Wood-Fired Oven ~ Hearth Foundation

After last winter, our first order of business in May was to create a wood support for the hearth. Although it is to be a suspended hearth, we built a center pillar with cement blocks to provide additional support. The pillar top had to be in the middle of the hearth insulation layer so we had to build up the height a bit. Unfortunately, the corner broke when we removed the form, but it will not affect anything as it will ultimately be inside the insulayer layer.

The bottom of the insulation layer is build with pieces of plywood we recycled from the yard; we could have done it in only 2 pieces but the smaller pieces meant for easier removal.

At the far end of the photo,you can see we built a shape to create a void for the ash slot; you will see it better in the next steps. The ash slot will allow me to rake the ashes out of the oven and let them fall under the base; much easier removal.

At the forefront is the wood frame that will be used for the next step: the hearth slab, and the grooves at the top of it will support some rebars and create a 1" air gap between the hearth slab and the cement block walls, so that the hearth slab has some room for expansion. It's easier to prepare for the next step right away because the hearth slab should be poured the same day as the hearth insulation layer to help the bonding between the two layers.