firebrick conundrum. Help needed, not offered. Pompeii Oven Construction Discuss firebrick conundrum. Help needed, not offered. in the Pizza Oven Design and Installation forums; I have read a lot here about the various firebrick i.e. heavy, medium & light duty. I have read about ...

[KEmerson]

I have read a lot here about the various firebrick i.e. heavy, medium & light duty. I have read about alumina and silica %s. I have read about weight of brick, size, heat retention, thermal cycles etc. But when I go to the assorted block & stone vendors locally no one seems to have a clue. "We sell firebrick. Period." is not far from the common response to my inquiries. I am apparently more informed and better educated than the people who sell the bricks, which essentially means they can't help me.
Yesterday I looked at some firebrick. They are 8.75"x4.25"x2.25", are yellow (not red) and weigh 6 lbs. That's all I learned. And unless I ask other brick sellers to weigh their brick, this is all I'm likely to learn from them too.
So, do any of the more experienced oven crafters here have a clue? Is this 6 pounder just too full of alumina and not enough silica? Is it insulation brick? Is there a range of weight regarding a brick's "heavy, medium or light" duty? I understand (or think I do) that a brick around 8 pounds is what I'm looking for. Is this two pound difference an indication that these are the wrong bricks? (I don't have my notes right in front of me but I think I recall that they are going for about $1.39/ea.)
Thanks.
Kim

[Gromit]

Masonry suppliers only have "firebrick period" and it will be low duty. Refractory suppliers will have medium and high duty brick for 3 to 4$. Your brick is about 20% smaller than the 9 x 4.5 x 2.5 @ 9lb typical brick. Buy one and give it a more accurate weighing at home to see if the density is close to standard.

[RTflorida]

Kim, the bricks mentioned seem very similar to what I used (roughly the same dimensions). Mine weigh 6 1/2 lbs. They are light duty, used for fireplaces (as I was told), and are perfect for our ovens. Other than adjusting my plans for the size difference, I could not be happier. Mine were less than half the cost of the 9 x 4.5 x 2.5 bricks - only 77 cents each.

RT

[bernerdog]

Others suggested asking the supplier for the MDS (Material Data Sheet?) which shows the % silica and alumina. I did and found just what the other builders recommended tho` costing more than in other areas at about $1.60 @ in red or buff with the latter having a higher temp rating but both the same size as often mentioned here (2000 degrees v. 1700).

[KEmerson]

I just went out & bought a brick each from two different places. #1 is 9"x4.5"x2.5", weighs 8# and costs $1.10. #2 is 8.5"x4.25"x2.5", weighs 6# and costs $1.50. No one had an MDS though they knew what one is.
It looks like #1 is the way to go.
Thanks for the input.
Kim

[dmun]

I'd vote for #1. More brick for less money, what's to argue? Brickyards are unlikely to have material data sheets. I'd guess they are ordinary low duty firebricks, from two different manufacturers.

[texassourdough]

Hi Kim!

I would vote for #1 also based on the info. You might ask them if they can tell you the manufacturer and go online to get the MDS. There is a good chance it MIGHT be available. But I wouldn't sweat it. More brick, more mass, more heat retention, less money.... Hmmm. I think the answer is pretty clear!
Jay

[KEmerson]

#1 it is. And to think it's only two miles from home!
Thanks all.
Mangiamo!

[Dutchoven]

Kim,
#1 is my vote too...don't ask them about refractory mortar either though...they will look at you like you have a third ey in most cases...unless they happen to be a Heatstop dealer.
Good luck!
Dutch
Oh. I grew up in Orange county...not far off from where you are...near middletown

[wesslock]

I bought heatstop from Kingston Block , I think it was called which is only a couple of minutes away. I too think I got the wrong fire brick - altho my oven works I dont think it holds heat as well as it should. Seems to me the floor gets cooler after I cook for a while but there may be other issues.

I got my firebrick from G&H in Greenville and they werent too helpful either.