No Driveway

Well our plans for a driveway didn't pan out, although we did make it to the property during the week. I determind True South (TS) as compared to the west edge of the property and found that TS is 6 degrees outside the propertly line from the corner. If you look at the figure to the left, the red line is the true north-south line. So you can see, that the property line is not quite aligned to TS.

In the end, I plan to rotate the house 10 degrees east of TS, which will open us up more to the east, which is where the mountains are. This means that we will be at a 16 degree angle to the property line and a 10 degree angle to TS.

At this point it looks like I will get the foundation ready (1" to 3" rubble in a 24" deep 14" wide trench compacted with each 4" to 6" layer) and then order the Adobe and work to build. If we can have this done by the end of September in 2012, we'd be happy. I will post the plans in a week or so.

Solar Wiring Diagram

I have created a small solar generator. It consists of 3 12v DC deep cycle batteries (90ah each), a 7 amp, 12 v charge controller and 3 15 watt solar panels.

Here are a few things to note. Amp hours denote the amps you can discharge a battery over 20 hours, before you have to charge it. To figure out this out, you divide the amp hours by 20. For instance, a 100 amp hour battery can discharge 5 amps for 20 hours prior to requiring a recharge (20 * 5 = 100). In my case, I have 90ah batteries, so it would be 4.5 amps for 20 hrs. The other thing to remember is, if batteries are in parrallel (negative to negative and positive to positive as shown in diagram) then the amp hours are additive and voltage is constant (12 v, not 36). So in my case, with 3 90ah batteries, I have 270amp hours @ 12v dc, available or 13.5 amps for 20 hours. Unfortunately, I only replace 45 watts of power, so I will probably run out at some point as I need a larger charging system (depending on what I draw off). Since this is only used for a few days a month, this should be fine however. It cost me $500.

A couple points. Since I have a 3000 watt invertor (it can draw up to 30 amps), it is important that the wires used between the batteries themselves, as well as between the batteries and the inverter, are large. In my case I use 2 gauge to the invertor and 00 between the batteries. This will eliminate and voltage sag and ensure that my invertor can function with a large draw. I can successfully start and run a full size normal refridgerator with this system, as well as run a 2hp Bostich air compressor to over 120psi. This will be the system I take to and from Taos, until I have my cabin built. Once built, this system will stay there and be the power system for the cabin.

Taos Here We Come

Well we are heading back out to Taos the week after/of labor day. We will be taking some more photos, cutting the driveway into the property, leveling off a flat spot on the west side of the driveway for a shed/cabin and maybe, digging the holes for the rubble foundation. If I can get the foundation dug, I will be planning to fill with gravel. I have spoken to other contractors and builders in the area and due to the dryness of the climate, I won't need a drain tile in the bottom of the trech. Then, next year, I can place the cinder block grade beam and start setting adobes.

The cabin will be 8x12 on the inside, with the 8' side facing south and the 12' side facing east. The 8' side will have large windows to let the heat / sun in for passive solar heat. We will most likely use an earthen floor. I am still unsure on whether I will heat this via radiant floor heat or whether I will remove that for this small cabin, and simply heat with a ventless propane heater. I guess I have until next year to figure that out.

The other major item needing done with this trip, is for us to determine where true-south really is in comparison to the property lines. This will allow me to orient the buildings on the plot drawings.

Stay tuned.

Solar Works

Well I am here in Kansas City, anxiously awaiting a trip out to New Mexico. I continue to plan and we have decided to Build small cabin / shed first, which will be half the size of the guest house. The plan is start small, work it out, try again a bit larger and fix issues along the way prior to starting on the final home. The cabin will be 8 x 12 feet on the interior. I will use 8" cinder blocks on a base of rubble that is 24" deep. The cinder blocks will have the webbing knocked out with rebar placed in the webbing crevices and cement poured in on top of that. Cheap fast way to build a grade beam. I wouldn't do this on the home, but figure it will work fine for a shed / cabin. Anyway, about the solar.

