Cob Roof - South Room Progress

I plan to post a more detailed account the roof assembly once I decide on the water-proofing membrane and complete the work. In the meantime, I am providing this status photo to document where am at this moment.

The photo shows that the roof has been covered with a layer of cob. However; note that for this (roof) mix I used significantly less clay...so that after the water evaporates from the mix, the cob will be lighter.  The light mix mitigates weight as an issue for the supporting roof beams (Vigas).

The photo also shows that the surrounding parapet walls are taking shape but are still about a 12-inches from their final height.  I use my regular (heavier) cob mix for the parapet walls.

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Also, additional cob will need to be added to the roof to provide sufficient slope and contour to allow the water to flow out the drain pipe at the SE corner of the roof.

Here is recap of the built-up roof material used to date: 1) Ponderosa Pine beams (vigas).  2) Bamboo latillas.  3) burlap on top of the bamboo.  4) 2"-Rigid foam insulation.  5) 6-Mil plastic.   6) Light clay/straw cob mix.

Mesquite Base for Mounting Speakers

Speaker wire was run through the cob as the walls were being built (see earlier post HERE).  Using a surveyor's level, I marked 10-ft wall height at four locations on rebar equally spaced around the large oval room.

 

I cut a log of mesquite wood into four pieces and drilled a hole through the center of each piece so the wire can extend out.  But the main reason for using the mesquite is that the wood will provide a strong anchor for the large 1978-vintage Genesis I Physics Speakers that I had restored to provide an analogue warmth to music and other audio to this earthen room.

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Bamboo Ceiling for South Room

A bamboo ceiling was created for the south room (below) using the two large vigas shown in the bottom photo to support the bamboo poles across the span.  The term used historically and today in the natural building community for this cross support is "latilla".

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The bamboo poles were precut to length and holes drilled at the proper spacing between the vigas to help speed the installation once on the roof.  The bamboo poles were secured into the vigas by 4"-exterior deck screws and 1"-washers.  The washers helped spread the clamping force of the screw on the bamboo; and the pre-drilled holes helped prevent cracking and splitting of the dry bamboo.

When the bamboo poles were laid-down, careful attention was paid to select a pole whose orientation would provide a 'crown' for better load distribution and in addition; each pole was selected to best match the pole laid-down before it so the gaps between poles would be minimized.

 

Preparation of the bamboo involved cleaning the poles with an abrasive sponge soaked with a mixture of water, bleach and a mild cleaning powder.  The mix of cleaners was necessary because the poles were under tarps for several years and showed signs of mold. 

 

Another major issue was evidenced in some bamboo holes by tiny holes that meant 'powderpost-beatles' were present.  Over time an infestation of these tiny mite-like bugs, can turn these poles into powder.  In order to ensure the beatles would not (further) harm the good bamboo poles, they were all treated with an insecticide, then wrapped in plastic overnight.  Note that 'Borax' will kill these beatles but I was unable to locate borax in time, so I went with the insecticide.

 

Finally the poles were coated with a wood perservative and waterproofing sealer that helped bring out the grain and color characteristics of each pole (see above photo).

 

The vigas and latillas are just the start of the roof structure.  In the coming weeks, this blog will detail the buildup of the roof from this point forward.

End of 2012 Status Photos

Status photos as of December 31, 2012...

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Progress on the roof for the southeast room (below).  Each room will have its own roof level and design.  Cob has built up since the previous blog entry and Latillas can now be laid across the Ponderosa Pine beams.

Beams for South Room

A milestone in any building project is reaching the roof. But building a roof is complicated and challenging. My approach here is to make the process manageable by dividing the roof into four separate projects. Each roof line will be at a different level (height).

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In the photo, two 10-inch diameter Ponderosa Pine beams 10-feet in length were laid on top of the concrete bond beam of the small 6-ft x 8-ft (south-facing) room and secured by metal straps that are anchored into the bond beam. The beams rest on and extend 12-inches on the bond beam as a best practice approach.

The cob mix (clay/straw) is now being built-up around the walls and in future blog posts I will show how I plan to use bamboo as 'latillas' across the beams to create the basis of the rood deck.

Bond Beam Poured for Dome

After completing the Rebar structure that will reinforce a cob dome, the concrete bond beam was poured at the base to support and distribute the weight of the dome.  

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In order to "tie-in" the dome Rebar structure to the building's cob wall, horizontal Rebar laid into the channel in which the bond beam was poured.  Vertical Rebar originating from the stone stem wall, was also tied into bond beam completing the connection from stem wall to dome.

Initial Dome Framework Emerges

I recently changed my original plan of a flat roof for the kiva room to reflect what I originally wanted to do. This circular room was at first envisioned for a dome when the rock stem wall was constructed. However, since the building's architecture was derived from Anasazi buildings at Chaco Canyon in New Mexico, I changed my mind a planned a flat roof to keep the building's design consistent.

Then with work on the roof structure of the studio commencing; I changed my mind back to a dome for several reasons. First, having studied in the past dome architecture from Egyptian architect Hassan Fathy and Iranian architect Nadar Khalili, it's an asethic that I really found appealing in adobe buildings. Secondly, I wanted the challenge of constructing the dome. And third, I decided that my building process is better suited to reflect an amalgam of architectural styles in order to create something unique and original from a design standpoint.

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The picture above represents the initial rebar framework. More framework still needs to be fabricated but I wanted to get the rebar installed before pouring the concrete bond-beam that will support the weight of the dome on the existing cob walls. Thus the rebar frame will be locked into the bond-beam.

