Friday, December 31, 2010

Laying The Oven Floor

Once you have the bricks home it's time to lay your oven floor. I used a 2x4 about 8 feet long as a screed to make sure the sand was smooth and even. Then I used a level to make sure the top of the base level in all directions. That was really easy, once the sand was screeded I just had to add a little or move a little to make it all level and then screed it again and check with the the level until it's all level and smooth.

Now I had already looked at my pans and pizza peal and decided that the door needed to be more than 20 inches wide. Which works for me since the oven door should be about half the size of the internal oven space. So a 24 inch door works for me. That is 8 bricks laying next to each other. Remember that if you are building an arch like I did then leave space for a base brick on each side of the door base bricks.

This first step really works well with string. Lay string across the round base to determine where the center of the base is and where the door will be. In the picture below I drew out this layout.
Now when you start laying your bricks lay the door first. In my case I laid 8 bricks so I put four on each side of the center line. I also used the center line as my starting point for the running bond. Below is another picture I drew out to give you an idea what I mean by running bond and the fact that the oven floor doesn't extend to the outside of the base except for the door.

OK why did I use a running bond and what is it? Well there are many different bonds for brick. The bond just means the pattern used when laying the bricks. I used the running bond because I didn't have to cut any bricks. With my bad shoulder and back injuries not hammering or sawing is a good thing. The running bond is simple enough for anyone to lay. The bricks are laid end to end and the next row is offset by half a brick. That means that you line up the middle of the next brick with the ends of the bricks in the row before it. You can see in the picture above what the running bond would look like.
One last note about laying the bricks. Place the bricks straight down tight against the previously laid bricks. This keeps the sand from shifting or getting dug out or moved. If that does happen then just remove the brick you place and smooth out the sand and replace the brick. After you get you bricks laid then use a level to make sure your bricks are nice and even and level. If a brick is too high just use a rubber mallet and tap it down. It's that easy. Once those bricks are laid you're ready to move on to building the oven.

Getting The Bricks

Once the base was done it was time to start building the first oven. At this point I had to decide what to make the oven floor out of. I looked at all of the options and found out there was more than I thought. The oldest ovens had cob, stone and clay brick floors. Some of the more modern ovens had primarily fire brick, formed clay or metal floors. So I had to decide what you use for the floor. I knew the solid fired clay was out since I didn't have a kiln and was way to expensive. The metal floor was out because I didn't have that much and I wasn't sure how long it would last or how well it would hold the heat. So that left me with fire brick, brick and cob. I seriously thought about using cob but, all of the information that I could find said that it took a lot of maintenance and repair.

So I decided on brick but, I wasn't sure what kind to use. Again I started researching and I was really surprised at what I found. The vast majority of people, companies, researchers and experts recommend using fire brick. What they don't tell you is how much energy goes into making the fire bricks. The fire bricks require specific mineral mixes to make and those minerals all require mining. Then they have to be pressed by machine into shape and finally fired at extremely high temperatures. This process uses an incredible amount of energy and releases a large quantity of CO2 per brick. The clay brick by comparison is a mix of clay and sand put in a form to set, then removed to air dry and finally fired. The firing temperature for the clay brick is much lower than the fire brick.

Well I liked the option of the lower CO2 emissions from the red brick but, everyone I found says use the fire brick because the red brick isn't as good and won't last. Then I looked up clay brick ovens and I was amazed. I found restaurant ovens that have been in constant use in some cases for over 100 years here in the US. I found all kinds of information on brick ovens in Europe that have been in constant use for over 300 years. I also found a ton of sites detailing ovens between 50 to 80 years old.

So after looking at all this I couldn't fathom why so many people were trying to sell everyone on fire brick. Even many of the green building sites recommend them. I figured if the clay brick lasts even 50 years then it would be well worth it. So at this point I had decided about 80% that I would use the clay brick.

