Vermiculite insulating base questions

[sonomacast]

I am mounting my oven onto a trailer, I am about to cast the concrete slab (2") and then the Vermiculite concrete insulation slab. My question is this, How strong is Vermiculate concrete (Movement etc) And will the concrete be spongy? It has to be firm and strong to take the oven and keep the segmented floor level and in place, Thank you

[david s]

Re: Vermiculite insulating base questions

You can make it stronger by adding more cement, but as the table shows the more you add the less it will insulate. you may need to therefore increase the thickness. Adding sand really boosts the strength, but also really reduces insulation.

Vermiculite Insulating Concrete--The Schundler Company

[david s]

Re: Vermiculite insulating base questions

And the compressive strength is probably about the same too.

[deejayoh]

Re: Vermiculite insulating base questions

Given you are mounting it on a trailer, is it safe to assume you're building a portable oven for a business or something?

If you're using the oven for something like that, you might not care as much about heat retention overnight, so you're more willing to trade off heat loss for rigidity

[sonomacast]

Re: Vermiculite insulating base questions

I laid the vermiculite base today, 3" of Vermiculite concrete sitting on 2" strong concrete. I had trouble getting the Vermiculite at a good level finish, What is best to put between the vermiculite concrete and the oven floor to keep everything level? Thank you

[david s]

Re: Vermiculite insulating base questions

50/50 sand and clay, throw in some lime if you want it stronger.

[hungng]

Re: Vermiculite insulating base questions

50/50 sand and clay, throw in some lime if you want it stronger.

probably a silly question but do you put that on dry or with water?

[david s]

Re: Vermiculite insulating base questions

Some people do it dry and just settle the firebricks in getting them nice and level. I prefer to do it wet. You can also do it wet, get a good level surface, let it dry then place the bricks.