Tag Archives: outdoor kitchen

Building an Earth Oven Part I: Foundation, Dome, and Structure

An earth oven is an oven made of cob (a mixture of clay, sand, and straw) with insulating features (firebricks, bottles).  It is an extremely efficient and sustainable method of doing any baking you might need to do. One firing of your earth oven can allow you to bake different things for hours (pizzas, breads, casseroles, vegetables, etc), and it takes only a small amount of wood to heat.  We fire ours by simply picking up deadfall sticks and branches, cutting them up, and that’s all we need. An Earth Oven is fully sustainable to build and to cook with, and you can locally source literally all of the materials for the oven (and in fact, minus fire bricks, you can probably harvest everything you need from your own land or the land around you).

The completed earth oven

The completed earth oven

An Earth Oven allows you to connect deeply with the earth itself, encouraging you to slow down, root, and ground.  It is certainly a nice example of “slow time” and “slow food”, as the oven takes a few hours to fire before you can bake in it, and it requires some learning.  With that said, the rewards of this approach way outweigh any challenges you might experience as you learn and grow.

 

The other thing about your oven that is rarely discussed is that it is truly a sensory experience.  Your earth oven will allow you to bake any number of delicious creations–and when you bake in it, the smell of the bread permeates the clay itself, and it has this incredible smell, unlike anything you’ve ever experienced.  Even on cold days, being near your oven will keep you warm (and your oven will stay warm for literally hours–possibly all night).  It is just such a wonderful thing.

Fire in the near-complete earth oven!

Fire in the near-complete earth oven!

Earth ovens are a wonderful kind of “hearthspace” where we can cook foods for ourselves and loved ones, use natural materials to build from the land and honor the land, and create a very sustainable and low-input cooking method that is a joy to make and a joy to bake in.  In this new series, I’ll offer full details about how to build an earth oven step by step!  This series will have three posts–today’s post covers materials, preparing the foundation, preparing the base, and creating the dome.  Next week’s post will explore insulating the oven and finishing the oven through a mosaic/cob, finish plaster, and options for doors.  The final post will explore how to cook in your earth oven and some tips and tricks I’ve learned in my first year with the earth oven.

 

Preparation: Materials

In order to build your earth oven, you will need to prepare some materials and do some prep work.  Earth ovens are not expensive to build–most of the investment is in your own time and labor.

Materials for building:

  • Stone and urbanite: You will need some kind of base for your oven; most people use local stone or even urbanite for a strong foundation.  Urbanite refers to waste materials like broken bricks, broken concrete blocks, etc.  You can use urbanite to “fill” the inside of your base and create a stable foundation.  I have also seen people build ovens on old large stumps or platforms.
  • Subsoil / cob: First, you will need access to your subsoil (that’s the soil that is not full of organic matter, but the soil below it). You will need quite a bit of subsoil, so make sure you have easy access. Once you have access to the subsoil, you will want to do some soil testing (which I explain in the link) so that you can be sure you have good subsoil to work with.  To access subsoil here, I found a tree that had gone down and uprooted itself–the roots and ground below it was full of all of the subsoil I needed.
  • Straw:  You will need a bale of straw for your cob.  Straw adds strength, can provide insulation, and can help hold your structure together.
  • Sharp sand. You may also need some sharp sand (known as builder’s sand) depending on what your cob tests reveal. You can get this from a landscape supply or building supply place.
  • Sand: In addition to the sharp sand as an additive, you will need sand to build your sand dome.
  • Newspaper: You will need 3-4 newspapers for your dome.
  • Bottles: You will need at least 20 wine bottles for insulating your base. These can be foraged from recycling bins, saved by friends, or even found at local restaurants. Depending on your structure, you can also use smaller recycled bottles to help with insulation (I did this, but some people use an only straw).

Tools for building:

  • Wheelbarrow or cart: You need something to move materials around your site.
  • Shovel: A shovel for digging subsoil and moving cob around.
  • Screen.  To prepare your subsoil, you will need to screen it of larger items (stones, debris, etc).  For this, you can build a simple soil screener (this also works great for screening compost!).  Make your soil screener large enough that it will sit over your wheelbarrow or cart that you will be using to move it.  I built mine with scrap lumber and 1/2″ hardware cloth.
  • 5-gallon buckets: A few buckets are super helpful.  They can move cob from where you mix it to your oven.  You can fill some with water to rinse your feet.
  • Tarps:  A small tarp will allow you to mix your cob.  You might want several, especially if you are doing the work yourself (I found that when I was doing the work myself, I would gather materials – screen cob, gather rocks, etc, on one day and then build on the next, so tarps were able to keep my cob screened and protect it from the elements).  You also will need a tarp to cover your cob oven until you can have a structure built for it.
Source of clay / subsoil - a tree that uprooted during a storm

