Cooking Floor and First Course

[JoeT62]

I know that the plans state that the oven is more efficient if the first course sits outside the cooking floor:

"The advantages of the round floor are that it has fewer seams,
and the oven dome itself sits directly on the hearth, not the
cooking floor, which is more efficient."

Maybe this has been covered, but I'm not certain why this should be so. Also, does anyone have a handle on what kind of efficiency boost this gives? I plan on a herringbone firebrick floor, and if the boost is substantial, I will certainly go to the trouble of cutting the perimeter bricks into a round pattern, but if it isn't an appreciable difference, I'll skip it.

Thanks!

[james]

That's a tough one. I can't put a figure on it. I think it is fair to say that most Pompeii ovens are built on top of the cooking floor, rather than around it -- thought in some way I think that is a reflection of the fact that it is easier to do.

Any other takers on this?
James

[Archena]

Maybe because it's conducting heat straight to the insulation rather than into the brick?