end of the real hot weather has only about 3-4 weeks remaining. I'm looking forward to the cooler weather.
Photo: Peggy Santello

Mesquite Wood Lintels

2009-08-10T11:22:00.000-07:00

With a wall thickness of the studio up to 2-feet in width, I wanted to utilize another local resource, 'Mesquite', to span and support loads above each window opening. Prior to the addition of the Mesquite wood, the previous blog (see the July 15 entry) documented the first step of casting a concrete lintel above the rough window frame. Visible in the photo below, the face of the concrete lintel will eventually be finished with an artistic ceramic tile design.

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The first step was to cut 36-inch lengths of mesquite from trees on my property. Mesquite is prevalent in the Arivaca area and selectively cutting branches from various trees ensures the sustainability of this renewable resource.

The next step is to strip the bark off the logs using a 'draw-knife' (shown in the photo at right). The photo shows the progression until the log is stripped bare of bark, sanded and coated with Tung Oil.

The close up photo (left) shows the beauty of mesquite and the richness of the wood grain brought-out by application of the Tung Oil.

Mesquite wood is extremely dense, strong and durable; thus ideal for this structural application. In addition, its striking beauty and a local (southwestern) resource makes it ideal in any natural building aesthetic.

The process is a lot of hard labor. It took two days to cut, prepare and 'cob' in the wall these four mesquite lintels.

Other uses for Mesquite include harvesting pods as a food resource and exquisite furniture made right here in Arivaca.

Cast-In-Place Lintel

2009-07-15T18:31:00.000-07:00

A 'Lintel' is a beam that spans an unsupported space (like a door, passage-way, or, window in this case). The purpose for the lintel is to prevent compromising of the wall, as forces resulting from the weight of the adobe wall above the window frame, press downwards on the fragile frame and window.

Traditionally, adobe homes used wood lintels. However, today the building codes in your area may not allow wood lintels, specifying a concrete or steel beam instead. The code has concern that wood lintels may decay over time due to weather or bug infestation.

As a result, my solution is to provide for both strength and aesthetic by casting in place a concrete beam and later bolting a mesquite wood face plate. See photo example of the finished wood facing and trim in an adobe out-building I constructed a few years back (below).

In the picture above, you can see I scuplted the 'cob' walls on each side of the window so they can be filled with concete and span the window opening. I used two pieces of vertical rebar that were placed when the stone stem wall was being constructed, to secure a horizontal piece of rebar as reinforcent of the lintel. The lintel is 4"-high and 5"-wide and spans the cob wall about 12" in each side of the window. Note that I made cob walls at the base (of the form), about 3/4" higher than the top of the window frame. That way, the poured concrete in the form will not be directly resting on the window frame, thus defeating the purpose of the support in the first place. To account for the 3/4" gap above the wood frame, I cut a strip of insulating foam board (see photo above and below). The concrete will rest on the foam instead.

In the photo to left, observe one of the two anchor bolts I added. The threadede end extends through the wood form. These bolts will 'anchor' the mesquite wood face plate that will be added later as a finishing touch along with the trim.

The photo below shows the poured concrete lintel with the wood form removed. Notice the two anchor bolts and foam between the lintel and the wood window frame. The rocks embedded in the concrete on top of the lintel will give the 'cob' that will be placed on top of the lintel something to grab onto.

You may have noticed that the width of the lintel does not cover the approximate 2-foot width of the massive cob wall; only the width of the window frame. I need to address this and will present a solution in a future blog entry.

Photo at right show an example of the mesquite wood face-plate and trim on another finished adobe I completed (click on photo to enlarge for a better view).

Progress Photo

2009-06-18T16:10:00.001-07:00

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West Wall Reaching Ceiling Height

2009-06-15T15:57:00.000-07:00

A portion of the west wall has reached ceiling height (9ft). Remember that from this view, the wall is partially 'bermed'; therefore, on the inside at floor level this room is essentially below ground.

If you look carefully you can see a string along the top - set with a line level - that's the final height I'm working toward.

Also in the photo at right, there is a 'form' set up to eventually pour a concrete 'lintel' above the window. More on that in a future post.

Adobe Brick Wall

2009-06-13T15:38:00.000-07:00

As part of the architectual look of the studio, I wanted to create the effect of a newer earthen building built on top of an old adobe 'ruin'. Therefore I'm constructing two partial adobe brick walls on each side of a doorway in the studio

I had about 110 of these adobe bricks left over from another project and decided to integrate them into the building design. The adobe bricks are made with 40% clay and 60% sand (unstabilized). You may be able to tell from the picture (click on photo to enlarge), that I applied a clay coating over the bricks to help protect them from the expected summer rains.