My next step was to find the bricks. Since cost is a factor in this project I wanted to try and find some reclaimed bricks to use, preferably free or really cheap. My efforts were a bust. Several times I thought I had found free bricks but, they were always gone before I could get them. After a series of disappointments I gave up and went to the local Home Depot. OK I know I wanted to do this without spending much if any money but, it had been several weeks since the base was completed and I really wanted to move this project along. So I looked around and found the bricks. I found the three types of bricks I could use were the new clay brick, the used clay brick and the fire brick. Well the fire brick was $2.15 a brick so forget it it was too expensive. What I couldn't understand was why the used clay brick was $0.52 per brick and the new clay brick was $0.43 per brick. So I opted for the new clay bricks.

OK I need to take a step back and let you know how I figured out the number of bricks that was needed. I know your eyes just rolled back into your head while saying not math! Alas yes math is required but, it really isn't hard at all. In my case the internal oven was planned on being 48 inches in diameter. That would be a 24 inches radius. Yes I know another fancy term but, the radius is just the measurement from the center of the circle to the outside or half of the diameter. We figure out the number of bricks needed by figuring out the area of the brick and the area of the circle.


Wow now take a deep breath because the worst is over. I do have to explain a couple of things though. If you noticed in the math above the diameter that I'm working with is only 60 inches and it looks like I left some things out but, I only want the oven base under the thermal layer and not all the way to the outside of the base. The idea is to keep the heat inside the oven and not any further. So I figured that I would need 89 bricks plus I knew I wanted to make my front arch out of brick as well so I estimated 120 bricks would be needed.

Breaking Ground

Well hopefully at this point you will have taken the time to make all of your choices and decisions as to the size and locations of things. As well as the materials that you wish to use and their locations. Once these things are done and you have your plan in hand along with your trusty tape measure you're ready to break ground.

OK when I say breaking ground what I'm talking about is grabbing a shovel and digging. I know that sounds like work. No really, when you choose your size and location you will have to have some sort of foundation. If you are building in a wet or rainy area then you will need good drainage. A rubble trench would work well in that situation. That means you have to dig a trench about 12 inches deep and slightly wider than your support walls. You then fill in the trench with gravel and begin laying your first coarse of your support walls on the gravel. If you're building in a dryer climate than you only need to dig a shallow trench and lay your first coarse in that. The truth is that even if you were to build your base on flat ground with no trench and make it solid then it would be so heavy it would be very unlikely to ever move but, the foundation makes for a much longer and more stable life.

OK so now on with the show. I started with a shallow trench, about 6 inches deep and laid the first coarse of urbanite. I then mixed up a thick clay mud and sand mix to use as mortar. I then began laying the progressive courses and mortaring them into place with the mud mortar. Now I had to keep in mind that the finished height of the support walls needs to be about 7 inches less than the final height of the floor of the oven. We built the support walls in one work day. We waited for a day to allow the mortar to set and begin to dry. Then we began to fill the internal voids with the dug up soil. We would fill about 10 inches then tamp it down and repeat the process until the voids were filled. After the voids were filled I used the hose and applied some water to harden the tamped earth. This worked extremely well. Then we let it dry and cure for several days.

A word of advice for those with helpers like myself. Be careful when everything is lined up to start with. I say this because some how when all was said and done our base was suddenly very out of round. I still don't know how it happened but, I knew I had to find a way to fix it. Enter the cob. We began learning how to mix and what the right consistency was for the cob. This comes down to simple things. The cob should not be too wet. This is important, cob can't be overworked but, it can be under worked. Under worked cob is coarse and doesn't stick or blend well when placed. To place the cob start with the cob rolled into balls so it's easy to handle and push, rub and smack it into place to get the shape you need on your base.

So we struck out filling in and smoothing out the odd shapes to create a fairly round oven base and counter. Since we didn't want one section showing stone and another showing cob so we covered the entire base with cob. Note of importance here is to know that you can only add one or two layers of cob at a time. If you try to add too much too fast it will fall off. You have to add a layer and let it set before you add a second layer. So it took us about two weeks to cob the outside of the base. This was definitely a learning curve for us so be prepared but, don't get discouraged. Once any cobbing is completed give the base a few days to cure and dry. Also remember to use the clay slip when the layers have dried to wet the under layer and act as a bonding agent between the layers.