Source of clay / subsoil – a tree that uprooted during a storm

Cob screen in action - this was built with scrap lumber and 1/2" hardware cloth

Cob screen in action – this was built with scrap lumber and 1/2″ hardware cloth

Other Tools and Materials:

  • Pizza peel (I created one from an old aluminum pan and an old rake handle)
  • Firing door and baking doors (more on this in an upcoming post)
  • Shelter structure

We’ll cover these last three in an upcoming post.

Preparation: Oven Size

You can decide how large of an earth oven you want to build.  There are many measurements in the Build Your Own Earth Oven which I used as a reference.  Here’s a simple diagram of the oven and dimensions that I used.  These allow you to figure out how large of a foundation and base you need and will determine the overall structure.

For example, to get good airflow, I created an oven that was 27″ in diameter, which included an 18″ high dome.  Your door should be 63% the height of the oven, or 11.5″ high.

Your oven can be larger or smaller, of course, depending on your needs.

Preparation: Selecting a site

I think it is really important to spend time selecting the right space.  Your space needs to drain well (especially if you are in a temperate climate that has snow/ice).  Your space also needs to be protected from the elements as cob is a natural material that will weather quickly if left without protection.  Your space should also align with your landscape (see setting intentions with nature).

Your oven should be somewhere easily accessible.  You will need to tend a fire every 20-30 minutes for four hours in order to have an earth oven hot enough for pizzas or other baked goods.  Thus, you don’t want to put it so far away from your house that its hard to tend the fire (but not close enough to cause any insurance issues!)

For my earth oven, I decided to build in a little nook on the edge of the property that leads into forest.  That provided both shelter from the elements (and it will get a permanent roof this year) as well as being pretty close

Preparation: Clearing and Foundation

To build your earth oven, it begins with a good foundation. Any cob structure should have “a good hat and feet”, and the foundation is the “feet” part of that equation.  Here is step by step how I built my foundation.

I began by measuring out my foundation – 46″ based on the height of my oven.   Then I removed all of the plant material (as described in this post); I worked to replant any material that needed to be replanted, etc.

Clearing the space

After clearing, I dug down 1.5 feet and added a gravel base for drainage.  Its hard to tell from these photos, but we are on a slight incline, so I made a drainage area to the left of what you see here.

Foundation of gravel

Foundation

Preparing and Mixing Cob

The next step is to screen and create your cob.   I went to my site with my wheelbarrow and put a 5 gallon bucket at a time in my screen.  Using a rock, I worked the cob through the screen. (More details about making cob here).

Screening cob

Screening cob

After that, I moved it to my building site and prepared to mix the cob.

Subsoil screened and ready to mix!

Subsoil screened and ready to mix!

To mix the cob, you will need an old tarp, two or more buckets of water (I like to use warm water!), and some happy feet.  First create a well in the center of your cob and, just like making noodles or dough by hand, then start mixing the cob with your feet.  You can use the tarp to flip the cob and keep working it.

For building, you will want to also add handfuls of straw (I cut the straw up so it’s a little shorter) and work that in.  Ideally, you want something with a good consistency that sticks together and isn’t too wet and crumbly.  You can add more water or more soil as you mix.  I have more detailed instructions on mixing cob in an earlier post.

Mixing cob

Mixing cob

You can also get others to help you–friends, children, or even geese.

Goose helpers

Goose helpers

Building your base

In addition to the cob, you will also need something to build your base up that is fireproof and stable–rock or brick is a very good choice for you. For my foundation, I used a mixture of cob along with locally foraged stones and urbanite (old concrete bricks that were broken and strewn about the property.) A good foundation and good base are critical to the success of your oven. You want to build your base high enough that it’s comfortable for you to fire and use the oven.  I kept mine pretty low cause I like to sit on the ground when I work!

I began by mapping out a circle (using a string and some chalk) and building the outside of the circle up using the cob as a mortar.  On the inside, I added my urbanite brick pieces and filled in all holes with smaller stones and cob.  Here’s the first layer.

Building the base.

Building the base.