You can see this wall in context to the whole structure in other posts to this blog.

Honeycomb Calcite Lighting Effect

2009-06-02T14:08:00.000-07:00

The photo below shows a portion of the bermed west wall above ground level. The wall height at this section of the building is nearing completion. The glass block window allows afternoon light to enter a 'mirrored' rectangular chamber in the 2-foot thick wall before stiking a translucent Honeycomb Calcite stone positioned on the inside wall (see other photos below).The photo to the left shows the Honeycomb Calcite stone in the interior of the 10-foot diameter "Kiva" room of the studio.

A close-up photo (right) reveals the beautiful orange-yellow color of the stone. Once the room is completed, light entering from the western sky will illuminate the stone to produce a striking glow in the room.

Cob Progress Photos

2009-05-19T18:27:00.000-07:00

Despite 95-deg F temperatures here in Arizona, 'cobbing' continues at a relentless pace. I'm able to set and sculpt about 5-wheel barrows of cob a day. Each wheel barrow load is about 200-lbs, so that's about 1/2 ton. Therefore, 20-days work so far is about 10-ton of cob in the walls.

As you can see from the above photo, the walls are massive; 2-feet thick or more. Since I'm not using any sand in my cob mix, I'm adding extra straw to prevent cracks from forming. So far no problems. The lone wall with adobe block (see earlier blog) is looking cool!

Cob Progress

2009-05-19T18:25:00.001-07:00

Styling with Adobe Block

2009-04-14T23:41:00.000-07:00

The doorway show on the left will have adobe blocks that, when finished, will stair-step down away from the doorway creating the feeling of an old 'ruin'. The effect in the architecture of the structure will be that of a newer cob building, built over 'ruin' of an old adobe block building.

The idea to use adobe block in the cob building came from knowing that I had adobe bricks on site since the year 2000, the year the out-building (pump house) was constructed.

I wanted to use materials already on hand in construction of the studio, so I had a creative challenge to design those adobes into this cob building aestheticly.

All these years since 2000, approximately 120 adobes were left over and kept under protective wrap - waiting for a suitable application. That time has come.

Cob Walls Start to Rise

2009-04-01T22:01:00.000-07:00

Finally, after a few years of meticulous work on the stone stem walls, cob is being applied to those walls.

My soil is extreme clay and I'm using this same soil for the walls. What's cool is that i'm using the same soil removed during the excavation of the hillside; that this studio is now bermed (see earlier blogs).

So the excavated clay soil becomes a 'local' resource used in making all the walls. If you include the cost of the excavation, and the straw used with the clay to make the 'cob', it's about $1,000 in primary materials. With that you get all the structural walls that also act as a thermal mass system. So the design of thermal mass in this structure, gets me a free heating and cooling system by utilizing the daily temperature cycles that make up a desert climate. This is how to extremely leverage $1,000 into the substantive basis for a comfortable and sustainable living environment.

Machine & Materials

2009-03-18T23:07:00.000-07:00

Both placement of the clay screening area and the mixer were considered in relation to the distance the wheel barrow loaded with 'cob' would need to be hauled to the wall locations.

Some readers of this blog may object to the use of a gasoline powered machine in the construction of a 'natural' building. I can appreciate that thinking. From my perspective, the machine will assist in getting the building done and put to productive use sooner. Especially since this building will be my office and creative project space. Nothing can be more important for me now, then that space.

Nature's Stained-Glass Window

2008-10-27T20:55:00.000-07:00

As preparation continues to begin the cob walls, I needed to prepared a large Honeycomb Calcite stone slab for placement placement in the east wall.

The stone needed polishing on the flat surface side (shown in photo), that will be facing toward the interior of the room.

The opposite side of this stone is the original outer surface, which is right now a frosty-white. Later I will sand-blast the outer surface of the stone to remove some of the stone's 'skin'. That will allow more light through, enhance its translucency and thus create the stained-glass window effect.

Cob Preparation Project for a Sunday Afternoon

2008-09-30T23:23:00.000-07:00

Fastening A Window - Preparing for Cob

This is a window I'm adding on the northeast facing curve in the wall. I wanted this window up-high, so to provide cross-ventilation for the large room of the studio space.