Once the base is dried mix up a batch of cob and make sure the balls are more than 3 inches in diameter. Then place the balls all around the perimeter of the round portion of the base. Then use a level when working the cob balls down to 3 inches. Let this dry for at least another day. Now fill the top void with a medium grain sand and use a screed and level to smooth and level the sand. This will prepare your base for the oven floor. These are the same steps that I followed.

I do regret not having any pictures to show of this process as we built the base. I had some wonderful pictures of the process to the finished base of all of my kids working on it. Unfortunately I had not downloaded the pictures before my phone was stolen. I will begin including pictures as soon as I get to the point where I got a replacement phone and began taking pictures of the kids and the oven again.

Thursday, December 30, 2010

And So It Begins

Well by now hopefully you've read the previous posts so you'll have the advantage of knowing the things that I had to figure out. Don't get me wrong there are lots of websites and videos out there but, they all seemed to miss bits of information and for what ever reason no one seems to build more than an oven or a counter to put in a barbecue insert. A big part of my reasons for writing this blog was to fill in some of the gaps in the available information as well as to add to the available information with my ideas and experiences that will hopefully along the way help someone else.

So hopefully by now you are planning your outdoor kitchen. The easiest way to do this is to start with a simple sketch or line drawing. If you have drawing software you can use that. The idea here is to get your ideas on paper. This will help you organize your thoughts into a cohesive plan that will work for you, your style of cooking and your particular location. Below is my current plan that I am working from. I say current because I've changed and adjusted the plan about a dozen times. This current plan revision has been measured out and adjusted to fit the space accordingly.



I marked the ovens on the plan with 1 and 2. The 1 notates the large oven. This is the first oven that we built and the starting point for this blog. The 2 is a planned second oven but, this one is to be smaller so when we are not cooking the big meals an oven is still available without having to fire off the large oven each time. The Barbecue grill is going to be mounted as an insert into the counter. I already own a large charcoal/wood barbecue that I plan to modify and put in as the insert. The wood stove burners I plan on building are of a very fuel efficient design. The open barbecue grill will be for those large pieces of meat or roasted vegetables. The fireplace will do several things in this design. First it will provide a place to build a fire to warm the dinning area. Secondly the fireplace will act as a privacy wall making this area more of a room than an open area. Lastly the fireplace will act as a wind block for the cooking area. The kitchen counters are for preparing and serving food. The center counter will be designed with a high and low side to the counter to accommodate bar dining. I plan on running conduit and plumbing as I'm building so that I can have electricity and water in the cooking area.

Now let me throw in another twist to my design. I am planning on adding copper piping on both ovens, the barbecue grill and around the stove burners. OK why would I want to do this? Well I figure that if I have to burn wood why not pass the water through pipes to heat it for hot water in the sinks. Why use a tank and electricity when the fire is already burning?

So as you can see there are many things to consider before you ever start building anything. Take the time and plan your kitchen area well so you'll be happy how things turn out and you'll use it happily for years.

Where Do The Materials Come From?

This is one of the best things about using cob and adobe. You can find the materials just about anywhere for little to no cost at all. If you live in the desert clay soils and sand are everywhere. Wetter climates usually have heavy layers of clay subsoil and clay deposits along rivers, streams and lakes. Sand and clay are found virtually all over the planet. You might have to go dig it up and haul it a short distance but usually you can find it for free. Now understand that if you have the money to spend you can go order clay, sand, brick, block, and even premade adobe bricks. The choice is yours.