Since I have a plan, I have been buying a few necessities. I have a solar shower thAt I picked up for $10 and have also created a solar generator, if you will. I have 3, 90 amp hour batteries (12v DC) in parrallel, a 7amp solar charge controller, a 3000 watt (sustained) inverter and a 45 watt solar panel. it just so happens that our power to the home went out for 14hrs on Friday and I ran my big refrigerator for 6 hrs with no real issue.

In case you were wondering,divide your Amp Hour rating by 20, to determine how many amps you can push for 20 hrs prior to needing to recharge (assuming the batteries Re fully charged when you start ). For example, 1 90 amp hour battery can push 4.5 amps for 20 hrs. A 100 watt lightbulb is about 1 amp (120v/100 watts),so I could power that for 80 hours or so.

Since I have 3 90s in parallel, I add my amp hour capacity and my voltage stays @ 12v. So I have 270 amp hours to use. My panels however only replace 45watts, so I will run out at some point depending on my use. I figure this should work for me for 3 day weekends. Have fun. My next investment is a MPPT charge controller that supports 2/24/48v solar front ends and battery backends.

What Type Of Home?

Well I haven't posted in a while as I have been digging in to learn more. I have been following Alyssa's progress (my neighbor about 1/2 mile away) and have seen where she is having some trouble with wall plumb as well as squareness of door and window bucks. Since she has been working on this non-stop since May, it is apparent as well that there is a LOT of labor and time in building an earthbag home, which is something I don't have. Since I can't build it all at once, I need to find a method that will allow me to build, let it set if I need to, and come back and finish. I also want to start small and learn. Based on Alyssa's experience, the amount of labor and time required to build earthbag and the fact that I can't leave it (the bags will rot), I am not going to use earthbag design.

To that point, I am going to use earth. Did you you that a home made of 12" or thicker earthen walls will only fluctuate +/- 3 degrees off of the median tempature of the day? So in Taos, where it's 90 during the day and 60 at night, our house will sit at a comfortable 72 to 78 degress without doing anything.

Compressed earth was my next selection, but with this, I still need to either make the block or buy it. To make it I need to have a machine or rent one. I can buy one from $12k, and I don't know where I can rent one. There are folks who will come onsite and use my earth, but they want $1.85 / block to do this. So, if I want to do it I need capital for the machine, time to test the earthen mixture and time to make the blocks. That won't happen, not now anyway. If I buy stabilized blocks they are stabilized with portland which means that it will feel as though I am working with cinder block walls, even though their insulative properties will be of earth. In speaking with folks who have used these, this is tough, dusty and demanding. CEBs, at this point since I don't live in Taos to work on this full time, are out too.

So finally, Adobe. I can buy stabilized adobe blocks (weather proof) which are fairly easy to cut and size (compared to CEB) and have them delivered for $2/block. This saves me the time of making them, figuring out the earth mixture etc. Now I only need to make the mortar. The blocks can be delivered anytime and I can use them when I am ready. This will be my choice.

To make this reasonable, I will be building in 3 phases. 1) a cabin/tool shed combo. This will be a building that is 8x12 and will be about half the size of the next building. This will have water and heat, rubble foundation etc. I will design this in miniture really to make sure I learn as I go. It will have parapets on 3 sides and a sloped metal roof to gather water. We will have an outdoor shower and bath. 2) A guest house twice the size but of the same basic design as the shed. 3) The house. The design is still in question. I will post the layout on the 10 acres in an upcoming post.

CEB No More?

Well I am hear in the solar adobe class, listening to stories and I think I am going to switch to Adobe. Still thinking. Will post more later.

Passive Solar - Its more than pointing the home south.

I was speaking with a friend who is planning to build a "passive solar" home off the grid. The plan is stick frame 2x6 walls, point the home south, cover the south wall with windows and sit back and enjoy. I asked them about the floor and the plan was to lift the home off the ground and use a crawl space. I asked them about their overhangs for the south and they hadn't thought that out yet. Although this home may meet there needs, as similiar home designs meet the needs of many people throughout the world today, to me a few simple changes could make this home REALLY efficient and comfortable. I will touch on a few of those in my next few posts including thermal mass, trombe walls, overhangs for south facing homes and glazing to livable square footage ratios.