I'm using rebar, coming-up from the stone stem wall, to provide support for the window (frame). I used a section of bamboo, secured to the the rebar, as the securing base of the frame. The top of the window frame is level with the top of the door frame, just next to it.

Click on photo for an enlarged view

I have anchor bolts extending-out from the frame (in photo shown coming out from either side of the frame). These anchor bolts, along with the bamboo and vertical rebar supports, will all be "cobbed-over" eventually. "A support within a support" So-to-speak.

Window Sills

2008-06-18T05:15:00.001-07:00

With a stem-wall height of approximately 3-feet, the rough frames for the south facing windows are essentially just above the wall height. See photo to left (before shot).

Anchor bolts were cemented into the top of the stone wall to secure the rough window frames to the wall. I decided that instead of simply cobbing under the windows and plastering (a potential future maintenance hassle), that I would just continue the stone masonry up to the bottom of the window frame, creating a attractive and maintenance-free surface.

I use old bicycle tire tubes stapled to the bottom of the window frames (not shown) to create a 'seal' between the stone and the frame. This keeps water from leaking in from the sill.
The photo above shows completion of the first sill (inside looking out). The sill on the outside will slope slightly down in order to keep rain from pooling and working its way under the sill.

Smaller flat rocks were collected for this phase of the building project. I initially thought this part of the stone work would be a real pain; but seeing how the sills add a finished look to the stonework and the creative aspects of fitting stone, is making this task quite rewarding.

(Note: Click on any photo in this blog to enlarge)

Retaining Wall

2008-03-18T04:46:00.000-07:00

The stone retaining wall for the western berm was recently completed. It rises to 8-feet high, which is about 1-2 feet higher than the earth on the western side of the studio building.

Eventually, the wall will be extended further (north) along the excavation to become the western wall for new (future) buildings.

For now, the wall was constructed to this size in order to protect the studio from a possible cave-in of the earthen berm during heavy summer monsoon rains.

The area between the retaining wall an the studio as shown in the photo will remain outdoors as part of the 'hacienda' concept envisioned for the several additional living structures planned for this overall design.

The second photo shown here is a close-up of the wall showing details of the stone masonry.

As with the rest of the studio stem-walls. All stone has been obtained locally in dry washes and nearby mountains.

After two years, the stone work is wrapping up. There still are some finishing touches before the 'cobbing' will begin.

Backfill of West Wall

2008-01-12T12:08:00.000-08:00

Preparation for cobbing continues. By backfilling the west wall, accessibility is now improved.

Due to high clay content of my soil, I've found it practical to lay-down about an 1-inch thick layer of gravel to not only keep erosion from rain water in check and make walking and hauling materials easier around the structure. Also, the gravel helps but keep mud off shoes after rains.

The gravel was shoveled and hauled by pickup from a nearby dry-wash. It's hard to tell from the photo, but the 'pitch' of the backfill is such to move water away from the buildings toward the mesquite trees just to the south.

Honeycomb Calcite for Cob Wall

2007-12-08T14:58:00.000-08:00

I plan to place in my cob walls, a beautiful translucent orange-golden colored stone called Honeycomb Calcite. The stone is quarried in northeast Utah as boulders, then cut into slabs, cored to make cylinders or scuplted into various shapes. Over the past 7-years I have been selling this stone as a side business after incorporating small slab in the wall of an adobe building I completed (see Adobe Out-Building).

You can see from the photos in the link for the adobe out-building, the stained-glass effect with the stone placed in the wall is fantastic. After the adobe out-bulding was completed, I fell in love with the stone and I now plan to use it in all my natural buildings.

The slabs shown in the photo above weigh up to 200 pounds. They have not yet been polished to bring out the full color and texture. Only one or two will be placed in the studio walls, the others will be sold to artists, sculptors, and other natural builders.

I need to select the Honeycomb Calcite slabs I will use in my studio before I begin the cob, so I can devise a mounting method to insert the slab and build the cob wall around the stone. Stay tuned to this blog as building progresses.

Solar-Gain Room Stem-Wall Completed

2007-11-02T17:17:00.001-07:00

Work on the solar gain room stem wall is now complete. The wall looks taller than adjacent walls because the grade of the land slopes southward. However the interior wall height will be about 2-1/2 feet high from the finished floor level (you can see a small 'stake' on the above photo - right side of photo - that was set in with a surveyor's level at what will be the finished floor height).