Now since part of this project is to spend as little money as possible we've been gathering all of the free materials that we can. We need rock so we go and find it on open public lands. I am not advocating theft at all. I called the BLM and State Land agencies and asked if it was ok to gather the materials. I was told that as long as it was not on private land or on a mining claim it was legal to gather dirt, sand and rock. Mining claims or private property require permission from the owner. I've only found that I needed on thing on private property so I knocked on the door and asked and they said take any of the rock or sand I wanted. It was that easy. I also just talk to people and sometimes I get lucky with people wanting to get rid of steel, brick, block, dirt or just about anything you might need so be open.

I will say this, there is a sense or feeling of accomplishment when you can look over and say not bad for a bunch of junk and dirt. You'll know that what you have done has changed the way you look at things and the way everyone else that experiences using it looks at things as well.

So What's This Stuff Called Adobe?

Now take a deep breath and relax. This one is really simple. Adobe is pretty much the exact same mix of clay, sand, water and straw. It's mixed the best with your feet the same way as cob. If you add more straw then the mix has more insulation but is a little weaker.

That was the easy part. Now the differences between cob and adobe is how they are prepared and used. Cob is rolled into balls or logs and cobbed or cobbled together and shaped to form a solid mass. Adobe on the other hand is formed into bricks, then sun dried and used like a brick.

So this process is fairly easy to do. You start with a form made of wood. Usually a 2x4 or 2x6 is used and you can make a form for one brick or many. How many bricks to put in a form is really up to you. If you will need a lot of bricks or are making large batches of cob/adobe mix then a larger number of bricks in the form goes faster. If you are one person doing this alone then make a smaller or single brick form so it's easier to handle.

So you take whatever size form you decided to make and place it on clean flat ground. Keep a small bucket of water near the form because you want to wipe on some water onto the form before putting any mud mix in it. This will help the mud to release from the form. Now fill the form with the mud mix starting with the corners and finish by using a screed, or board, across the top and flatten the mix in the form. Wait a minute or two and then lift the form. Remember that you don't want the mix to wet or when you lift the form the bricks will sag and run.

Now here is the hard part about adobe. You have to wait. You wait a between one and three days and then turn the brick up on the thin edge. Then you wait for between one to three weeks of drying time before you can start to build with them. At this point patience is a must.

One more note about the forms. The 2x4 makes about a 3 1/2 inches thick brick where as a 2x6 makes a brick about 5 1/2 inches thick. Why is this important? Well a thinner brick dries faster but a thicker brick takes fewer courses of bricks. Also take into consideration that the adobe brick should be larger in size than the red clay bricks. In this project the walls of the cupboards will be about 8 inches wide, 12 inches long and 3 1/2 inches tall. If you plan on using the adobe bricks for a building then the blocks should be larger. The standard size for building walls is 10 inches wide, 14 inches long and 3 1/2 to 4 inches thick.

So What Is This Stuff Called Cob?

To put it simply cob is a building material made from water, clay, sand and straw. If only it were that simple. There is actually a bit of science and definitely an art to making cob. The good news however is that we seem to be programed with the natural ability to understand the art of cob making.

OK so what is the science of playing in the mud? Well cob is specially made mud much like adobe. You need to use the clay subsoil. This needs to be free of rocks, silt and topsoil. It's important to not use topsoil because you do not want the roots or seeds mixed into the cob. The last thing that you want is for you oven to sprout a plant and crumble. So why is the clay important? The clay is the binder that will hold everything together. When fired it will become terra cotta and become a permanent layer on the inside of your oven. The outer layers will not get hot enough to be changed into terra cotta. This is important because the outer layers will be susceptible to water damage. Now you have to mix the clay with the right amount of sand and water. This ratio is in about 2:1 sand to clay mix. So let's say you're using a 5 gallon bucket as your measuring tool. You would use 2 buckets of sand and 1 bucket of clay. You want to use just enough water to allow the mix to be stiff. If you form the cob it should want to hold it's shape but, if it's too dry it will not pack and shape well and will be extremely coarse. This is the art part of things. You will quickly learn to feel the differences in the mix and you adjust the mix by adding more water, sand or clay to get your desired consistency.

