Jeffrey the Natural BuilderAdventures in natural building

This 22″ cob oven was built over a few weeks.
Everything except the firebrick and stove pipe were collected from within 5 minutes of the house. (And both of those were reclaimed)

The foundation is constructed from dry stacked rocks, sitting on top of that is a cob/rock layer to bring the oven upto a comfortable working height for Pete.
After a layer of insulation, there is the fire brick oven floor.

The fun part was creating the heavy mud dome to contain the fire and baking.
First we created a sand form and then invited some friends from McBride to come and stomp some cob with us!
We had a great time dancing on the sand/clay mix to the sounds of children’s songs. When it was all mixed and ready we built the mud up around our form. Once to the top a hole was cut for the door, and we celebrated with a beer!

The dome was left to dry for a day then I carefully pulled out the sand. The dome held so we built a small fire to dry the mud – then a big fire to cook some pizzas!

Once the dome was completely dry, a layer of chip/slip insulation was added, then finally a coat of earthen plaster to finish the job!

I made the roof structure from maple & willow, using mortise and tenon’s and lap joints. A neighbor came to see the project and offered some metal roofing to finish the job (Thanks Brian!)

I love the transformation that happened when the final coat of plaster went on, tying the whole oven together… but most of all I loved the cooking of pizzas and bread! (The pizzas cooked in 5 minutes and 4 loaves cooked in 10!)

The design and finer points from this oven build were learned from Kiko Denzer’s excellent book Build Your Own Earth Oven”

Starting the fire

The plaster layer begins to dry

The oven with it’s plaster applied

I added a sun motif

The roundwood framing details

I left on some of the branches to make the corner post more decorative

The bread!

Pete enjoys his first pizzas from his new oven!

The dry stack foundation with cob/rock to bring it up to height.

Bottles are inserted into the insulating layer – i’m not entirely sure as to why the bottles are in there… it seems to me that they are not good insulators – the use is probably to provide some support for the dense mud layer that goes on top of this. As this was my first oven I was happy to follow the examples in Kiko Denzer’s book ‘Build your own earth oven’ – Having been through the process now, for my next oven I will use pumice (lava rock) to create an insulating, yet firm layer.

the hearth floor made from firebrick is laid

The sand form is built and smoothed down

we covered the sandform in wet newspaper to protect it and keep it dry, then we did the cob dance!

Big thanks to those who came to help!

the heavy mud mix is applied, a simple door frame is constructed from brick – thanks to Richard for the welding the angle iron