Solar Gain Room

2007-09-17T17:19:00.000-07:00

The stem wall being constructed here is for an area that I'm calling the "solar gain" room. Facing south, there will be large windows on three sides and a stone floor to absorb solar radiation during the winter months. Once the building is complete a french door separating the solar gain room and the studio, could be openend to allow heat to enter the main studio space. At night, the french doors can be closed and the solar gain room will act as an additional insulating buffer from winter nights that temporarily get down into the 20's and low 30's.

The reason why the stem wall for this room was not completed earlier was to facilitate construction access. This room is a bulge on the south side of the building. If this area was constructed earlier, access to the south & north side of the studio for hauling rock and other material would have been difficult. Trees, cactus, yucca and the grade of the land make access to the south side very tight. Now that the stem walls for the entire studio are essentially complete, construction of the solar gain room has begun.

Technical notes: The stem wall, like the rest of the studio rests on an 18-inch deep rubble trench footing (filed with 1"-3" dia river rock). However, the wall for this area will be only 16"-thick, compared to the rest of the studio where the walls are 2-feet thick.

Stem Wall Progress

2007-09-12T16:26:00.000-07:00

Except for a small 'solar gain' room that will be added to the southeast corner of the studio (top left of photo), the stem wall is almost complete.

The right side of the photo shows the retaining wall buttressing the earth to the west,
sufficiently completed. But as time allows, that wall will be extended to eventually form the basis for new buildings.

Room Passage Completed

2007-09-10T16:37:00.000-07:00

These photos show two views of the newly completed stem-wall section for what will be an Anasazi-style archway between the two main rooms of the studio (See Anazasi Arch entry for a historical view of how this passage will look completed.)

West Wall Above Earth Height

2007-08-28T15:05:00.000-07:00

The west wall of the studio's 'kiva room' is now at sufficient height above the earth berm. Not shown, but extending north (from top-right of photo) is the 8'-high stone wall retaining the earth along the western cut of the excavation. Once a portion of the retaining wall is complete, work will move to completing the 'Anasazi Arch' (see blog archives for discussion) that will connect this room with the larger studio room. And finally, the solar gain room off the southeast side of the studio will be completed in september.

From that point preparation for the 'cob' (straw/clay) walls will begin.

Stem Wall Nearing Completion

2007-06-16T05:17:00.000-07:00

This photo shows an overview of progress on the stone stem wall as of June 12, 2007. The west wall (right side of photo against the berm), has reached to top of ground height. It will need to extend about 18" higher (above ground height), before construction of the earthen walls begin.

The western retaining wall that extends north from the circular room, still has a way to go.

The stem wall for the solar gain room on the south side of the structure (top-left in photo), will be completed last, so not to impede easy movement of stone and material needed to complete the stone work on the west side of the studio.

With the summer monsoon season on its way soon, the studio is ready to take-on the expected heavy rains!

Backfill

2007-06-01T16:12:00.001-07:00

Following the application of at least 12" of gravel over the drain pipe, 6-mil plastic was laid on top of the gravel and the entire disturbed area was backfilled. To facilitate water drainage away from the stem wall, the soil was graded to slope away from the building. As the backfill was in progress, a tamper was used to compact the soil to help prevent settling (although some settling is expected).

Once the backfill was complete, about 1" of sandy gravel was added to the disturbed area. This was for practical reasons. The gravel will help: 1) Keep dust from kicking-up during high winds. 2) Keep excessive mud off boots during the upcoming summer monsoon season. 3) Reduce soil erosion during rain.

Completion of the backfill will improve building productivity because the stem-wall on the west side (the berm side), was getting too high to reach. Also, working in the narrow confines between the earthen berm and the stem wall was a safety issue (cave-in, trip/fall).

Footing Drains

2007-05-30T19:16:00.000-07:00

My desert location receives approximately 15-18" of rain per year (if we're lucky!). In the summer monsoon season, heavy rain falls during thunder-showers. The key to keeping water away from the studio will eventually be proper finished grading of the soil, in order to slope away from the stone walls.

This location does not have issues with waterlogged soil like other parts of the country; where collected water between the foundation wall and the soil is subject to kind of a hydraulic pressure that in effect, forces the water through cracks in porous foundation walls. However, even in the dry desert, building codes and good practice recommends installing a provision for water removal around the footings/foundation of most structures This prevents water from seeping through walls into living areas and water saturated soil from undermining the structural integrity of the footing/foundation.

The first step was to waterproof the stone wall that will be buried in the berm. I decided to try an elastomer (rubberized) roof coating. I applied two coats (fill & finish). In the old days, I used 'tar' to waterproof foundations, but I'm trying to avoid petroleum products in this structure; and also, tar is very messy. Will the elastomer coating work for the long haul? I don't know, but the instructions said it can be applied to stone & masonry. It has a 10-year rating for roofs; and the coating won't be subject to UV sun damage as it will be buried in the ground.

