Foundation set time

[egan5134]

Hey Guys,

So were starting our foundation today and really want to get a move on with the oven. Did anyone follow the 1-2 day setting time prescribed by the FB instructions? We just want to get the block stand built ASAP and get the oven in order. Any ideas on adequate time and such? Thanks!

[Ken524]

I would definitely give your concrete foundation at least a couple of days. Keep it moist and covered with plastic.

Take your time, have fun and avoid the shortcuts and your oven will cook amazing food for decades

[egan5134]

Thanks a lot Ken. Foundation is set, and we have the block stand put in as well. Were going to wait a few more days and pour the hearth slab. A quesiton for you though, if you happened to use the vermiculite/cement mix, what is the cure time for that, or point that it can hold weight of the dome? Or do you happen to have any experience with the double layer of firebricks on top of the hearth for extra mass/insulation.

[Ken524]

Hi Egan,

I sent you some of this info via our private discussion...

After you pour the 4" vermiculite insulating layer on top of your hearth slab, let it cure for about a week. Keep it covered and slightly moist. Once cured it will be like crumbly styrofoam (it's really weird stuff).

Firebricks are thermal mass. They are NOT insulation. Don't confuse the two. You really don't need an extra layer of firebrick in your floor. It will take a lot longer to get your floor up to temperature, require more firewood and it's just not necessary unless you are into serious commercial bread baking (dozens of loaves/day).

As I said in our private exchange, please don't take a shortcut on the insulation. You must have 4" of vermiculite/cement or 2" of refractory insulation board directly under your floor.

Sadly, we often have builders show up here asking why their floors never get hot. Guess what? They didn't put insulation under their floors

Have fun with your build and be sure to post some pics for us!

[jrabeau]

Hi,
Regarding the comment about adding an extra layer of fire bricks to the floor, I am considering doing this to increase the heat time of my oven. I actually have a clay oven, which I'm also thinking of how to add layers to the wall from the inside (the oven is already built and much in use). Perhaps adding another floor layer would suffice?
Thanks,
Jim

[jrabeau]

Hello,
I have a clay dome oven, which is fully insulated and seems to hold heat very well, but I am now wanting to extend my baking time. Does any one know about the effectiveness of adding another layer of brick to my oven floor? Also, what about adding more clay to the inside surface of the dome? Seems difficult, but conceivable.
Any experience and feedback would be greatly appreciated.
Cheers,
Jim