The best solution to protecting cob buildings from heavy rain is a good roof with a wide overhang combined with a high foundation to protect the bottom of the wall.
Cob oven roof.
They showed me around their fabulous cob creations not to mention plying me with vinho frisante and humous.
Once the perimeter of the roof was covered with sod we covered the rest of the roof.
Whereas the second layer thermal insulation of cob mixture consists of clay sand straw and water.
A cob pizza oven dome is a basic structure built out of a combination of mud sand water and straw.
Building the living roof.
If you want to build a close replica of our cob oven here are the materials you ll need.
Since i already wrote about cutting sod for my roof i will describe how the sod was loaded.
We have access to good lime sand renders for sealing is this sufficient to avoid moldy walls.
So the first layer thermal mass of cob mixture consists only of clay sand and water.
Cob ovens use clay mixed with sand for the thermal mass and clay mixed with sand and a large amount of straw as an insulating layer on the outside.
1 pallet of rocks or urbanite go select attractive rocks that match your design aesthetic concrete for footer ask person at home improvement store to get you enough concrete rebar for a 62 x 62 slab.
About 40 of rain yearly much in the form of snow which is on the ground november april.
Does my cob oven need a roof.
For a first time builder a yurt style roof like cyric30 suggested would probably be easiest.
The dome is constructed over an oven hearth which is created from cob stone slabs brick or fire bricks.
Fall and spring tend to be wet periods we ll get a week or two of rain dampness at a time with no real chance for.
Some folks will add a true insulation layer between the inside and outside layers using a variety of materials such as sawdust perlite and vermiculite.
Take a look at this wonderful cob oven with cob seating area frenk and nicole built.
For a 27 oven you ll need a foundation much larger than that however.
Doing the edge was the trickiest part since i had the fold the epdm underneath itself and leave a little bit exposed to protect the edge logs.
But that s not the half of it.
The area containing the cob oven and seat isn t protected from the rain.
Posted 7 years ago.
In building an oven dome we need to have a thermal mass layer and a thermal insulation layer to hold good heat for baking.
Factor in another 8 for the cob dome itself 4 thickness around the entire sand form 16 for insulation 3 for plaster and another 4 for the diameter you may lose as your foundation grows taller and tapers inward.
You would place a bond beam at the top of the cob wall ideally concrete and rebar or alternatively airplane cable connecting all the members of the roof in one big circle they way the roof is designed is to act in compression while exerting force on the bond beam which will act in tension.
