Earth Ovens 1

Ok, I am not totally obsessed with Earth Ovens but I do spend a lot of time thinking, planning and building them. I am not an expert by any means but I thought I could share my thoughts on them.

What do I mean by Earth Oven? 
Literally, an Oven made of Earth. I build a particular design (a sort of pizza oven) but the techniques can be adapted to what you have available and what you want to create; a Tandoor for example. When I say earth, I mean a mix of Clay and Sand.  Someone once said to me "There is a layer of clay a mile thick encasing the planet". Now, I don't know whether this is accurate or not, I think though that the point is correct. Clay is abundant and fairly easily found. Dig a hole, and depending where you are, you will eventually find clay. Soil  is no good; It is full of seeds and micro-organisms, and it ain't sticky enough.  Clay when dry becomes solid but it will develop cracks, hence the addition of sand.

The sand (probably) can't come straight off the beach. Beach sand is too round and smooth. What you need is coarser grained; sharp sand (or builders sand). The coarse particles will bind the clay.

The other material used in construction is Straw (and/or Wood-chip). This mix of Clay, Sand, Straw, also known as Cob  has been used since the beginnings of time to make buildings. This video about Shibam, so-called Manhattan of the Desert, shows the power Cob in action. In the oven the straw is principally used for insulation.

Put these together with some Refractory Bricks, and you can make a domed oven, that looks like a bit this one I made earlier-

You might ask yourself, "Why would I want to build one of those? I have an oven in my house." To which I reply-

• Communal activity, both in its construction and use. Couldn't you do with a bit more quality time with people? 
• Your indoor oven doesn't cook like this oven does. (see next post)
• It is very hip and people will charge you £1500 to build something equivalent but not as treasured as the one you could have made. (If you do want to pay someone to build an Earth Oven for you please get in touch I wouldn't charge anywhere near that.)
• When Civilisation has collapsed how are you going to bake without gas or electricity?

.....Next, a short digression into heat, then back to construction with an overview of the building process.

Toodle pip!