Cement Board / Durock For Hearth?

[Nyxcite]

Just starting the planning of my oven, Giardino, location. The plan is to put it on top of an existing outdoor kitchen counter. I want to use 3 sheets of cement board/durock as a hearth, then super isol board, then the oven floor. Does this sound ok? Will the super isol hold the heat away form the durock? my concern is that the durock getting hot and either combusting or produce some toxic fumes from whatever the durock is made of. Using the cement board would be a lot less messy than pouring cement on the counter. Any insight would be appreciated!

[KraemerBAC]

You may have a problem with compression strength on the cement board..not 100% sure but that would be my 2nd concern...1st would be what is the counter now and can it support the weight of an oven @ roughly 2000 LBS

Peter

[Neil2]

"I want to use 3 sheets of cement board/durock as a hearth,"

Why would you need any cement board ?

Actually the term "hearth" refers to the cooking floor - generally firebrick. This sits on the insulation which in turns sits on your structural slab (in your case the counter -if it is strong enough)

[Tscarborough]

It does not have enough tensile strength to work as the slab, either cement board or hardi-backer. You can either use the poured in place methdod like most or use some precast pads like I did. Mine were 30 year old roof ballast pads, 30"x2"x30" with 10/10 6x6 wire reinforcing.

[Tscarborough]

OK, I read it slowly and I think I understand what you want to do. Do you have an existing 48"x48" area of countertop? If so, how is it supported and what is it composed of?

[Nyxcite]

Tscarborough, You got what I'm trying to do! The area of the counter is at least 48 x 48, It is a constructed of metal frame and cement board. I wouldn't think a modular oven would too heavy...?
Thanks for all of the feedback!

[Neil2]

Any photos of the existing counter ?