Granite countertop installation questions Pompeii Oven Construction Discuss Granite countertop installation questions in the Pizza Oven Design and Installation forums; I had a piece of granite cut for my oven. The attached image shows the cardboard template I used. I ...

[sjmeff]

I had a piece of granite cut for my oven. The attached image shows the cardboard template I used. I have two questions regarding the installation:

1) What should I use to fill the gap between the granite and the exterior of the oven? I have some high temp caulk that I'll use for the gap between the granite and the firebrick, but I'm not sure what to use for the other gaps (e.g. the brick arch and stucco).

2) I'd like for the granite to have a slight pitch so that any runoff will flow away from the oven. I don't want to simply use shims, as I understand that granite needs to be fully supported underneath. Ideas?

Thanks,
Stephen

[Neil2]

You might consider using no gap filler at all. The heat produced is going to cause all kinds of movement and it is hard to believe that any kind of caulking will not eventually fail.

It is a good idea to fully support the granite. Simply shim to the level you want and then lay a bed of mortar.

[dmun]

I'd fill the gap with wood ash. It's cheap, heatproof, and constantly renewable.

[sjmeff]

Thanks for the responses. I assume you both mean the gap between the firebrick and the granite. Is that right? What about for the gap between the granite and the outer arch and stucco? I thought that I should use some kind of water resistant sealant so that water doesn't get under the granite, but perhaps that's not needed.

[dmun]

If you are adhering your granite slab with silicone caulk, the usual way, there should be enough to keep water out of the crack. I'd keep it well below grade, though. It's supposed to be heat resistant, but I don't think I'd want the stuff near heat and food.