Now you'll notice that I left out the part about the straw. Here's why, when you are building the base and the thermal layer if you use straw it will burn out if exposed to the extreme heat of the fire. I learned this and that it makes the cob weaker and it can collapse easily. I opted to not use any straw in the base or thermal layer of the oven. Now the insulation layer will have a lot of straw added to the cob to make it insulate well and reflect the heat back to the thermal layer of the oven. The straw in smaller amounts is used in cob to add tensile strength to the cob. This just means that it helps hold it together and that the fibers make the cob more resilient to cracking or splitting.

OK so why add so much sand if you're using straw? Well the sand adds compressive strength to the cob. OK I know more fancy terms but, it is important to understand. Clay will absorb a lot of water but, that means the clay will have to expand to hold all that water. This means that when it dries it will shrink and that means cracking. Here's where the sand comes in. The sand gets coated by the clay and gets bonded to the other pieces of sand but, the sand won't shrink. So the cracks and weaknesses of the pure clay is greatly reduced and the rough sides of the sand gives the clay a good bonding surface. When this mix dries it's almost as hard as cement and that is due to the sand. When dry it can hold a lot of weight.

Now a word about mixing cob. If you ask my children they will tell you all kinds of ideas about cement mixers and other mixing machines that they want to use. The reality is most experienced people all agree that your feet are the best mixers in the world for cob and adobe. I tried using an electric mixer and it didn't work well and we still had to work it with our feet to get it properly mixed. Oh and I also burnt out a motor trying to mix the cob. Your feet really are the best things in the world to use. Cob is also one of those things that gets better the more you work it. If it starts to dry out you just add a little water and work it in. Now I've seen videos on YouTube and other sites where people are stomping and mixing cob with boots on. OK look we've all played in the mud and this is a great excuse to do it as an adult so just embrace it and enjoy. Also clay is widely used around the world to draw toxins from the body. So just think about the fact that you're getting $100.00 or more clay treatment for free by mixing you cob with your bare feet.

Now a word of advice, do not add the straw to the cob mix until the sand, clay and water are well mixed and ready to be used. Why am I saying this? Well if you add the straw in early is will absorb a lot more water than you realize and you cob will take two or three times longer than normal to dry. If you add the straw at the end of the mixing you may have to add a small amount of water, or better yet light clay slip, your drying time will not be affected much.

What was that I said, clay slip? What's that? A clay slip is your best friend when working with cob. It's made by slacking clay then mixing that with water to the consistency that you need. OK I know, what the heck is slacking? More fancy terms but, it has a really simple meaning. Slacking is taking the clay subsoil and soaking it in water usually overnight. It turns the clay into a thick sludge in the bottom of the bucket that when thinned out with water can be rubbed, splashed or even painted on to your oven to be used as glue to bind repairs and additional layers on. This is the slip and it's your best friend if you can't get everything done in one day. A thick slip mixed with some sand is also a perfect filler for the cracks that will happen. The slip can be rubbed or painted on as a binder between the thermal layer and the insulation layer.

One more quick note about the use of straw. The more straw used the greater the insulation value but it reduces the compressive strength of the cob. For anything that you want to insulate then add some more straw but make sure to cover it with another layer of cob with less straw to protect the insulation. The same holds true for using straw in adobe but, we'll get into that next.

Moving The Base Forward

OK now I know what you're thinking, didn't we cover the base in the last post. The simple answer is yes but, there are some details that we should cover before you begin building your base and there a few things to note to prepare your base before building your oven, as I had to learn some of these the hard way.

If you notice there is a common theme here in these early posts and that is I learned things the hard way. Now I say learned because these beginning posts are playing catch up for you the reader as I only decided to do this blog approximately six months after we began this project. It was also during time that this project evolved into the full scale outdoor kitchen and dining area. This happened through a combination of my children's interest and my own belief in fuel efficient design, using the earthen materials at hand and attempting to be as carbon neutral as possible. OK so what does all this fancy talk really mean? Well it means opening up an outdoor room so essentially adding space to our house and since we live in Arizona it can be used most of the year. As a bonus we don't add heat to the house during the heat of the summer and the food is just better when cooked on open wood fires and in the earthen oven.

