Misadventures in woodfired pizza oven construction

Preamble

A wood fired pizza fresh from the oven.

Having developed a bit of a taste for classic Italian style pizza from various local SW London pizza restaurants* when I lived in the UK, I, (with some words orders of encouragement from my wife) am attempting the build an oven in my garden.

A few people have been asking about my construction process so I thought I'd put this page together to assist anyone thinking of building a pizza oven themselves... so that you don't make the same mistakes I did!

Just to forewarn you, I have minimal construction or DiY experience and things may go horribly wrong. If you maim or kill yourself doing anything I suggest below you've only yourself to blame.

*If you're ever in London make sure you go to either of, or both of, Franco Manca and Donna Margarita.

Stuff you'll need

Ordinary bricks Fire bricks Breeze blocks Brick bolster Brick laying trowel
Rubber mallet Spirit level Concrete Mortar Wood
Chicken wire Plastic sheeting Rubble or hardcore Saw Nails
Grinder & brick blade Vermiculite Notepad and paper Ruler Calculator

Choosing a site to construct the oven

Make sure you choose a well sheltered corner. You may be tempted to build it near where you plan to eat if you like to dine al fresco - just be aware that these things can put off a bit of smoke which may make being near them a bit unpleasant. But having said that if you're entertain guests at a table near the oven it's quite exciting watching the cooking process!

Constructing foundations

All up your wood fired pizza oven will weigh about a ton so you'll need a solid base to support all that weight. It's also going to make your life considerably easier when you start laying bricks if you're laying them on a level surface.

To build my foundations I dug a hole about 200mm deep in the garden filled it with rubble and then poured concrete over it. The surface I made was 1200mm square (this size will be handy later when you're laying your breeze blocks which are 400mm long).

The base

Starting to lay blocks on the foundation.

If you don't want to have to keep bending to ground level when you are cooking you will need to create a raised base. I built my base out of cinder (breeze) blocks. Building up only three sides allowed me keep an access to the cavity under the oven so I can use it as wood storage later.

Top of the base

Timber structure to support weight of slab.

To create a surface to start constructing an actual oven I built a timber frame and a wood mould and poured a slab of concrete on top of the breeze blocks.

To support the weight of the slab while it was being poured I built a wooden frame inside the cinder block walls and lined it with chicken wire and then plastic sheeting into which I poured the concrete.

Constructing the oven

Base with bricks arranged in rough shape of the oven.

Here's where things start getting a bit more difficult. You'll want to mark out circle on your slab - leaving enough room for the mouth of the oven at the front - it'll look sort of like an igloo when done.

Luckily living in Christchurch post-earthquake bricks are quite easy to come by! To make it easier to construct the dome I cut my bricks in half using a cheap angle grinder from Bunnings with a brick cutter blade attached.

Cooking surface

Layer of sand to help lay fire bricks. Fire bricks laid in ring of dome.

There are two options here, you can either lay a layer of fire bricks down and then build your dome on top of them. Or, do what I did, and start laying the dome and cut the fire bricks to fit.

To lay the bricks I put down a 20mm layer of sand first this makes the bricks easier to lay and get level.

You should really use fireproof mortar for for the dome. However it's frightfully expensive so I'm using ordinary construction mortar with a little bit of fireproof mortar mixed in. This may backfire on me...

The dome

Building up the dome using a template.

Your dome needs to be a perfect half sphere in order to reflect heat from all sides directly into the centre of your oven. I cut a template of the shape I needed my dome to be and used that as I laid my bricks to keep the shape of the dome accurate.

I'm just using standard red bricks for the dome as they're cheaper than firebricks.

The oven door

Building up the pizza oven door using a template.

The height of your oven door needs to be approximately 65% of the height of the ceiling of your oven. Any larger and too much heat will escape, any smaller not enough oxygen will get in and your fire won't burn well.

I made a cardboard template of the shape of the oven door and used it to align and support the bricks used in the pizza oven door... it's a bit of a nervous wait for a month before I can remove it and find out if my door is going to collapse or not.

Top of the dome

Sand dome to help with top of dome. The completed dome.

Now it starts getting tricky. You need to support the weight of the dome while the mortar is drying. I put a couple of beer crates inside the half finished oven. Then built the platform to hold a pile of sand that I shaped into a dome shape.

I couldn't get the beer crates out through the oven door so had to burn them out later.

Then using the sand to support the bricks as the mortar was drying I finished the top of the dome.

I'm not going down the chimney road with my oven but if you wanted one for yours, now would be the time to start thinking about it.

It looks a little rough at the moment, but all my dodgy brickwork will be covered in the next step, insulating the dome.

Insulating the oven

Dome cover in insulation.

There's a bunch of theory on this next step (which I'm not going to get into too much), however the general idea is to stop heat escaping from the oven as much as possible.

Ideally you should wrap the dome in a thermal blanket before applying the insulation, but I couldn't track one down in Christchurch so just applied my insulation mix directly to the dome.

To make the insulation I mixed (while dry) Perlite (but Vermiculite would do as well) 6:1 with Portland cement, then added water to get a porridge like consistency then applied that to come dome.

Most garden centres will be able to supply Perlite in bulk, I used 4 100L bags to cover the dome in a layer about 2 inches thick.

Cooking pizza with a woodfired oven

Fire in the pizza oven. Banking the fire to the side of the oven to make space for pizza.

I've still got some cosmetic work to do on the oven, but I was hungry for pizza so have done a test pizza (or two).

To cook a pizza, first you start the fire in the centre of the oven, the inside of your dome will turn black with soot. When a 8inch circle of soot has been burnt off the top of the dome and you start to see the bricks move the fire to the right hand side (using a brush or the pizza peel) to preheat the cooking side. When the soot has been burnt off this side of the dome move the fire to the left hand side ‘Banking the Fire’ and wait for the soot to burn off. The oven is then ready to cook in.

Eating the pizza!!!

Our first pizza from the oven. My assistant chef with pizza.

Put in mouth and chew... don't forget to swallow.

Pizza oven plans

I've had a few people ask if they can download my plans for the pizza oven, so when I get a chance I'll draw them up and upload them here.

Recommended reading

Your Brick Oven: Building it and Baking in it

By Russell Jeavons

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