Building your own low-tech wood burning pizza oven

Building your own low-tech wood burning pizza oven

Building your own low-tech wood burning pizza oven is a substantial undertaking.
But the whole process can be reduced to a series of small steps. And you don’t have
to build the whole thing in a weekend. It is built from the ground up, starting
with the base, the cooking surface and then the dome. This wood burning pizza oven
can be built on any flat site, or even on a terraced bank of earth behind a
retaining wall, as long as it is well compacted and drained properly.

An outdoor pizza oven is built with a raised, solid paver floor supported at a
comfortable working height. The massive floor provides a ‘heatbank’ in which the
heat of the oven can be stored. While the supporting base could be built of various
materials, bricks or masonry blocks are ideal.

As this low-tech wood burning pizza oven is principally unfired adobe, it is not
weather-resistant and will need to be sheltered from the rain. This can take the
form of a plastic or vinyl cover, similar to a barbecue cover, or a small skillion
roof can be built over the oven.

Gather your supplies
  • 0.2 cubic metres of ready-mix concrete or concrete mix
  • Old floorboards or framing timber for formwork
  • 1400 x 1200mm piece of F62 steel mesh
  • 37 masonry blocks, 400 x 200 x 200 mm
  • 2 half blocks for base (see Diagram A)
  • 3-4 bags of mortar mix
  • Flat 1000 x 10mm thick galvanised steel lintel
  • 4 lengths of 32 x 32 x 4mm or 50 x 50 x 6mm x 900mm angle iron
  • 1000 x 800 x 12mm compressed fibre cement sheet
  • ¹⁄³ cubic metre decomposed granite or similar
  • ¹⁄³ cubic metre brickie’s sand for oven floor and sand mould
  • Smooth bricks or clay pavers for oven floor and skirt
  • 40mm-thick tiles or pavers for oven surround
  • Air-setting mortar or fireproof cement
  • 32 or 16mm exterior grade plywood (2 or 4 of 300 x 500mm)
  • 900 x 112mm diameter stainless steel flue pipe (4½” is fine)
  • Half wheelbarrow of clay or bags of powdered clay
  • Half wheelbarrow of crusher or stone dust or 5mm minus aggregate
  • 1-2 bags cement
  • 500mm sisal rope
  • 100 litre bag of vermiculite
  • Plastic drop sheet
  • Temperature gauge, 0 to 500ºC, 75mm dial, 300mm probe
  • Bondcrete (optional)
  • Oxide colouring (optional)

You ’ll also need

Wheelbarrow; jigsaw; angle grinder with metal cutting disc; spade or hoe;
brickie’s trowel and float; rubber mallet; bucket and sponge; garden and
kitchen sieves; measuring tape; straightedge and spirit level; hammer;
screwdriver; safety goggles, ear muffs and dust mask; broad paintbrush

LETS START BUILDING OUR WOOD BURNING PIZZA OVEN!

Step 1 (see Diagrams A and B) Pour a 1500 x 1300 x 75-100mm deep concrete
slab in formwork made of old floorboards or framing timber. This is easiest if you
order a small quantity of ready-mixed concrete once the formwork is prepared. To
limit cracking, include a 1400 x 1200mm piece of F62 steel mesh in the centre of
the concrete. Once the concrete has set, keep the slab wet to cure it properly.
After 3-4 days, build a 1400 x 1200mm base made of 400 x 200 x 200mm hollow
concrete blocks. Build up the first 3 courses as shown.

Step 2 Install a flat 1000 x 10mm-thick galvanised steel lintel over the opening
and 4 lengths of angle iron across the opening as shown in the diagram. You will
need to grind off small vertical sections of the steel angles of each end so they
sit flat on the blocks. Add the last course of blocks.

Step 3 To support the thick oven floor, insert a sheet of 12mm compressed fibre
cement onto the angle iron to form a well. You could also pour a suspended concrete
slab but this would need formwork on the underside and reinforcing. Fill the
hollows of the concrete blocks with concrete (with 5 or 10mm gravel size) or stuff
paper into the hole of the top block to only fill the top 100mm or so.

Step 4 Lay a bed of decomposed granite (granitic gravel with some clay content) to
the level of the top of the blocks. Pack this down well so it is hard. Avoid using
sand as it tends to shift and not pack down well. The function of this thick bed is
to absorb the heat while the oven is heating up but it also retains and returns
heat to the oven once the fire is out. It is especially good when baking
bread or cooking roasts.

Step 5 Once the decomposed granite has been packed tightly into the well, spread
and level a 10-15mm-thick layer of brickie’s sand over the surface as a level bed
for the oven floor. This is easy to do by placing a 10-15mm batten each side of the
well and use this as screeding rails. The sand can extend a little over the block
work. Then straighten the edges.
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