"A cob oven costs almost nothing to build and produces a pizza no commercial oven can match.
"KaiRenner26th of April 2026
Building a Backyard Pizza Oven from Cob
A cob oven is built from clay, sand, and straw. With a proper foundation and dense cob dome, it retains enough heat to bake multiple pizzas and then bread as the temperature drops. Natural, durable, and beautiful.
900F
3Days
Build the Foundation
A rubble trench or concrete block base elevates the oven to comfortable working height. Top with a layer of insulating cob or vermiculite concrete before the firebrick floor. The floor must be level and hold heat.
Form the Dome
Build a sand form the shape of the interior dome. Lay cob in layers over the form. Inner dome diameter of 60 to 80 cm is ideal for a family oven. Let each layer dry before adding the next.
Add Insulation
A 10 cm layer of insulating cob or perlite and clay mix over the structural dome dramatically improves heat retention. Finish with an earthen or lime plaster outer shell to protect from weather.
Build Checklist
Foundation complete and level
Firebrick floor laid with refractory mortar
Sand form shaped and wetted
Structural cob dome completed in 2 to 3 layers
Dome dried for at least 48 hours before removing sand
Insulating layer applied and dried
Plaster finish applied and cured
Do not rush the drying between layers. Cracking from moisture trapped inside is the most common cause of dome failure. Small cracks are normal and can be patched.