Heatloss through landing and vent if using Fire brick?

[jcg31]

I note that many of the ovens being built are using firebrick to complete their entry way (landing, arch, vent). I read elsewhere in the forum that it is best to construct the cover arch and landing for the entry way out of a less conductive material, so there isn't unneccessary heat loss through these bricks. Is using firebrick a problem with this portion of the build? and if so what is the preferred material ?

thanks,
Jim

[Unofornaio]

I read elsewhere in the forum that it is best to construct the cover arch and landing for the entry way out of a less conductive material, so there isn't unneccessary heat loss through these bricks.

>What is this material you read about here that is less conductive?

This area is already susceptible to accelerated heat loss because it is an external component of the chamber so to speak and of course there are the 2 openings...

I think what you are asking is if one or another material will "wick" heat from the oven chamber at different rates. My answer is No. This is just a cool spot for the over there is not much you can do about it.

Remember when you are not cooking the placement of the door seals the oven chamber and the heat cycles back through this area you ask about. In addition since heat rises this area is ususlly being washed over with the hot air escaping from the oven. This areas heat loss impact in the over all scheme of things is insignificant.

Is using firebrick a problem with this portion of the build? and if so what is the preferred material ?

> No its not. Some cast the vent out of refectory concrete others use fire brick.

[Hendo]

Jim,

Not quite sure what you're after here, but for aesthetic rather than practical reasons, my vent walls and arch will be constructed from clay bricks to match the rest of the kitchen décor. The firebrick floor however will continue into the vent until the ash slot (about 4"), after which there'll be a granite floor & landing.

To isolate the two different brick materials, I'm going to have a half inch gap with insulation of some sort stuffed in it. So looking down over the vent there will be the firebrick oven opening, a ½" gap, then U-shaped clay brick walls for the sides and front face of the vent.

At some point just above the firebrick oven opening, I'll have to put in a lintel bar to support clay bricks at the rear (with another insulated gap) so I can continue the chimney up and through the roof. It will have a metal flue of some sort inside. I'll work it out when I get there, but my intention is to completely isolate the firebrick from the clay brick.

Hope this helps,
Paul.