As I worked, I continued to build up the stones on the outside.  Since I also planned some decoration, I had stones I had already added mosaic to that I wanted to include.  These pieces were made of mosaic materials leftover from both from doing my mosaic bathtub a few years ago + broken pottery and plates that I save.

My mosaic stones

My mosaic stones

It took me two building sessions, but the base continued to grow.

Base after adding mosaic stones

Base after adding mosaic stones

You can see that I’m building up the inside of the base as I build up the outside of the base.

Base before insulation layer

Base before insulation layer

At this stage, I have the base at the top level and as high as I want it.  You can see I am using a piece of wood and a level to check to make sure everything is level as I work. The next step is to add the insulation layer to the base.  The insulation layer is made up of a straw-rich cob combined with wine bottles.  Bottles offer insulation, which keeps heat from getting absorbed by the stone below.  Insulation is really an important feature of these ovens–investing the time to do insulation will allow your oven to be used in colder temperatures, hold heat longer, and heat up sooner (meaning you use less wood to make that happen).

Thick layer of cob in base

Thick layer of cob in base

I started this with a thick layer of straw-rich cob. Straw itself is insulating as it traps small amounts of air in it as it is worked into the cob.

Next, I layered the bottles with more cob in between each to create a solid foundation.

Bottle insulation

Bottle insulation

Here’s the bottles with more cob added

Bottles getting covered

Bottles getting covered in cob

After the bottle layer, I used the board to smooth out the layer and wait for the base to dry about a week before continuing.

The base is done!

The base is done!

Except that we have powerful raccoon activity, and that night, someone tried to dig up my base to see what was in the bottles!

Coon activity

Coon activity

I repaired the cob and then started putting a tarp over it at night to deter the raccoons until my base was a bit more dry.

Laying your firebrick

Firebrick layout

Firebrick layout

To start your hearth, you want to put down a fresh layer of cob so that you can set the bricks in carefully.  Slide the bricks against each other and make everything perfectly level.  To make an oven that is XXX” inside (which is enough to cook a few breads and two small pizzas, perfect for small groups or families) you can use fifteen firebricks in the following pattern (the two firebricks in the back were redundant and I removed them later).

Notice here that I’m also planning a lip to pull my pizzas in and out of the oven.

Circle for dome

Using a string, I made a circle to show me where to build the sand dome for the oven itself.   Now I’m ready to build the actual oven.

Creating Your Sand Dome

I think the most labor-intensive part of this entire process is building the dome and cobbing the dome. Everything else can be done in stages, but this really has to be done all at once. This part is a great time to invite some friends or family to help you if you are doing this on your own.

Start by mixing 1-2 large batches of cob (with straw reinforcement) and tarping that while you build the dome.

To build the dome, you will want a ruler (to test the height of the dome), newspaper, and a few wheelbarrows of sand.  I mixed my sand right in the wheel barrow and got it to a consistency where it would build up well.

Mixing the sand

Mixing the sand

Building the dome

Building the dome

So then, start building the dome, using the guide you drew.  I stuck a metal art ruler down the center of the dome so I would know exactly how tall it was (with a goal of 18″ tall).

As you get further along, you can take a small board and smooth and shape the sand dome.  PUll out the ruler, and you are ready to build!

The completed dome

The completed dome

Go head and coat the whole sand dome with a layer of thick wet newspaper (this creates a barrier both to keep the cob from sticking to the sand and gives you a sense of where to dig out later.

Now, you want at least a 2-3″ thick layer of cob all around the dome.  You dont’ want to press the cob into the dome, but rather, shape the walls downward with your hands.

Building the oven

Building the oven

Keep working your way up.

Oven build continued

Oven build continued

A lot of ovens have some kind of door area. We used old bricks to build our door area (planned out in advanced).  To keep the door balanced, we added two pieces of packing foam that we cut to the right size.  These were later pulled out when the structure was dry.

Building the arch

Building the arch

The arch proved a bit tricky–we layered sticks in between the sand dome and the foam arches and that provided enough stability until the oven dried.

Here is our completed first layer of the cob oven.

first layer of cob finished!

first layer of cob finished!

At this point, you will want to give your oven some time to dry.  We put a little pavilion over it and allowed the summer sun to dry it out.

Digging out the oven

The next step is to dig out your oven and light a few small fires to help dry out the inside of the oven. You can just use your hands, a small trowel, or a stick.  You want to be careful as you dig out so that you are not digging into the cob itself (hence why the newspaper barrier is so useful).

