5/8" metal deck?

[aaron4osu]

I building a wood oven using the basic directions? I'm cutting a few corner and making use of some materials i already owned. So after pouring the foundation i then following the cinder block design for the stand, i have topped the stand w/ 5/8" steel instead of pouring a foundation on top of the stand. This is the stuff that's used on roadways. Anyway, my question is can I go lay my firebricks right on top of the metal? I planned on using the sand, firebrick, water mixture directly on top of the metal. or i could lay down a few inches of gravel first. what do u guys think? My friend has a mold to pour my own oven that will sit on top of the firebricks. thanks, aaron

[RCLake]

Remember to have insulation under the firebrick floor, either vermiculite or an insulation board such as the FB board. Otherwise the heat will escape down thru the floor and I imagine that steel plate would get awful hot.

[Les]

Aaron,

The fire brick needs to be on top of insulation. I believe the plans call for around 3 inches of a vermiculite mix. Some of us have opted to set them on insulation board. Either way you go, you need to have them insulated or you will lose your floor heat.

Les...

[dmun]

Insulate! Insulate! Insulate!

Gravel, sand, ground glass: none of these things insulate worth squat.

I can just see that six hundred degree piece of steel putting a brown stripe on the front of your jeans as wrestle your firewood around in the oven.

[james]

Originally Posted by dmun

...
I can just see that six hundred degree piece of steel putting a brown stripe on the front of your jeans as wrestle your firewood around in the oven.

Now there's a good mental picture. :-)
James

[RCLake]

This is the second time today I've thought of Rocky Mountain Oysters in a WFO, earlier George was describing how to get/crawl out of the vent and protecting valuable items. Didn't mean to turn this discussion in a strange way, but lots of insulation between that steel and floor.

[aaron4osu]

wow, thanks 4 all the help. do u think i can use that 2" thick blue iso-board from lowes or Home Depot? I think it's like $30 per 4'x8'x2" Would i still go over that w/ sand vermiculite mix? I'm planning on using an insolation blanket over the oven. I have not decided if i will enclose it or not yet. I just found this site and can't believe how big the community is. So many great ideas to think through. Great Job Everyone!!

[Les]

Aaron,

I don't think so - I believe the board you are referring to is a foam product. You need something that can withstand the extreme heat you are going to generate. Forno bravo sells what you need or you can do a google on insblok 19 (and there are other products) - we prefer you buy it from James If you refer to the plans on this site, it will give you a recommendation of a sand / clay mix for leveling the floor. Good luck and keep the questions coming - we're here to help another brother of the brick.

Les...

[RTflorida]

I think Les is spot on, that blue foam board is not rated for high temps, it is a wall/attic insulation; at the very least it will melt.....maybe worse

RT

[dmun]

The foam board might also outgas nasty fumes when it gets hot. If cost is the primary consideration, shop around for big bags of vermiculite or perlite, garden centers, pool suppliers and the like. It mixes with a little portland cement to form an effective insulator, 4" of perlcrete are almost as good as 2" of cal-sil.