What causes firebrick to crack ?

[laynes69]

I'm thinking about soapstone in mine. I don't have that many to replace. Price is about 2 - 3 times what cheap Rutland bricks are, but I bet they will last more than 3 times as long. Trying to decide if the thermal properties in my stove would be worthwhile.

I've heard of soapstone's cracking when a stove gets too hot. Placing them inside a firebox may be an expensive mistake. Standard firebrick are pretty dense and will take the heat.

 

[740jsmayle]

Are all firebrick the same quality regardless of what name they are sold under ?

 

[BeatCJ]

I've heard of soapstone's cracking when a stove gets too hot. Placing them inside a firebox may be an expensive mistake. Standard firebrick are pretty dense and will take the heat.

I'm not impressed with the standard brick I was able to buy for my stove. I do understand that they are exposed to extreme conditions. I would suspect that soapstone will stand up to the same conditions, though. I know it is used to line fireplaces and stoves. I would bet it, like commonly available fire brick is most likely to crack during rapid changes in temperature.

Are all firebrick the same quality regardless of what name they are sold under ?

I doubt it, but I couldn't tell you which (if any) brand is better than another. I would doubt the least expensive, most common brands (Rutland and Vogelzang) are the better bricks, but they are what is available.