Digging out the oven

Digging out the oven

I used my shovel to remove the bulk of the sand and then got in there with my hands as I got closer to the walls. I let the oven sit another week after I pulled out the sand, and then I lit a small fire for a few days to get the inside dried out.  Here’s the very first fire.

First fire

First fire

Alright! That’s over half of the oven build.  In my next post, I’ll show how I added layers of insulation, a final plaster, and also decorated it with more mosaic pieces that were salvaged from broken pottery.

Goose helpers and the druid builder!

Goose helpers and the druid builder!

One final thing I want to say now is this is an incredibly good way to connect with the element of earth.  There is nothing more grounding than having your feet and hands directly in the soil, shaping it, honoring it, and getting to know it.  I really enjoyed my time building this and felt incredibly grounded afterward!

Sacred Gardening: A Druid’s Spiritual Approach to Weeding and Clearing Plants

A shrine for the spirits of nature in a new outdoor kitchen area

Druids revere all nature as sacred–but what happens when you need to weed your garden? What happens when you need to clear a new area for a project where lots of things are growing? Is there a way to clear plants or trees honorably and with reverence?  In fact, there certainly is!  In today’s post, I’ll walk through some simple suggestions for how to weed and clear plants respectfully and with reverence. This is all part of my philosophy of Sacred Action, or bringing earth-honoring, care-oriented activities into our every day life (if you are interested in this concept, check out my Sacred Actions book!).  This is part of what sacred gardening, creating a true Druid’s garden, is all about!

Our big project this year was starting to build an wood-fired, naturally built outdoor kitchen with a maple sap boiler/grill, an earth oven, a small pavilion and set of rocket stoves (this is an ongoing project and I’ll share more about it in upcoming posts). In order to do this, we had to clear a small bit of land. Where we are situating our outdoor kitchen is on the edge of a clearing with a shaded overstory, just as the forest begins. The tentative plan for our earth oven was about 6′ into an area with some brush and small trees. We were hoping to use this spot  for the earth oven because sometimes we get bad winds from the fields that are to the south-west of our home, and by locating it slightly in the brush, it would allow us to provide it some additional shielding from the elements. But, this particular spot required me to clear a small 5′ path and about an 7 foot round area in the brush–assuming the spirits of the land and plants agreed.  I’ll walk through the general principles using the clearing of my earth oven space as an example.

1. Recognize the agency  and sanctity of nature by seeking permission and offering gratitude.

An offering bag near some garden weeds that will be cleared

One of the first things to remember is that if we are going to cultivate reciprocal relationships with nature, we must treat nature with respect, reverence and recognize nature’s own agency.  This means we do not take from nature without permission (treating her with the same respect you would do any other person. There are different levels of permission: one-time permission and ongoing permission.

Getting permission for anything is twofold: seeking it and allowing the necessary time for negotiation and conversation.  Don’t expect to get permission to clear a large area of land 5 minutes before you want to clear it.  Seeking permission begins with simply spending time engaging with spirits of the land and explaining what you want to do and why. Explain what you would like to do and how you will do it.  See what results from this converation: sometimes you can get a clear go-ahead, while other times, the spirits may want something in response (e.g. clear this area but leave this area to grow wild; build this shrine, use everything that you’ve cleared, etc).

If you are clearing for a permanent space (such as a garden, outdoor kitchen, home, etc) you can seek a blanket permission statement.  This means that you have the general permission to create the garden and then keep it as a garden, clearing as necessary.

Two months before starting construction of the earth oven, I began by asking permission.  I started by making an offering at the space I wished to clear and speaking aloud what I would like to do, where the boundaries of it were to be, and why.  I asked the spirits to think about my request.  A week later, I returned to the spot and we started discussing. I came back several times over the course of a few weeks and after that, I received the confirmation that I was permitted to proceed. As part of this negotiation, I was told that each plant species would have something different they would like me to do as I cleared.

2. Setting Boundaries for Activities

As part of your request, make it clear what you plan on doing and how long this agreement lasts.  For example, if you are cultivating a garden, make it clear that you would like permission to tend this garden throughout the year and weed any plants that come up in the garden that you haven’t planted, etc.  This allows you to set some clear boundaries for the kinds of activities you will engage in over time.  You can also set boundaries about other things, such as not using any chemical sprays, etc.  The idea here is that you will make a clear agreement with the spirits of the land that you are both satisfied with so that you can proceed.

