Sean's Oven

[spbarr]

Hey everyone,

I started my oven last weekend; we have the slab poured and the first course of brick down. This weekend we are planning to lay the rest of the block for the walls and pour the hearth.

A thing to note...
When we poured the slab we leveled it but did not completely finish it. We made the mistake of returning the mixer and it took longer than expected. By the time we returned the concrete was already too hard to smooth out. It’s ok since no one will see it. I will say we were attempting a rustic look .

More pictures to follow.

-Sean

[spbarr]

One question, for the hearth should I use Vermiculite or FB board? If I go with FB board how does it stick to the hearth?

-Sean

[dmun]

Hi, Sean.

The vermiculite concrete should be four inches thick for proper insulation. Cal-sil (FB) board will work at a two inch thickness. I used a mineral wool product from HW, insblock19, which came in 2.5 inch thickness. I laid the board down directly into the wet concrete of the support slab, and it worked well. The Cal-sil board has a tendency to soak up water, and will suck the moisture out of your concrete if you apply it directly. It has been suggested to place vapor barrier plastic over the wet concrete, and put your boards down, that way you can thump them into position, and get a good match between the surfaces, but the board won't effect the concrete.

There is also a refractory adhesive sold in tubes for caulking guns, but I don't think many people here have used it. It's expensive.

[Frances]

From what I've heard (being a vemiculite hearth insulator), the FB insulating board sticks to the hearth by gravity. Put it down, build an 800 kg oven on top... it won't go anywhere...

[thebadger]

agree 100

I just put my FB board down - no adhesive. Trust me - it's not going anywhere.

Dick

[DrakeRemoray]

Great to see another oven started. Where are you in CA?

[cplain]

Sean

From your pix looks like you're building an extension to the right...will that be prep surface? or grill?

Craig

[spbarr]

Dmun, Frances and TheBadger:

Thanks for the reply, it sounds like FB board is the recommended way to go? If I go with FB board should I pour a 3.5" hearth still or go a bit thicker?

Also another question what mortar should I use for the oven?

Drake,

I'm in Walnut Creek CA

Cplain,

I am planning on it being a prep surface.

Thanks all for the responses; I am hoping to be curing the oven in a few weeks!

-Sean

[PizzaJNKY]

For the mortar, I would go with Refmix. The stuff is easy to work with, and is rock solid.

[carioca]

Originally Posted by dmun

<snip>

There is also a refractory adhesive sold in tubes for caulking guns, but I don't think many people here have used it. It's expensive.

Hi dmun, do you happen to know name/brand of such adhesive? I need exactly that to 'glue' together two halves of my oven door ( the one that doesn't have any touching metal parts but is held together by the insulation)...

Cheers,

LMH