Next Adobe Class

I am excited to head down to Bosque, NM to attend the second of two classes put on by the SWSA school. This will be a hands on class, where we will have a earthblock press (AECT manufacturer) available. We will be covering rubble trench foundations, CEB building, slurry's, running electrical, bond-beams etc. This should be an exciting class. I will be taking great notes and sharing them here.

Kim and I have also been trying to figure out our ultimate plan. After attending the last class I was afraid our first guest house was too big, even though it was small. I was sitting in the hotel and I was thinking "you know, if our first house is a guest house, then it doesn't really need to be much bigger than this room" so......I redid my guest house plans and made it 24x24, which is the same size as the detached two car garage I just built here in KC. I removed the laundry, made the bathroom a little smaller and pulled out the kitchen. Now I am worried that if I get the guest house built, then for some reason I can't build the main house, we won't have everything I need in our first and at that point only house. Decisions, decisions.....

Point Loading - Uniformity is Key with CEB

One of the attractive aspects of CEB is the fact that you can use a thin slurry to lay them, rather than a thick mortar joint. As I continue to explore building with CEB, I have determined that uniform block height is essential if mortar joints are not planned to be used. Eliminating mortar joints, like those used with Adobe, Brick or cement block, reduces the amount of skill and labor required thereby enabling the DIYr and saving resources.

As CEBs are layed/stacked, and courses rise, the blocks in the lower courses, experience increased downward pressure. If the blocks are flat against each other, or if they sit in a "bed" of mortar allowing them to lie flat, then the downward pressure in any area of the horizontal block faces is fairly equal. As mentioned equal pressures occur due to either 1) a mortar joint, or 2) uniform block height.

Since one of the benefits of a CEB wall is a thin slurry set thereby reducing labor and skil, uniformity then becomes key. If blocks are not uniform in their height, then as courses rise and downward pressures increase, the chance for "Point Loading" increases. As shown to the left, point loading occurs when one specific point or area of a higher coursed block carrys more of the dowward force due to a non-uniform lower block. The lower block has only one "point" that it is in contact with the upper block.Carrying the forces in this one area, and not spreading the load across the face of the block, can cause the block to crack or fail, thereby eliminating the effectiveness of the wall.

My next post with focus on two methods used in block production, vertical and horizontal pressing of the block. Each has pros and cons when it comes to their effect on Point Loading.

Finished Solar Adobe Class

Well I finished the Southwest Solar Adobe Class, taught by Joe Tibbets. It was a very informative class. I met quite a few people who are looking to build with adobe and / or compressed earth and was able to start to test some of the soil from our site in Taos, via the shake test and golf ball test (for lack of a better term). I also learned how to determine True South, so you can orient the home correctly, learned about a Speed Leads and also determined how to figure out Sun Angles so you can then determine placement of windows and length of overhangs. I have updated the main site with much of this info already, but will be expanding and reiterating it here as well.

Heading To Taos

Well I am heading to Taos this weekend, specifically to Albuquerque to attend the first of two classes taught by the Southwest Solar Adobe School. The class is their Passive Solar Home Design class. It will cover the design of adobe / compressed earth block homes, specifically going over the NM building codes for compressed/rammed/adobe earthen homes.

After the weekend is done, I will be staying in Taos, on our new property, scoping it out, taking picture, meeting with the Taos Planning/Building department to determine next steps etc on obtaining a building permit. I will also be digging up a couple hundred pounds of earth and will be taking that to Powell and Sons, just north of Albuquerque. They manufacture compressed earth block machines. Compressed earth is how I plan to build our homes. I spoke to Bill Powell and he agreed to compress my dirt from onsite so we can see whether the onsite earth is of the correct make up to use in a compressed earth home.

I initially started my plans and design using earthbag construction as the method. After I realized I wouldn't be able to simply take time off work to build the home in one fell swoop, I realized earthbags might not be the right method for me. Earthbags won't allow me to stage the building of my property. I can't fill them, then come back a year later and stack them, really. If exposed for too long, they will deteriorate and I can't gaurentee that I can keep them covered. This requirement, along with my requirement to use earth, pointed me to stabilized compressed earth. Thanks and I'll share more later. You can also find more at my primary website, ourTaosHouse.com