For years even before moving to the farm, we had conceived of building a wood fired oven, always admiring other effort seen in restaurants. As we enjoyed the food that came out of these amazing structures it was easy to drift off into a dream of wood fired foods that warmed the soul.
Building our oven took over 6 years. Not because a construction of this size and complexity should necessarily take so long but its true to say that when we set out to take an idea from the conception stage to reality, we definitely underestimated the complexity of the task and the
investment required.
Like many projects undertaken here on the farm, our wood fired oven was built with a vision for the future. The oven is located in a position close the house and is designed to become part of our commercial kitchen and a central feature of our house.
The design is a traditional dome built using a swivelling arm with a piece of RHS welded to some threaded bar set to a length of 75cm to create a 1.5M diameter space inside the oven by showing us where to place every single brick.
We were privileged to have a wonderful mentor and co-builder working with us, Doug Cameron from Karangi Kitchen. Doug helped to guide and advise us through the myriad of decisions that are inherent in the design, sourcing and construction phases to raise an oven from a blank cement slab.
Long before engaging with Doug, the door that adorns our oven was first conceived in 2008 when we arrived at the farm. We were introduced to Phil Hill, an old style blacksmith in Federal who used to work on the railroads and had a workshop set up in his home with giant classic machines for cutting and bending steel. When we eventually commissioned the door, the brief to our Blacksmith was to build us a door that had a boiler plate feel to it, that would look like it had been on the oven forever, allowed us to insulate the inside of the door and would hang on a purpose built frame built to create a strong support arch to help hold up the gigantic chimney arch. Almost 18 months later
we were absolutely blown away by the incredible creativity and rustic industrial solidarity of the door that was ultimately created.
The first slab and base built to hold up the oven is deeply reinforced and super strong with reinforced cement filled besser blocks to support the construction slab. The cavities created inside the outer wall was also filled with reinforcement and then included in the cement pour for the construction slab.
Interestingly the wood fired oven rests completely on a base of insulation bricks that are not cemented to the slab, this allows the small amount of regular movement that occurs as the oven expands with heat and contracts with the cooling cycle.
In order to create the clean looking internal finish of our oven, the inner edge of every brick laid is customised to fit snugly to the bricks below and next to each other. When building the dome, this was fairly straightforward for the first few rows of bricks however as we worked higher and higher it became obvious that specific customisation of every brick became required to get them to fit perfectly. This involved multiple checking visits in and out of the oven for every brick, slicing a little off on one edge, grinding a little bit off another to reduce gaps before finally feeling the confidence to mix up some high temperature mortar and setting each brick in place.
The bricks used to construct the oven are kiln bricks with high aluminium content selected for their ability to endure extreme heating on a regular basis without cracking or decay for generations. The other benefit of these bricks is their ability to conduct and retain heat.
As the project progressed and the dome took shape, it was magical to watch the slow curve of the inner walls start to form and even the bricks laid at the very top of the oven were carefully set one by one, in a way that allowed them to hold and set in positions that seemed to defy gravity. Only through working with a mentor to navigate through construction challenges did we manage to keep the development moving forward.
Once the dome was built (after cutting away part of our roof) as the oven became bigger and bigger, we reached the point where the dome needed to tie into the flue arch, door arch and decorative arch. All these differing arches and angles coupled with the engineering challenges of supporting such a heavy chimney, we again called on our mentor for the building this front section and were very lucky to receive the benefit of his knowledge and skill to complete the initial oven build.
When we fire the oven up to between 350-400 degrees Celsius, for cooking pizza, we know that the oven is going to hold a good proportion of that heat for 48-72 hours after the fire is out. To maximise the length of time that the oven holds that much heat, a number of insulation layers have been added to the oven dome, including about 10 inches of ceramic fibre wool blanket held tight with chicken wire followed by another 10 inches of strong insulation made with a mixture of vermiculite and cement. The outer layer will be another few inches of render and tiles.
Officially, we turned on the oven and started cooking in June 2015 and ran an initial market trial of cooking wood fired pizza for the local community. The result was exceptionally well received. Since then we have been testing the cooking of breads, slow cooked meats, roasted vegetables, baked goods and drying herbs and fruits.
Future plans also involve opening up the oven for the community to use on designated open days.