Concrete bricks

[John McMillan]

For the last month I have been building a large wood oven, I live on a small island in Norway and had trouble in finding correct materials. I have just found out that I have used concrete based pavers in the dome and walls instead of red clay brick. I had to use these as the cost of fire bricks are extremely high and could only afford to use them on the floor.

Is there any way to correct the problem, will it be dangerous to use oven as it is?

[Gulf]

John,

Welcome to the forum. I'm sorry, but the concrete pavers will not hold up to the extreme heat. I'm not sure that there is anyway to correct it without taking down the dome and replacing it with a suitable material. Can natural clay be found on the Island where you live?.

[SableSprings]

Welcome John! As Joe stated above, the concrete pavers will eventually fail as concrete starts to degrade at under 450. Did you look at natural rock as an option. Granite is very heat resistant as are other natural stones. It seemed to me that Norway had quite a good supply of metamorphic rocks (like granite). I remember walking down a street somewhere in Scandinavia that was paved with what looked like 10 x 10 x 10 cm granite cubes. I hate to admit it, but the first thing I thought of was "I could build an oven with that!" I personally feel that a stone oven would work well as long as you used solid pieces held together with home brew...hopefully

Anyway, I suspect Joe's looking at the option of building a molded clay oven on your existing cooking surface. Have you checked on the availability of builder's lime through a construction supply business and fire clay from a pottery supply shop? There are several builds on this forum where they have made molds and cast their ovens...some using standard home brew--although better materials are available. It would be an interesting option to look at -- if rebuilding with granite or clay doesn't sound good to you. Here's a link to a short explanation of refractory concrete mixes and castable materials.

http://www.traditionaloven.com/tutorials/concrete.html

David S is our resident expert on casting an oven and hopefully he'll chime in here (especially if I'm wandering off base ). david s

[Toomulla]

If you have built it use it till it fails

[John McMillan]

Thanks for the replies. Still considering best way forward. At moment looks like partial take down and rebuild will be best as it would be a lot of work later if I used it till it failed. Use of granite may be a way to go as that is much cheaper than fire brick here.