As the photo above shows, the ground was leveled and on it was placed a 6-mil plastic ground sheet to prevent the clay soil base from clogging the pipe. The plastic pipe is perforated, and the holes were placed down to draw-in any water collecting on the plastic. The pipe was leveled. To get around the circular shape of the building I used 45-deg elbows and connected short sections of pipe (as illustrated in the photo).

The photo to the right is kind of a cross-section of the footing drain project, showing gravel around and on top of the pipe, followed by a top sheet of plastic to keep the clay soil that will be used for back-fill, from working its way down into the gravel over time and clogging pipe (click photo to enlarge).

Also in the photo you can see rigid foam insulation (R2.9), applied against the stone stem-wall. This insulation will provide a thermal break between the earth berm and the building.

Provision For Electrical

2007-05-06T09:50:00.000-07:00

All electric lines were embedded in the stone stem wall. Outdoor direct burial #10-wire (30-amp capacity) was used. Placing electrical boxes in a stone wall was a challenge; but the height of the wall (2-1/2' - 4' tall) necessitated such placements.

Also notice on the right side of the photo, a piece of plastic electrical conduit (capped). This conduit extends through the wall on the south-side of the building, for the purpose of future telecommunications hookups or antennas.

The five electrical circuits terminate in the future solar equipment/battery room.

Not shown are two (2) additional underground conduits; installed with the purpose of providing electricity to future adobe buildings that will compliment the studio as part of this hacienda-style site layout.

Rebar & Bamboo

2007-05-06T09:02:00.000-07:00

In order to help secure the forthcoming cob walls to the stone stem wall, vertical rebar was placed in the stem-wall during construction of the wall. Lateral support was provided by the use of bamboo poles. Bamboo is both a strong, renewable natural resource; and was provided by a local grower. For curved corners, short pieces of rebar were hand-bent and secured to the vertical rebar using wire.

Also note that the stone stem wall is concave at the top so that the cob mix will 'key' into the wall for additional lateral stability.

First Quarter Progress

2007-05-05T01:27:00.000-07:00

Progress photo taken at the beginning of April 2007. Note on far front-right of photo, the stone retaining wall that will rise 6'-7' high on the west side. The area just to the left (east) of the retaining wall will be an open-air area of the hacienda, providing needed afternoon shade for sitting outside.

The only wall construction remaining is the retaining wall and the west side of the kiva-library room (top-right of photo).

Kiva Room

2007-05-02T10:42:00.000-07:00

This photo looks west from the main studio area into the kiva library. Notice that on the left side of the photo the pass-through wall height is complete; but the right side is not. This is for practical reasons: If the right-side pass-though wall was completed, I would not be able to get a wheelbarrow through!

Also, from the top of the photo, you can see the earth that the structure will be bearmed against. The stem wall on the west side of this room will need to rise at least 12-18" above the berm, before it is complete.

Year End Progress

2006-12-28T14:28:00.000-08:00

As 2006 draws to a close, I wanted to post this photo as a snapshot of where I'm at to this point.

There is still a lot of stonework to do, but my calculations show that I was masoned 35-tons of stone so far. This figure includes the stone, sand, gravel, slaked lime and Portland cement.

I estimate that the stone stem wall will use 50-tons of material before its complete, and I then can begin the adobe (cob) walls that will define the stucture.

My back is doing fine :) Happy New Year!

The Stone Pit

2006-12-20T14:16:00.000-08:00

Work continues on the studio. Now winter time is here and like the summer, productivity is impacted. Due to the 3,650-foot elevation of this site in Arivaca, night time temperatures dip regularly into the 20's if not the teens. Water hoses freeze, days are short, and who wants to get out of bed into that cold anyway?

But work presses on and 2007 offers the opportunity to continue this giant stone sculpture, that will eventually become my art studio.

Rough Openings

2006-10-25T13:20:00.000-07:00

In order to secure rough door openings to the walls, I first used my builder's level to set concrete pavers in cement at the height of the finished floor. The rough 2"x6" door bucks were then set on top of the pavers, leveled and plumbed into position. The rough door openings were fabricated to the outside dimensions of doors already purchased for this project. Rough openings are made at minimum 1/2-inch bigger on all sides to allow for the finished door to fit the rough opening and for shims necessary to level the door in place.