So that's a plus but, what does the carbon neutral comment mean? This is really a simple concept. Anything that is burnt creates carbon monoxide and carbon dioxide. When we burn petroleum based fuels, both liquid and gas forms, we release all of the stored carbon in those fuels. Petroleum is created from all of the organic matter compressed and dissolved by the heat and pressure underground. This process concentrates the carbon in all of the organic matter into an extremely dense substance known as petroleum and when it is burnt it releases all of that stored and compressed carbon. Many times more carbon than burning a tree branch. Carbon neutral however means that it only releases the same amount of carbon as it has taken in. So if you burn a tree branch then you will only release the same amount of carbon that was taken in and stored in that branch, therefore you only release what was taken in making the process a repeatable and sustainable cycle. Never releasing more than what was stored.

OK now you're saying what does all of this have to do with the base? Well depending on the size of your oven you may have to fire it from between one to two and a half hours. Now if your base has no insulation under it then you will have to put that much more energy from the fire into your oven. This means longer firing times and more wood. Now it is true that the wood burning is carbon neutral but, charcoal however is not and the extended firing time is not required if insulation is added to your base.

In all of my research and testing I have found dozens of ways to insulate the base from absorbing all of the heat of the fire. The easiest way I found was also the simplest which was to use a medium grain sand that we dug from a local wash. It holds enough air space to hold some heat but not transfer much heat to the rest of the base below. The other popular method I have found was to place empty wine bottles, either laying down or placed neck down in the center of the internal void to add empty air space under the sand. This works well if you are using fine sand and need the air space but, if like me you found a good mix of large and medium sand that holds plenty of air space. The airspace is the key to the insulation but, if the sand is too large in size you won't be able level the bricks of the oven base. So try to keep this in mind when choosing your sand.

Also I found that it's a good idea to seal the outside of your base with cob and earthen plaster as this protects the base from absorbing water but, if you are using cement mortar or stucco or any other sealer than it would be unneeded.

I wish I could have included some pictures of my kids building the base. In my experience learn to take pictures so you can share them later. I did take pictures of them working in the mud, dirt and rock starting from the ground to the point of them standing on the completed base. However my phone was stolen before I was able to transfer the photos onto a computer so they became lost forever. So now as we continue on this project I am much more conscious about taking pictures and I will include them in this blog.

In the Begining There Was A Base

So in the beginning I had to start somewhere. Since the brick oven was what started all of this I figured the clay oven was where to start. With that I had to come up with several questions and answers. These are the questions that I had to figure out:
  1. How large of an oven do you want? Otherwise put, how much food do you want to be able to cook at one time?
  2. How high do you want your oven, or how far do you want to bend down?
  3. What direction does the prevailing wind blow?
  4. What to build the base out of?
  5. How far away from a house or structure is the oven going to be?
  6. How do you want to cook in the oven? Should it have a chimney? Should it have an external door?
I know that seems like a lot of questions and some of them seem basic while others may not make sense but I promise that each question is important and I learned the hard way. So let's start thinking about these questions and see why they are all important.