In the case of our earth oven, I agreed to tend the path and boundaries of our earth oven space and also to cut back some of the surrounding areas if they grew too close to the oven, always asking the plants’ permission.  We established where the areas of the other outdoor kitchen were to be before proceeding.  I was also asked to build two smalls shrines, one to invite the spirits of the hearth to join us (see the first image in this post) and a hidden shrine to honor the earth elementals.

You also may need to negotiate with specific dominant plant species in an area.   For example, in the case of our garden, I’ve made it clear that dandelions are welcome to grow anywhere, but I will be harvesting any within our garden areas for making food or medicine for ourselves and our animals.  But, any dandelions that grow outside of the bounds of the garden will be undisturbed (unless I further sought permission to harvest them for a different purpose, which would be a different negotiation).

3. Clear mindfully and listen to the voices of nature as to how to use cleared material.

Once you have permission to clear an area, establish a garden, or weed regularly, the next step is to start clearing it in a way that is reverent and respectful.  I like to call this “mindful” clearing.  I’m going to clear in a gentle manner, pulling out each plant, checking in with each plant to see how they would like me to proceed (cut you off at the root? Harvest the root? Put you in the compost pile? Feed you to the geese?).  Thus, as I clear, I am also engaging in deep connection with the plants and hearing their voices for how to proceed. As I do this, I continue to make offerings, I sing songs, and I raise good energy for the work I am doing.

Beginning to clear the area for the earth oven

I work to do as much clearing without the aid of fossil fuels as possible, relying on hand tools, as this allows me to get closer to the individual plants I am clearing. Once in a great while, I do have to use a battery-powered lopper or chainsaw, and I let the spirits of nature know what I am doing before I do anything.

So in the clearing of my earth oven space, I spent about 2 hours clearing the space, while I was in a meditative place.  Using movement meditation, I cleared my mind as I cleared down to the soil, making sure that each plant I was clearing had a chance to share what they would like to see happen.  I ended up transplanting several wild yams into another section of the forest.  The Allegheny Blackberry asked me to take their roots and use them for magic (they have been teaching me their magic for many years now) and to compost their stems and leaves.  The small spicebush asked to be potted and given away.  The Virginia Creeper had me pull out enough to clear, asking me to make a small wreath of her and then place that wreath on the altar.  And so it went with each of the plants in this space, where I listened to their voices and did my best to honor their requests.  In the end, I had not only a cleared space but new magical plant knowledge and several roots for my spiritual practices.

I do the same thing in my garden as I am regularly weeding and tending. While I don’t necessarily need steps 1 and 2 each time I got into weed the garden, when I am weeding, I am still listening to the voices of the plants and honoring what they would like me to do with them.  I am treating them in reverence and respect, even as I clear them.

Eventually, you may find that even the most dominant weed can be negotiated with to grow elsewhere.

Doing these practices in this way allows you to both hear what the plant spirits may offer you as well as give you a chance to learn some of the uses of common plants in your area.  For example, if you are clearing a garden, many garden “weeds” have tremendous herbal and edible uses including lambs quarters, ground ivy, pursuance, dandelion, red clover, chickweed, and wood sorrel, to name a few.  If you are pulling out something and you don’t know what it is, take a few minutes to learn and do what you can to make use of that plant for food, medicine, crafts, or spiritual purposes.

4. End in Gratitude

Wood Sorrel

Wood Sorrel, garden weed, delicious food!

Finalize your work each day in gratitude–gratitude for the land itself, the soil, and any plants or materials that were moved or pulled as part of the work you were doing.  Recognize the sacrifice that these plants have made and honor them.  You can practice gratitude by making offerings (such as this offering blend), drumming, dancing, doing a land blessing ceremony, or any other number of things.

In the case of my earth oven, the end of the clearing, I again sat with the space and honored it with flute music and offerings.  I meditated to see if there were any additional messages, and if not, I continued to work on the project.  The next steps in the project were to create a draining gravel foundation to prevent frost heaving, and so when I went back to the site a few days later to start removing soil and subsoil, I made sure to continue to make offerings at the shrine I built and continue to offer gratitude.

Conclusion

As the above explores, the key to honoring nature while also tending spaces, weeding, or clearing land has to do with the approach.  Rather than immediately moving into clearing, spend time honoring the spirits of the land first, the physical bodies of the plants to clear, and take your time to make sure you are engaged in reverence and respect.  This kind of practice integrates spiritual practice with everyday life in the practice of sacred action, and can certainly deepen our own relationship to our immediate landscapes.