one season and the firebrick is cracking... help!!!

[knifehead]

i noticed that my firebricks been cracking after only a couple dozen fires. i know your not supposed to have the fire directly on the brick but after the wood has been burning for a while it just falls off the andirons....and i dont like the look of grates so here is my question.... could i possibly get a thick slab of bluestone and place it over the hearth floor and have the fire on that??? any ideas or suggestions will be much appriciated.
mark

 

[Corie]

The blue stone is an awful idea.

Cracking firebricks on the floor of the firebox sounds like a problem because they should be fully supported from underneath and almost shouldn't be able to crack, except due to heat cycling.

Andirons? Grates? What stove are you burning?

 

[BrotherBart]

Sounds like an open fireplace to me?

 

[knifehead]

yes, it is an open fireplace.

 

[elmoleaf]

How old is the fireplace? Recently built and cracking after only 24 fires?

A couple possibilities:
1. They're not firebricks.
2. The firebricks were improperly installed.

Your problem has a couple of solutions, but it'd be wise to first find out why they're cracking. Perhaps there are other issues with your fireplace that need to be corrected.

 

[Burn-1]

Is this a new fireplace? If so it sounds like you might not have done proper break-in burns to finalize the curing of the firebox and chimney. If you had a large fire as one of your first few fires that would probably do it. I think the bluestone would probably be OK but another option would be to buy some castable refractory cement and pour a small slab. You could probably easily make it form fitting to the fireplace floor. A fireback might help if you have some craks in the back section of the firebox.