In order to secure the rough door buck into the stone, I drilled a hole in the wood - the diameter of the bolt - and inserted the 8"anchor bolt (see above photo). Also notice in the top-left photo of the collage, that I counter-drilled a larger diameter hole that does not go all the way through. This allows for a large washer, nut and leaves room for a 3/4" socket to be inserted to secure the nut. The nut is secured once the entension part of the anchor bolt is cemented into the stone wall against the door frame.

The bottom-right photo in the collage shows the finished wall build around the the rough door buck. Two additional anchor bolts will be placed vertically, on each side of the frame of the rough buck, as the cob is applied to the wall on top of the stone stem wall.

Anasazi Arch

2006-09-28T12:51:00.000-07:00

During my travels to Chaco Canyon and other Anasazi ruins throughout the Four-Corners area of the southwest, I noticed in several locations the design of what I call the "Anasazi Arch" (see photo to right). It's essentially a "T"-shaped passage between rooms. In the case of this photo the passage leads from a room into a ceremonial room of the great Kiva known as "Casa Rinconada" at Chaco Canyon, New Mexico.

I plan to incorporate an "Anasazi Arch" that will connect my studio work room with the library room.

The photo to the right shows the begining of the "Anasazi Arch" in the studio with a view looking toward the main studio room behind me.

The stone work is in its early stages, but the right side of the passage shows the detail work to this point.

Taking Shape

2006-08-28T12:24:00.000-07:00

The photo shows progress after a couple of months of work. Summer heat and monsoon rains effected productivity for obvious reasons.

If you look closely at the ground in the photo you can see the ground in and around the studio with a layer of gravel. In order that I could work after rainstorms without my feet getting stuck in the clay mud. I made six trips to a nearby dry-wash and filled the bed of my truck gray-colored gravel.

With regards to the summer heat, there was nothing I could do about that :)

3-Dimensional Jigsaw Puzzle

2006-07-20T11:43:00.000-07:00

I'm learning as I go, but one thing is for sure, these stem walls are solid and look great. As the walls rise out of the ground, there is an artistry that emerges and your building feels like a giant sculpture.

Some of my natural bulding friends have asked me when will I stop with the stone wall and begin the earthen 'cob' phase of the building process.

My answer to that question relates both to structure and aesthetic design. The stone-footing at minimum, needs to support the massive adobe (cob) walls that will rest on it. In addition, the west side of the studio that will be bermed into the hillside, needs to be all stone until it reaches a height at least one foot to 18-inches above ground level. This will keep the splash of rain hitting the ground from hitting the earthen wall (that will eventually be lime plastered). Also, the stone stem-wall will deter termites from gaining access to the earthen walls.

Finally, the transition from stone to the earthen wall will achieve a significant visual aesthetic for the structure. An example, would be the straw bale house of a friend in Alamos, Mexico, where the stone stem-wall concept was employed. (see photo to above).

The difference in my design besides the use of 'cob' instead of straw bale, will be that the height of my stem-wall will vary along the course of the structure - like the rolling hills of my surrounding landscape.

Progress Photo

2006-06-29T14:44:00.000-07:00

Stone Stem Wall

2006-06-15T10:24:00.000-07:00

Using locally sourced stone pulled from nearby mountains and dry river beds, two-foot wide masoned stem walls have begun to rise from the top of the rubble trench footing. My technique is to place and mortar stone along the inside and outside of the trench and then 'infill' with additional rock and mortar, thus tying together both sides of the wall.

I am planning to lay a first course around the perimeter of the studio and then work vertical from there.

Rubble Trench Footing

2006-06-12T17:33:00.000-07:00

The "floating footing" or "rubble-trench footing" is an alternate approach to a building's base foundation for heavy clay soils, as opposed to simply pouring concrete into a footing trench. Clay soils are expansive and when wet could possibly put a lateral stress, or cause heaving to, a standard poured concrete footing.

In the concept of the 'floating footing', the typical 'in-ground' concrete footing is replaced by 1"-3" (rounded) river rock. The footing channel for my building, is 18"-deep and 2-foot wide. The footing was hand dug and a surveyor's level was used to ensure a slight pitch for drainage of the footing, leading to a pipe at the southeast corner of the building. The channel was lined with heavy-duty plastic to facilitate water drainage and keep the ground directly under the floating footing from getting saturated during heavy rains.

The river rock was compacted with a tamper and eventually brought up to grade level. On top of the floating footing will be a massive 2-foot wide 'stem-wall', made of large stone masonry. In most places this wall will be 2-foot wide.

