Build a fireplace out of concrete

Problematic concrete

Conventional concrete is one of the types of stone that is not sufficiently refractory. The stone itself can withstand heat well, but its ability to soak up water is problematic. Concreted outdoor fireplaces are exposed to wind and weather and, of course, rain. The moisture seeps into the concrete - only to evaporate or evaporate as soon as the fireplace is lit again at the next opportunity. even to fizzle out. The consequence is that the concrete bursts and concrete blocks (as well as Ytong blocks, but because of the air they contain) can even explode in the worst case. For the same reason, the foundation of a fireplace should not be concreted either.

Concrete fireplace ideas

If you still want to use concrete for your fireplace, the stone must be protected from rain and moisture. This can be done, for example, by a

canopy happen, but also by a cover with a water-impermeable material. If these requirements are met, you may not necessarily be able to line the fireplace yourself with concrete blocks, but you can use them for the border. For example, disused manhole rings of various sizes are very suitable for this. You are absolutely on the safe side if you use fireclay bricks for your fireplace, because they are completely fire-proof. Fireclay bricks are specially made for lining chimneys and blast furnaces and must therefore be able to withstand high, direct heat.

Refractory concrete

There is also the option of using refractory instead of conventional concrete. So-called refractory concrete can withstand temperatures from 1,100 ° C to 2,000 ° C and is therefore perfect for concreting a fireplace. By the way, you should have one brick fireplace plan, the use of refractory mortar is recommended - otherwise the wall could not withstand the great stress caused by the heat.