How large of an oven do you want? Otherwise put, how much food do you want to be able to cook at one time? This seems simple but, every other decision you'll make from here on out is based on this choice. What this comes down to is how much food do you want to cook at one time. As I said in my first post my wife and I have eight children so you can imagine how much food we have to cook sometimes. I opted for a large oven. Most clay ovens that I have read about were a maximum size of about 28 inches in diameter. I did some measuring and calculations and decided that this was too small for the times when we were cooking a lot. In a smaller oven the problem was putting the food in and pulling it out then putting more in and since it's a slow cook what's already cooked would be cold by the time the next items would be cooked. So I opted for the largest clay oven I was willing to build the first time out. I decided on a 48 inch internal diameter oven. This is important because you have to start with the internal oven size and add on thickness of the thermal layer, the insulation layer and finish layer. Add all that together and that's how big your base needs to be. For example my oven is 48 inches in diameter then my thermal layer is about 7 inches thick, so that would be 48 inches and 14 inches, 48 + 14 = 62 inches in diameter. The number to add is always double the thickness of the layer since the diameter is double the radius. So you measure from the center out and then double the layer thicknesses to offset the correct diameter measurements. Now add a 6 inches thick insulation layer and a 1 inch thick finish layer, 12 + 2 = 14 inches. So 62 inches and add 14 inches, 62 + 14 = 76 inches in diameter. This is the required size of the base in order to support the 48 inches internal diameter of the oven. You'll need to make these calculations before beginning the construction of your base.

How high do you want your oven, or how far do you want to bend down? This is simple but important. If you build your oven on the ground then you have to bend way down every time you get into the oven. With my back injury I was not planning on bending down like that. So I decided that I wanted the floor of the oven no lower than about my waist. You'll have to make this choice but keep in mind that if your oven is maintained it can last for years so consider your physical condition now and the possibilities in the future. I had to learn this the hard way.

What direction does the prevailing wind blow? I know this seems like an odd question but, if the wind can blow directly into the oven door than ash and embers can be blown out as well as all over any food that maybe cooking in the oven. A cold wind blowing into the open hot oven can also disrupt the thermal dynamics of the oven. I also had to learn this one the hard way. Now in my case the door is facing the sitting area and entrance to the house but, this aligns the door with the west to east winds that we get here. However in my case this was the best overall positioning so as I'm building my kitchen I have to take this into consideration and make sure to build wind blocks to solve this issue.

What to build the base out of? This is really up to you and it seems to be a very personal choice. My kids and I went out to the desert to collect rocks to use to build the base. While looking for rocks we came upon discarded urbanite. Wait, what was that word? Ya I know it's just a fancy way of saying broken up cement, but it really means any man made stone like material of which cement is only one. So we collected rocks and the urbanite to use as the stacked stone of my base. You can use just about anything you like such as bricks, block, stone, cob, adobe, metal and even wood. The choice is yours.

How far away from a house or structure is the oven going to be? This seems strange to ask but it serves a purpose. As I learned the hard way that I can no longer carry large trays of food and move the door. I need a place to set things down. my oven is about 40 feet from my door so I had to add a counter into my design for the base. You'll have to decide what kind of work space you'll need. Keep in mind that if you think you'll have just enough room you will run out. So make sure to plan ahead because as soon as you start using your oven you will want to use it more and more. There is nothing like food from a wood oven and you'll learn to appreciate that very quickly.

How do you want to cook in the oven? Should it have a chimney? Should it have an external door? Why am I asking this question in regards to the base of the oven? Well again this is something that I learned the hard way. If your base is lightweight and not able to support the weight of a chimney or additional insulation layer then your base will fail. My advice is if you can build it with a 2x4 then use a 2 foot in diameter log to make sure it will never fail. In other words overbuild, overbuild, overbuild. Everything will depend on your base. Ovens that are built on a solid base and maintained have been known to last well over a decade.

So with those questions answered you'll be well armed to begin construction of the base of your oven. Below is a diagram of the design that I used for my oven base. We used the rock and urbanite as stacked stone that we mortared together with a thick clay mud mortar. We then filled the internal void with rocks in the bottom and a damp dirt and sand mix. Be sure to tamp the fill as you put it in. Once the internal void was filled and tamped down solid my base became rock solid. My base is so tough that before we built the oven on it I had to use it as a workbench to repair my car. This required me and a friend to beat pressed parts out and reshape parts with a sledge hammer. My base didn't even flinch. At this point I can honestly say that I think it would stop a car dead in it's tracks.