I have been curious to employ this method ever since I heard Frank Lloyd Wright used a floating-footing for construction of the Imperial Hotel in Japan in 1916. This building subsequently survived a severe earthquake without major damage. The theory is that since the building rests on the surface (on top of the rubble filled trench), when an eathquake stikes, the rubble-trench slides under the building when subject to the lateral force of the earthquake.

The foundation of a building is critical to maintaining the integrity of the structure. It needs to be strong and the appropriate size for the building so the structure won't settle, buckle, or spread apart. Please note that the "floating footing" system is somewhat experimental and not appropriate for sandy soils or sloping terrain that can be eroded to the point where the rubble-filled trench would be exposed and compromised. Consult an soils/structural engineer if necessary for your project.

Provisions For Solar Electric

2006-06-08T11:06:00.000-07:00

Doing the grunt work early on makes the project go smoothly and the finished building look well planned and designed. The time to lay in utilities (water, gas, waste water, electric, phone serivce, etc) is when you're doing the footing/foundation. Neglecting the proper installation of these essential services now, means later you will be drilling through finished walls, have exposed pipe & wires to the weather and UV damage; not to mention it will just be ugly.

In the case of my art studio, I will only be using electricity. However, I plan to 'rough-in' black pipe for supplemental propane heat if the bulding's thermal performance upon completion requires it. I also provided conduit for phone or antenne lines if wireless options are not available.

The photo shows 2"-gray electrical conduit extending down the exposed excavation to what will be the utility room of the studio. This conduit will contain the main DC electric load wires from the solar photovoltaic system that will be installed later, on the elevated land to the west of the studio. Not shown are two additional underground conduits that will someday bring electricity to other small ancillary buildings (not yet constructed) that will be adjacent to the studio to complete the hacienda-style layout of the studio compound.

Gravity Drains

2006-06-04T21:38:00.000-07:00

It is critical that rubble-trench footings be properly drained; especially since heavy clay soils are expansive and could put stresses on the footings. Wet clay soils could also result in excessive settling of the structure if not kept dry.

I used a builder's level to pitch piping for a gravity drain to remove any water that could accumulate in the rubble-trench footing. The south sloping land away from the structure provides a natural contour for water removal.

The entire footing trench will be lined with heavy-duty construction grade plastic prior to being filled with 1"-3" rounded river rock.

The studio footing gradually slopes (1" per 7-ft) from the northwest corner toward the southeast corner where the drain pipe is located. Any water drained out the pipe will irrigate a mesquite tree grove on the north side of a dry wash.

Pick & Shovel

2006-05-31T07:58:00.000-07:00

I began work by digging a 2-foot wide, 18-inch deep 'footing' trench, that made up the footprint of my studio design. The compacted heavy clay soil of my land is ideal for digging trenches with firm side-walls. In another building I constructed on my property; I created a concrete footing, simply by digging a trench in the clay, set up reinforcing bar, then poured concrete directly into the ground. No form-work was necessary. This method saved both time and money.

Refering to the photo, the circular room will be the library/office. The large oval room will be the primary creative space for digital-film post production. The rectangular space to the right will contain the batteries & controlling equipment for the building's solar-electric power. A division in the same room will provide storage space for the studio. To get a feel for scale, the building will be approximately 35-feet by 25 -feet in size.

Stake In The Ground

2006-05-20T19:01:00.000-07:00

Since it has been about 8-years between the time I purchased my land until I started the studio; I used that period of time to observe the land and plan both the art and the science behind the location of the first structure. I knew once the excavator arrived to clear my building site, there would be no possible way to change my mind regarding placement of the cob studio.

My cob art studio will be the first of several solar-powered earthen dwellings, making-up a hacienda-style placement of living/workng environments.

The photo in this blog shows the completed excavation for the studio. I chose to locate the studio in a berm for several important reasons: 1) The clay soil excavated will become the primary building material for the structure. 2) The west side of the building will be against the berm, thus keeping the afternoon summer sun from baking that side of the building. 3) All structures built in the mound will seem to blend into the environment, as opposed to sitting directly on top of the land and sticking-out like a sore thumb. 4) Sounds that seem to travel unobstructed over long distances in the desert, will now pass over top of the buildings; resulting in quieter living/working environment. 5) I will just look cool.

