Makeup for outdoor BBQ/fire pit

[djcdan]

I am currently in the midst of an outdoor kitchen project, but am receiving conflicting information on the net about materials to use in the fabric of the BBQ/fire pit planned.

We'll be having an open grill with direct heat on the base of the BBQ area just beneath the grill. I would like to line the bottom, sides and backsplash in a black coloured natural stone - I'd been looking at granite offcuts from our local supplier. However, there is conflicting information whether granite can take the temperatures generated by wood/charcoal embers. I would be black firebricks as a backup option but in 220x110 blocks it would look overly fussy and would prefer a single slab of something purely for aesthetics.

 

Beneath the slab/firebricks which will be taking the direct heat, I feel as though I need an insulation layer as a barrier to below (which is blocked and stone cladded). I have come across Ceramic Fibre Insulation board, however the only viable supplier of this charges an absolute fortune to deliver just the one sheet needed on a pallet to my location! At the same time, the information on the net isn't conclusive that this is the right material to insulate and have also read the material has been linked to health and cancer risks.

 

Therefore my question is two part:
i) Do you think it would be suitable to use a natural stone directly against the heat, if so which. If not, what alternative would you suggest?
ii) What material should I be using beneath as an insulation barrier?

 

TIA
 

[George]

Natural stone is likely to crack from the thermal expansion and contraction fracturing any discontinuity in the stone.

 

If you don't want joins then cast refractory concrete died black should work. The sides could be black stone so long as they're not in direct contact with the fire. 

 

I don't think there's much point insulating an open fire. Only really makes sense for pizza oven type set ups

 

 

 

[djcdan]

17 hours ago, George said:

I don't think there's much point insulating an open fire. Only really makes sense for pizza oven type set ups

My reason for insulating would be that the stone cladding - which would be applied just below the BBQ base on the face of the block - is adhered to the block using mortar. Would mortar cope with the potential heat transfer?

Edited December 7, 2023 by djcdan

[Andehh]

Wonder if you could use porcelain tiles?? They come out of a kiln... Though IANAL

[kandgmitchell]

I spent ages building a brickwork BBQ - made an arch former and incorporated a lovely arch feature in the base. Used a really old, thick concrete paving slab as the top, where the charcoal sat. Built a brickwork perimeter off that where the grills could slot in. 

 

The first time I used it the slab cracked completely through front to back and shifted the perimeter brickwork. Ho hum!