RSF Opel 2C - Hearth Material and Firebrick

[koselig]

Hi all! Two questions, very excited to fire up our Opel 2C:

1. The hearth "seat" is a quartz material (Cambria). We have had quartz in previous kitchens but never a fireplace like this. How hot does the black steel on the front of the unit get below the vent where it is in contact with the hearth? I have heard because the fireboxes in these are so well insulated, that the majority of the outside surfaces are never dangerously hot except for the doors and the immediate perimeter of the doors. I am hoping not to have to worry constantly about the material getting damaged. We were originally going to put soapstone here, but while choosing countertops it seemed elegant just to put the same here. I wouldn't set a hot ash bucket on there, but I wouldn't have done that with soapstone either.
2. The firebricks seem to fit together loosely. Is this intentional? They aren't all "aligned" and straight, but I am guessing this might be normal. Wanted to confirm in case anyone has advise or I should check something before first burn.

Thanks!
Patrick

 

[koselig]

I am fairly certain we will be OK on this, but any info from anyone with an Opel, or with a quartz hearth/surround would be much appreciated! Cheers, all.

 

[begreen]

Cambria is not ok for a hearth due to the resins that bind the quartz. It should not get over 150º. Radiant heat from the fireplace can get hotter and an errant ember can be much hotter.

DOES CAMBRIA WITHSTAND HEAT? CAN I PUT A HOT PAN OR POT ON IT?
Cambria may not withstand the direct transfer of heat from pots and pans and other cooking units such as electric frying pans and griddles, slow cookers, roaster ovens, and heat lamps. Therefore, the use of a hot pad or trivet is always recommended to prevent heating the product.

Cambria® Quartz Countertops FAQs

Explore frequently asked questions about Cambria natural quartz countertops and surfaces. Learn about Cambria, countertop installation, product care, and more.

www.cambriausa.com

Cambria is not heat proof, chemical proof, or fracture proof in any form. Be aware of exposure to these potentially damaging acts.
(broken link removed to https://www.cambriausa.com/product-care/#!/)

 

[koselig]

in case this is useful to anyone, I specifically asked the fabricator who works closely with Cambria, which is a "local" product to us. There are certain things they are directed to do by Cambria such as am 1/8" gap to "insulate" the material. Especially with the hearth where is it below the vent which itself is below the firebox, it should be OK. He said they also use it to surround fireboxes, and there is a protocol for that as well.

The issue with setting hot pans on quartz is the temp differential between ambient and the pan which could be 400+F, whereas on a fireplace the temperature is consistent (except for a hot ember of course). So I think we will be fine. I will report back in case anyone is interested!

 

[begreen]

While it looks like it would be ok with the flush fireplace on the sides, I don't think it should be used for the hearth. There is no protection from the direct radiant heat off the door. It is a plastic resin product. The contractor's explanation doesn't note warning of the lower temps from roaster ovens, heat lamps etc. that are mentioned. It might be ok for a gas fireplace insert, but not wood. Remember, the contractor does not have to live with the problems, the homeowner does.

From the product guidelines:
When Cambria is used for applications with a unit that emits extreme heat, Cambria must be installed as a combustible material under the manufacturer’s guidelines.

https://p.widencdn.net/s55slg/Approved-Statement---Surface-Burning-Characteristics-and-Fireplace-Applications

Combustible materials are not permitted for the hearth per the Opel 2 manual.
HEARTH EXTENSION
The area immediately in front of the fireplace must be protected by a non-combustible material such as brick, tile, stone, or slate. Refer to Table 1 (G-H) for the depth and width that the hearth protection should extend beyond the front and both sides of the door opening (see Figure 1). There is no minimum thickness required for the hearth extension.