The photo in this blog shows the completed excavation. The left side of the photo is south; the right side of the photo is the north side. The excavated profile of the land running across the photo is the west side and has an elevation of approximately 9-feet at its peak height. My cob studio will incorporate a passive-solar design; with a majority of the windows facing south in order to optimize solar heat gain in the winter. Most bermed buildings have their north side against the earth. However; since the earthen mound on my property runs north-to-south for approximately 100-feet, I decided that the summer sun in the west would be more of a challenge to creating a comfortable living space than the potential cold of the north side: Therefore, I will be 'berming' the west side of the studio.

Since I'm starting out with the studio at the south end of the mound, the current idea is that the north side of the building begins the courtyard. the courtyard will extend towards the north until the next series of structures is built.

Local Resourses

2006-03-25T17:32:00.000-08:00

When I was in the process of chosing a land for my art studio, the availability of natural building materials on or near the site was an important consideration in the purchase. As the photo shows (starting at the top-left clockwise); the land I selected, has many small rocks on the surface that I use for a variety of purposes: Gravel fill, drainage channels, aggregate for concrete, pathways, etc. Testing the soil revealed ample clay - ideal for making adobe, cob and earthen plasters. The piled stones in the second picture were culled from mountain washes on nearby federal land; and used for the construction of stem-wall footings. A heavy metal screen for sifting clay and river sand was purchased from a local metal dealer, who obtained the heavy steel mats from an old mining operation in the area. The last photo shows a dry wash on my property where sand for application in cement mixes, lime plasters and other building uses is obtained. Flash-flooding that occurs each rainy season, replenishes the sand, creating naturally occuring sustainable resource.

The use of local resourses for natural building materials not only saves money, but reduces planet energy consumption associated with the use of excavation/loading equipment, rock crushers, and trucking materials long distances to the project site.

Image for Design

2006-03-15T13:10:00.000-08:00

I have spent several years trekking to Anasazi ruins up in the four-corners area of the southwest, looking for design inpsiration for my art studio. However the light-bulb didn't go off until returning a few months back from Chaco Canyon.

On the 6-hour drive back to Arizona - assisted with a cup of hot coffee - I had plenty of time to think and generate ideas from the new information I had gleaned during the trip. I arrived home at 11 p.m. and with work the next morning you would think I would have crashed for the evening; but instead I decided to watch a movie! It was imagery and sound film by Godfrey Reggio called Powaqqatsi (Hopi meaning “Life in Transition”). The film is a montage of images about life in the Southern Hemisphere and how globalization and technology is affecting the hand-made way-of-living for these people.

In one 6-second scene in the film, an aerial fly-over view of a primitive farm in Kenya, Africa is shown (Refer to photo). Hedges in circular and curved-line shaped patterns bordered the farm, houses, outbuildings and animal pens. I was fascinated by the aesthetic quality and ‘organic’ abstract design of this dimensionality. I froze the image on the TV; took a digital picture of the screen; then loaded the image on my computer; traced the hedge outline in PhotoShop; and printed a hardcopy to plan from. Then I went to work at my drafting table with an architect’s scale, and before I knew it I had designed the layout for my studio. It fit the land; it met my space requirements and the design mirrors the architectural style of Anasazi . Most importantly, the layout was ‘buildable’ from a practicable standpoint. It was all there. All the design aspects and aesthetic details I have been struggling with for several years reached convergence and made itself known.

I think back now to the film. What were the odds that year’s ago cinematographer would fly-over a farm in Africa and put it in a film? Then I would see this image on a video and design a house based on the planting of hedges around that farm? In some way it seems random to me and in another way the saying: "Chance favors a prepared mind" seems appropriate. The whole process is like writing a poem.

Ancient Building Technologies

2006-03-07T18:27:00.000-08:00

When first thinking about designing a solar-powered earthen studio for my filmmaking and other multi-media art, I was highly influenced by my visits to Chaco Canyon in New Mexico. I wanted to think like an Anasazi in order to adapt dwellings to what can be harsh climate conditions in the Sonoran desert of Arizona. Although the walls of the buildings at Chaco Canyon are stone, my material will be "Cob" which is a mix of straw and clay soil. However, I plan to build a stone 'stem-wall' out of stone for structural and aesthetic reasons.

Cob lends itself well to building irregular shapes, such as: Circles, Curves, Ovals, etc. I wanted my studio space to have flowing curves and a circular room similar to a ceremonial Kiva. (Photo by Barton Santello: Passage between rooms - Pueblo Bonito, Chaco Canyon)

The Man Behind The Plan

2006-03-01T13:10:00.000-08:00