Natural stone in firebox

[Kevin Austin]

Hi all,

I have a high end client that insists on some kind of natural stone in the firebox. He likes the old cooking fireplace designs from the 1800's. Attached is a drawing. I've got about 60hrs of research that has led me to sandstone from Ohio. Seems it has some good refractory qualities. (Used in blast furnaces in 19 century)

The client would like to use the stone that is on the outside of the house, (Sericite Schist...Mica and Feldspar I think), but there's not much info available about it.

Anyone have any experience here?

Thanks,
Kevin

 

[fraxinus]

Hi Kevin,
I have absolutely no personal experience in this area, but there are 18th and 19th century fireplaces in this part of Maine with granite block lined fireboxes. Perhaps in areas where they were common, soapstone and bluestone were also employed. I would think that any dense stone without a tendency to split would work. Any schist, because of its well defined cleavage planes, would, I think, tend tend to split and spall as a result of thermal stress.

 

[savageactor7]

Be careful choosing the correct stones...most will crack in fire. Besides the fact that fireplaces are so inefficient to begin with.

 

[Cazimere]

When i was young living in the mountains of PA, we used to camp out and build fire pits with sandstone.
Sometimes with a very hot fire the stones would crack and even cause minor explosions.

 

[begreen]

Granite was the first stone I thought of. I'm not sure about sandstone. If there is any trapped moisture in the stone it has a possibility of cracking or popping.

 

[woodburn]

Not sure either, but some natural stone will EXPLODE! Be careful

 

[fossil]

Think I'd use Iron ore...processed into steel plate. It's all gonna be black soon enough anyway. ;-P Rick

 

[InTheRockies]

Anyway you can talk your client in to a large stove alcove to house a wood stove? It would be more energy efficient and you wouldn't need to worry about the affects of exposing the stone to a direct fire.

I'm the third owner of a small home (1200 sq. ft.) that I would characterize more as a cottage. The husband of the second couple who owned this house was a retired stone mason. He designed and built a stone alcove on the south-facing, outside wall of the great room, which is the living room area. It looks like an old-fashioned walk-in fireplace--it's over 4 feet high inside. Here's a link to a photo to give you an idea. I love it--it retains heat from the stove and radiates it out at night--on sunny days, it also collects solar energy (although we don't get as many sunny days in the winter).


(broken link removed)

If your client insists on a fireplace, the stone should do fine. It will stain, like any material directly exposed to fire. My paternal grandfather built his own stone fireplace and it's still used by the current owners of the house.

 

[Kevin Austin]

Thanks for the replies everyone!!

 

[dvellone]

I would check on the composition of the type of stone he wants to use and check each element's stability at high temps. That should be fairly easy info. to find. If the stone's formation was resultant of high temp. such as granite, it can certainly tolerate the temperature of a fireplace. Think of pottery and it's temperature tolerance based on the temperature it was fired at. The problems associated with granite at high temperature (rupturing or exploding) is usually the result of moisture trapped in the stone. You can avoid these problems by avoiding "river rocks". I've built drystone outdoor barbecues and fireplaces using granite and have had no problems with rupturing. You might also explain to the homeowner that some insignificant flaking may occur but won't affect the overall quality. And of course you probably already know that fireclay or refractory cement is necessary for sound joints.

 

[dvellone]

By the way... very nice design

 

[gpcollen1]

Looks good - I wish I had that. Some folks said he should install a wood stove but that makes no sense here. He is obviously going for a look - and hopefully the functionality of being able to cook in and around the fireplace too. I have a plain old fireplace that i cook in and I love it. I could only dream of all that space to swing a pot over the fire or a huge hearth where you can roast a turkey.

As for the stones - I am sure every stone imaginable has been used at one time or another. I think the big no-no is any rock that can have water trapped in it - like slate/shale. Granite should be fine. Sandstone will flake and wear down I think.

 

[Adios Pantalones]

Lots of low break in fires... most hard stones would suffice. Watch out for calcining- some stones will become brittle as some materials are driven out by the heat.

 

[woodburn]

AP- What do know about sandstone? I used it for the hearth beneath my stove. You don't think it will crack do you?