Does the soldier course need to be sitting on insulation?

[Jerrymontalvo]

I am building a 48 inch oven , Does the first bricks they call (soldiers) Has to be on top Of the insulation? I am insulating under cooking surface before the floor bricks, but not underneath of the structure bricks. Is that OK.

[UtahBeehiver]

The soldiers need to have insulation under them or the heat from the dome will transmit down through the hearth which will act as a heat sink. Also is there a particular reason you are using full length soldiers. The dome may require buttressing due to the inherent outward load at the dome and top of soldier joint.

[Gulf]

+1 on Russell's coments. If it were me I would lay all the courses as stretchers with the IT. That makes life a lot easier and solves a lot of problems. Soldiers only help make small diameter ovens more accommodating for breads and large pots near the edges. That is not a problem with large diameter ovens. I have a 44" oven and have yet to run out of room in it. There should be no worries at all with a 48" oven imo.

[Jerrymontalvo]

I’m using perlite and concrete for insulation And it’s 4 1/2 inches thick Under Under the oven floor. My question is, when I set the soldiers, do I set them on clay and sand mix paste, or can I set them with refractory mortar , I know they open floor needs to be set with Fire clay and sand mix.

[Neil.B]

I laid mine directly on the insulating floor with mortar.

[Gulf]

Jerry,

I started a new topic with your first post and moved the corresponding posts from another members thread. We had two conversations going on there!

....My question is, when I set the soldiers, do I set them on clay and sand mix paste, or can I set them with refractory mortar. (?)....

Imo mortar is optional if the the dome brick (soldiers in your case) need further leveling due to an unlevel hearth. Otherwise it is not necessasry. They can be set dry with only mortar between the vertical joints. It's your call.

I’m using perlite and concrete for insulation And it’s 4 1/2 inches thick Under Under the oven floor.....

With your second post, I still don't see an actual clarification on wether or not the dome brick (soldiers in your case) will be sitting on insulation?

[david s]

The dome bricks can also sit on top of the floor bricks in which case you can mortar or not, your choice. The advantage of this over sitting the dome bricks on the insulation is that the perimeter cuts of the floor bricks can be pretty rough. The disadvantage is that replacement of a floor brick at the perimeter (extremely rare) is way more difficult.