The dome itself will be made from cob also with lime-plaster exterior finish. The parabola shape of the dome will make it self-supporting with the rebar frame acting as a safety factor for support, seismic stability and as a guide when lay-up the cob on the walls.

Stay tuned!

Summer Monsoon Stalls Progress

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I was hoping to pour another bond-beam before the summer monsoon rains started (usually around the end of the first week in July). But by that time I already had 4-inches of water recorded from the rain gauge.

As shown in the photo, there were a couple of inches of standing water due to the dense clay soil. The clay is good for making adobe but not for absorbing water! Clay on your shoes can be very 'slick', so waking about the building site and climbing latters and scaffolding can invite injury.

Lightning also accompanies these monsoon storms, so working on scaffolding with steel rebar sticking-up into the air all around seems like an invitation for an electrical strike. So when I see the storms starting to roll in, I pack up the tools and head indoors.

So until things dry out, I'm doing mostly maintenance tasks around the property. Stay tuned!

Second Bond Beam Poured

The second bond-beam was poured over the weekend for the north side 'oval room'. Since each room of the structure will be at a different wall height, the bond beams are being poured separately. The four separate bond-beam pours serve a practical purpose - making it manageable for a lone builder like myself.  The example below is what myself and a helper can do in 4-1/2 hours in 95-degree heat desert sun.  That's how this building is getting done - in manageable and practical building tasks.

The pouring of a bond beam on adobe is a creative challenge.  For the curved walls I'm using Masonite board cut in strips which serve as the form.  Held in place by 4"-deck screws and spaced vertical 1"x2" supports (see photo).  Amazingly, the 'cob' (staw/clay) adobe walls hold those screws rock-solid.

The metal straps sticking-out of the concrete will help secure the Ponderosa Pine vigas (beams) that will support the roof.

Bond beam on cob wall

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The difference in wall heights for each room, was derived from personal observation of the project's incremental formation.   It's not just the building's architecture that is driving the outcome.  Practical considerations like water drainage and the availability or amount of 'material' resources required to construct the roof.  Or the design may change for one part of the structure building resources lying around that I just want to use up.

The roof is a massive undertaking for an individual.  But designing with these limitations in mind are proving a way to innovate around the problem and that's where a lot of satisfaction from this process is derived.

The result so far has been no major compromises.  Sometimes you learn from the building as it evolves, which way is the path forward.

More Bond Beam Prep

The west-side (Kiva) room has reached ceiling height and preparation work has begun to pour a bond beam. The photo below shows how I discovered that a sheet of inexpensive masonite board, could be cut in strips to act as a form for the eventual pouring of the concrete beam.

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I like Masonite because it has a high strength-to-weight ratio and it's flexible.  And as one can see from the shapes of the rooms in this structure, I need that flexibility to accommodate these irregular shapes.  I hold the masonite in place securing 1"x2" pine strips into the cob with 4"-deck screws (see photo above that shows these vertical strips).   


I cut 12"-wide strips from the 4'x8' sheet of Masonite. Then I drew a line 5" down on each strip to denote the height of the bond beam channel.  The 7" of  board below the line is pressing up again the cob and utilized in holding the cob to the wall.


I'm amazed at how the "cob" wall can hold those screws tight.  I used this 'securing' method in a previous bond beam pour, the result of which can also be found in the top-left portion of the photo. I'm fairly confident I won't have any blowouts in the form when the bond beam is actually poured.  

I still need to install rebar in the channel prior to the pour.
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The outer portion of the form is the rising cob wall.  Notice in the bottom photo a simple measurement  'fixture' I devised to ensure a 12-inches wide channel.  The fixture was moved around the back-face of the inner portion of the Masonite form as cob was applied to the top of this 24"-thick wall and up-against the fixture.

North Room at Roof Height

The photo below shows the north room walls at roof height (for the most part).  The string along the rebar was set with a surveyor's level in order to ensure the wall is completed at a uniform height.  Provision for an outdoor light fixture can be seen at the bottom-left of the photo. 

This strangely shaped room will be divided in half with one section used for storage and the other side will be the 'utility' room for the solar power electronics and the battery bank to store the solar energy.  This section of the room will have its own separate entrance via a small 2-ft wide door (see bottom photo).

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The photo below is a ground view of the same part of the building (north wall shown above.  The entry door to the utility room is clearly visible along with the freshly laid 'cob' along the top.

Southwest View

Below is a status photo of the northeast side of the studio showing the main entrance.  The recently finished wall height can be seen along the north wall (darker wet cob).  The next step will be to set up forms and pour a bond beam by similar method to the small room on the south side of the building (left side of photo).  See bond beam blog entry HERE

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Speaker Wire Routing

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In the photo below, Tonia chisels-out a channel in the cob in order to route speaker wire vertically down the wall.  At the bottom, a hole was drilled through this interior cob wall in order for the wire to emerge in another room on the other side where the audio/visual entertainment components will be placed.

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The photo below shows the completed routing ready to be covered-over by a layer of cob. A further discussion on the speaker wire placement will be forthcoming once the walls in the 'large room' reach 11-feet in height where the speaker wires will emerge for each of the four speakers.

 

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Large Calcite Slab Placed in Kiva Room

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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

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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

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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

 

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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

                                                

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

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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

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?

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

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

"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

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

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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

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

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

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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

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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

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Anasazi Inspired Space

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

 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.