If this is a new home it could be some sort of settling problem.

Mine just cracked in 2 places after burning off new fireplace oil. Its junk now. Don't do it!

Hi @uyenduc, what ended up happening to your marble? Did you find out if it was install job of the fireplace insert or the marble installation? Thanks.

This exact thing happened to us recently. One large slab of 2cm Carrara Marble cracked in 2 places and up through the mantel. Linear gas direct vent fireplace. We just started using it and had not even turned it on more 6 hours total so far. Within the first 2 uses it cracked. It is so upsetting. I would like to know what solutions/fixes you all found. thanks

We just installed a quartzite fireplace surround. 1.25 inches thick. Two pieces stacked. First 30 minutes vent free gas go and two cracks extending from the corners of fireplace. Any ideas or help please ??!!

Pdefrancesco - I’m so sorry you are also dealing with this!!!!
We could not find someone to repair it, plus we expected that it would happen again once fireplace was turned on.

What brand/style is your fireplace? Ours is a Superior DRL3054. It gets extremely hot. After lots of investigation we determined it needs 2 layers of special hardiebacker board (vs. 1 layer) and a heat shield. Manufacturer recommended to turn the gas line down to 70%-80% so that it didn’t get as hot. Also that the front area around our fp with cracks should be replaced with 4 pieces (instead of 1) to allow for seams that will give a little when heat causes expansion. Not the design we wanted or planned on, but will live with it.

Dawn Hood - curious if you replaced your stone with the solution you noted here. I just had marble installed on new 48” direct vent gas fireplace and after first hour of use the marble cracked. The fabricator was originally going to put 4 seams but did not put any and now I’m wondering how much harder board we have and what the heat shield is and if we have that - will have to ask my GC.

Our house was built in 1964 with a double-sided marble fireplace. Each face is built with three pieces of marble; one across the top, and one along each side. The hearth is raised and also three pieces. This is the original fireplace and no cracks are evident anywhere. When it is used the fireplace stone gets really hot and is still warm the next morning.

Our new custom build has two 4-piece slab fronted linear Flare gas fireplaces with direct venting and “cool glass”. One of them - Sierra Noir marble - cracked from ceiling to floor along one of the returns BEFORE it was even used! It turned out the chase was poorly constructed and didn’t support the stone properly. Our contractor refused to take responsibility, but his stone fabricator paid for replacement stone and had his installers rebuild the chase properly, all at his expense. He intended to pursue the contractor, himself. Since he is considered the best and most sought-after fabricator in the region, I imagine the contractor has paid more than just monetary compensation for his incompetence and unprofessional attitude; I assume he has lost a valuable sub-contractor and his reputation in the industry has been damaged, all of which is richly deserved.

Tricia - we pulled off all of the damaged marble and added a second later of Hardibacker. There was not enough room for the heat shield so it did not get installed as I had hoped. FP Installer and my GC worked together to replace the marble. No expense to me. I am very thankful.

We reinstalled the single slab with 4 pieces. (a new single slab cut into 4 pieces so that the seams could "breathe" and not crack)

@Dawn Hood How has your marble surround held up since it was replaced with multiple pieces rather than one?

I decided earlier this week to go with a marble surround for my fireplace, changing direction from my original plan. I'll be using River Blue (swoon).

Anybody offer some help with this one please? This fireplace wood burning stove was installed in 1997 by the builders. I bought the apartment two years ago and found a load of firewood in the garage so presumably it had been in use, though I haven't lit it yet myself Last year the apartment was rented out. The crack and the blue stain are new. Now I don't know if it's safe anymore to use and if there's any remedy (for either a crack that size or stain). The top stone has shifted forward a bit, away from the chimney wall