Once you have your walls built and the internal void filled you'll need to decide whether to cover your base with cob or not. I chose the cob as it will allow me more options for decor and design and allow me to make a waterproof coating when completed.

Next I used a ring of cob on the outer edge of the ring of the base. About 3 inches thick will allow you to fill the top with sand in order to be ready to build the base of the oven and eventually the oven. I would recommend not adding anything else to the top of the counter area until after the insulation layer is added.

Wednesday, December 29, 2010

Introduction and Inspiration

Hello and welcome to my adventure. Since this is my first attempt at writing a blog I thought I would begin with a short introduction about myself and the inspiration behind this project.

So to begin the introduction my name is Robert Dameron and I live in the Sonoran desert in Arizona. I've worked in the computer industry for over twenty years as well both residential and commercial construction. Usually I worked two to three jobs at a time. I guess you could call me a classic overachiever. After moving to Arizona I gave up construction then during the economic down turn in 2005 I left the computer industry and became a firefighter and EMT. I spent several years as a firefighter but, was injured during a house fire, permanently disabling me, which ended my career as a firefighter and EMT. I then spent the next two and a half years learning how to walk and move while coping with the constant pain. To that end I will admit that I am much slower than I used to be and am very limited in how much I can do in a day. This includes typing so my posts won't usually be too long.

Now the good news is that I do have some help with this project. I am blessed with eight children. Yes I know the question and yes I said eight. I have four and my wife has four. No unfortunately they are not all with us all the time. Two of our children are eighteen or over, one is almost eighteen and the youngest is now thirteen. I don't get to spend much time with my children from my previous marriages, but they do come and visit over the summer and some holidays. We have three of our boys with us all of the time. So no matter what we have some of our children here. Our children have almost all had a helping hand in this project and this project would not be at the point it is without them.

So on to the inspiration of this project. My wife and I chose to live outside of the city on purpose. We wanted some land to be able grow a garden, some fruit trees and maybe some chickens. We wanted to be able to see the stars at night and to have space to entertain our family and friends. For me that means a great passion of mine, cooking. Especially cooking with a wood or charcoal fire. I love fresh food cooked over open flames. I also love to bake and roast in brick ovens. So we planned to build a brick oven. When I was injured I suddenly lost both the money required to buy the materials and the physical ability to build the oven. So in an attempt to fight the depression I faced I began searching for an alternative and I found one, earth. Clay to be more exact.

Before I was injured we had begun digging a hole in the ground to use as a cistern to collect and store rain water for irrigation. I can tell you without a doubt after digging in this soil that it has a lot of clay in it. The more I read the more I wanted to read and learn about clay ovens. So an idea that was born of brick had suddenly transformed to clay. So I read and studied everything I could find about these types of ovens. The idea became simple, to build a clay oven from the clay earth we had dug. I also had learned ideas new to me for fuel efficient stoves and open pit cooking. So now my idea began to morph from a single oven to an entire kitchen. An outdoor kitchen, one that would be fuel efficient and by burning wood from dead trees or trimmings making it carbon neutral. Also a kitchen that won't heat up the house on hot summers day but, also an outdoor dining area to be able to enjoy the mild spring and fall days and evenings and a fireplace to take off the chill of those winter nights when then is no substitute for good barbecue.

So now my project has evolved into an entire outdoor kitchen and dining area to be made primarily out of the clay earth that has been and will be dug from here on the same site. This clay will be turned into cob, adobe brick, mud mortar and earthen plaster. My intent for this blog is to chronicle this project so that I may give back to those who have provided me with information as well to help others realize that we can live well and be happy and healthy without having to spend thousands of dollars to do it.

So in conclusion of my first post the purpose of this project is to build a functional and aesthetically pleasing outdoor kitchen and dining area primarily made out of adobe and cob. The intent is also to use locally found and or recycled materials in order to complete the project with very little cost. The purpose of this blog is to share our experiences and knowledge gained with those who share our passions for good food, family, friends, living well, reducing our expenses, being ecologically responsible and anyone else who’s interested.