DIYGIY

Building a Brick Pizza Oven

From start - 

 

- to finish

 

Starting to build this Pizza Oven was a little easier because there was already the remains of an old brick barbeque which could be used as a base. You can see in the start photo that it had a press underneath and the top plinth was just extended with concrete to provide a base for an oven measuring 850mm in internal diameter.

Measurements

Concrete base: 1,400mm      -      Height of base: 850mm.

Internal diameter of oven: 850mm      -      Internal height: 500mm.

Door width: 380mm      -      Door height: 300mm 

Note:

These measurements are the minimum required for a workable oven. You can make it larger proportionally if you have the space, but remember it will cost more to build, will require more fuel and take longer to heat up.

Materials:

Most of the items used (bricks, vermiculite, thermal blanket and flue) were sourced from Dineen Refractories, Wolfhill, Athy, Co. Kildare. www.dineensales.com They also supply pre-cast ovens. These  save a lot of time and effort rather than building with brick, but they are more expensive. 

 
Building the oven

 To achieve the height of the base a row of 9" blocks were built around the perimeter of the plinth. This was then filled with old bricks and pebbles and then topped off with a row of blocks laid on the flat to provide a flat surface for the base.

A cardboard template the size of the internal floor of the oven (850mm) was made and used to position the oven on the base.

An allowance was made so that the insulated base was 4" bigger all round to act as a foundation for the brick wall. A shape for the insulated base was made from wallboard 4" deep and this was set up to ensure the door was positioned correctly at the front of the plinth.

This was then filled with vermiculite (mix 5:1 with cement) which was tamped in to provide a solid insulated base with no gaps.

The cardboard template was then used to select and mark the fireclay bricks for the base. These were numbered to make it easier when they were being laid after cutting.

The bricks were cut using a 4" angle grinder with a diamond tipped disc. To make the bricks easier to cut they were first soaked in water and this also reduced heat and dust while cutting.

The bricks were then laid on the base using mortar made from a mixture of sand, fireclay, cement, and lime in the ratio of 10:6:2:3. It is important to fill all gaps fully with the mortar and to ensure the brick base is smooth and level as this is the surface on which the pizzas will be cooked.

The next task was to build a dome-shaped sand mound on top of the bricks the same shape as the internal oven space. To achieve the correct shape a template was made as a guide for the sand mound. This was made with wall board and a steel rod attached for rotating it around the base. A hole was drilled in the centre of brick base for the steel rod.

It is important not to wet the sand too much as it needs to maintain the shape without collapsing. Pack the sand in layers on the brick base and swivel the template around to ensure an even dome shape all round.

As you can see, at this stage a temporary roof was erected over the sand dome to protect it from rain. The dome was then covered with layers of wet newspaper to form a barrier between the sand and the bricks.

The first round of bricks were built on their edge and this provided a good seal inside with the brick base. Care was taken to ensure that all joints were filled with mortar, and no gaps were left on the inside between the bricks. A shape for the door was made to allow the bricks to be arched at the top and a base formed for the chimney flue. The remaining rows of bricks were build with half bricks which made it easier to form the curved shape.

Bricks were cut as required to build the top of the arch and support the chimney flue. When the structure including the door and flue was completed the surface was covered in a layer of "sloppy" mortar and covered with a thermal fibre blanket which ensures heat retention within the oven.

 This was then covered with wire mesh (chicken wire) and then covered with a layer of vermiculite plaster.

At this stage all the sand was removed from the inside and after leaving it for a few days to dry out a small fire was lit inside which helped to burn off any newspaper which was still stuck to the brick mortar. As the oven warmed up it was impossible to resist the temptation to cook the first pizza and a home-made peel was made to handle it.

I know its hard to be objective but this tasted like the best pizza ever made. The only problem was that it was too small and second helpings were scarce.

Now that the oven was proven the next step was to cover the vermiculite layer with more wire mesh and then a scratch coat of plaster was applied. This was followed by the final coat of plaster which was coloured with a terracotta cement dye to give a nice rustic finish.

In order to conserve heat in the oven a damper was fitted under the chimney flue, this could slide open or shut as required.

Other finishing touches to the oven included a door for the front made of heavy timber and lined on the inside with tin. A sliding vent on the front allowed it to be used to retain heat when the fire was lighting.

A lead covered wooden cap was also made for the flue to keep out the rain when the oven is not in use.

The secret to using the oven is to have it good and hot. This can be achieved by good planning as it takes 1 to 1 and a  half hours to reach a temperature of 250C which is required for cooking. Lighting the fire can be tricky and it is best to use paper and light kindling to get it going and then gradually add heavier wood as it lights up. Dry wood is essential to ensure it burns well and to avoid excessive smoke.

Plenty of practice with the peel is required to get a quick sliding movement for putting in and taking out the pizza.

The secret to tasty pizzas is to get a good dough recipe (the internet is full of them especially ones for brick ovens). It is also important not to overload the base with fillings as the lighter the load the quicker the cooking time and the better the taste.

 Acknowledgements:

To my children, Orla, Conor, Eoin and Niall who once I first mentioned the idea encouraged me to get going on the project.
To my wife Kay, gofer and helper on the project who was always willing to mix the mortar and knock on the window when the coffee was ready.
To my neighbour Liam Harding who supplied the lead for the chimney cap.