Project: Adobe Bread/Pizza Oven

Aim: Build a functional Bread/Pizza oven using natural materials and traditional techniques

Location: Central Portugal, Corga da Peirera

Date: December 2010

Reasons for Location of oven:
 Oven to be situated inside the covered outdoor proposed kitchen area. At this point it is only a covered area, no structures have been place there as yet, so deciding on where to locate future structures eg; sink and benches needed to be decided before building the oven

• Oven to be a focal point of area
• Possibly will have a circular bench around the oven for 'assembly line' pizza preparation or putting awaiting/cooked pizzas on to keep warm, or general bench with stools for a breakfast bar type set-up
• people can gather for warmth all the way around if it is not built touching a wall
• It's the only space in the area that can't be utilized by other things eg; benches around the edge, but just open space in the middle
• Although corner is better for space, good workbench space will be taken up, and area around the edges to gather and be warm will be lost

Equipment needed:

• Cob bricks made at least 2 weeks prior to allow for thorough drying. A clay straw mix is best, but adding soil and/or sand is also possible. Best mix is Clay:Sand:Straw 3:1:1. We made many test bricks to see which dried faster, crumbled less and were strongest. Make in a quadrilateral shape with one side shorter than the other *drawing*
• Level, shovels, rakes
• Tiles/gravel
• Rocks, smallish for the rubble filling
• Door, cast iron is best
• Long flat rock ie:slate for shelves
• If oven will be exposed to the elements, use lime in the cob mix

Process:

1. Broken tiles/gravel base a few inches thick
2. Layered rocks. Filled small gaps with gravel
3. Made cob mix, clay+soil+straw to use for mortar
4. Built ring around edge of rocks with cob
5. Laid pre-made cob bricks around 15 bricks in total for 1.5m diameter circle
6. Cobbed in bricks. Build up layers
7. Lit a fire inside to dry bricks, it was winter and wet weather. If in summer, wet each brick before you lay it, otherwise bricks will draw moisture out of mortar
8. Added a few slate shelves under where door was to be (for matches etc), and around other side for convenience
9. Once at correct height for base and once dry, filled with rubble/rocks
10. Smoothed a flat cob layer over top and let dry
11. Made a sand mound large enough to be the internal section of the bread oven
12. Cobbed over sand quite thick with the door attached and let dry
13. Removed sand via door

This was a workshop project run by Nuno Mamede. It took 2 weekends to complete with the help of 7-9 people each weekend.

Nuno chops some straw

Adobe mix

The brick moulds

Drumstick pecks away at the straw while we mix

Clay and soil

Drawing out the location
and size of proposed oven

after the layer of tiles and rocks, we started
laying the bricks

Lit a fire inside to help dry the
bricks. Level whenever possible!

Adding a slate shelf 

Ahh! Collapse!

More official photos from the completed workshop here  http://permaculturaportugal.ning.com/photo/162911475867609226683519226592-1/next?context=user