SuperIsol installation details

[james]

Hello all,
Here is a sticky posting on using Super Isol. It is from the Super Isol supplier. I don't think there is anything new or surprising here, but the information is valuable. This note might be ammended with additional information from the technical folks at the producer.

James

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Super Isol is a very porous product and will suck the moisture out of your mortar. Try slightly dampening the board first, so that the moisture is not as easily absorbed by the board.

The Super Isol should stick to bottom of an existing hearth using skamolex glue. Again, try slightly dampening the board.

If super isol is slightly dampened, it will retain its properties upon dry out. It should not be immersed or soaked in water. Also, it should be dry before being exposed to heat. If the board has to much water and sees high temperature, steam will be created. This steam will have to escape - possibly causing cracks. If to much steam is created, the refractory may "pop". This is true of all refractories, not just the super isol.

[Marc Olson]

Re: SuperIsol installation details

I'm in the process of designing my hearth and curious if you use the SuperIsol how you 'fill in' the extra space to the sides of the hearth if you place the superIsol directly on the first layer of concrete.

Seems like another approach would be to put the SuperIsol on top of the first layer of concrete and then pour the balance around it to 'seal' superisol under the oven. This would be similar to the approached used to add firebrick to the hearth under the oven to increase the thermal mass.

I guess the alternative would be to use the SuperIsol directly on the concrete hearth and then stucco in the sides of the oven to seal the SuperIsol. That would raise the oven floor 4" off the concrete hearth, so an alternative landing would need to be created.

[james]

Re: SuperIsol installation details

Hi Marc,

I would recomnmend that you fill in any area between the SuperIsol layer and the upper enclosure with either loose vermiculite, or pieces of Insulfrax. In general, you are trying to fully envelope your oven with insulation above, below and on the sides.

If you place the SuperIsol on your concrete layer, and refractory mortar the oven floor to that and set your dome around the floor and seal that down with refractory mortar, the oven itself is assembled and done. From then on, everything else should be insulation.

Helpful?
James

[Marc Olson]

Re: SuperIsol installation details

What about the extra space that this creates between the oven floor and the surface of the hearth? Seems like a better approach would be to embed a circle of SuperIsol in the top layer of the hearth concrete so that the oven floor is closer to the hearth surface so that the landing doesn't end up needing to be 4" thick.

[james]

Re: SuperIsol installation details

Hi Marc,

I see your point in wanting to have the oven landing that you build line up with the top of the cooking floor and vent landing. One option would be to fill your landing area that butts up to the oven floor/vent landing with enough concrete to reach the level you want. You could also build it up with concrete board/hardibacker. Some of this depends on how thick your oven landing material is. You are definitely right in that you want the landing and oven floor to be at the same level.

It is structurally sound having the oven floor and dome resting on the SuperIsol. There are three layers: the structural concrete, the SuperIsol board, and the oven. They just sort of sit there, and there is not a structural need to put anything around the insulating board.

James

[bolex16mm]

Re: SuperIsol installation details

I am new to this forum and this is my first post. I have started construction on the Pompeii oven and my next step is to lay the hearth. I am considering using SuperIsol for the insulation. I have a couple of questions. One is that if I use SuperIsol is it correct that all I need to do is pour a 3 1/2 concrete slab and put the SuperIsol boards on top of that? Second, since I am only working on the oven part time and it will take me a while to finish will rain and dampness ruin the SuperIsol boards. I live in Pittsburgh and it does get wet in the fall.
Tony

[jwnorris]

Re: SuperIsol installation details

Yes, you can place your SuperIsol board directly on your concrete slab. As for weather, I would cover the board with plastic sheeting to keep it dry. It does suck up moisture and what ever moisture it gets will have to be driven out during your curing fires.

J W