firebrick conundrum. Help needed, not offered.

[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]

Re: firebrick conundrum. Help needed, not offered.

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]

Re: firebrick conundrum. Help needed, not offered.

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]

Re: firebrick conundrum. Help needed, not offered.

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]

Re: firebrick conundrum. Help needed, not offered.

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]

Re: firebrick conundrum. Help needed, not offered.

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]

Re: firebrick conundrum. Help needed, not offered.

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]

Re: firebrick conundrum. Help needed, not offered.

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

[Dutchoven]

Re: firebrick conundrum. Help needed, not offered.

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]

Re: firebrick conundrum. Help needed, not offered.

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.

[Dutchoven]

Re: firebrick conundrum. Help needed, not offered.

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.

It shouldn't have all that much to do with the brick type...it is quite unlikely that you would get the really high duty bricks from your average brickyard...all of our ovens lose heat to cooking foods but if you are well insulated you should be OK if you allow the oven to recover a bit before loading again...for instance with ours during retained heat baking the oven is loaded at a floor temperature of lets say 500F when the loaves are finished 22 to 25 minutes later the floor will have dropped to about 440F...we let the oven rest about 15 minutes then steam it which cools it a bit again but in about another 10 to 15 minutes it will be time for loading again and most of the floor will be back up in the neighborhood of 490 to 500...CanuckJim said it very well when he said that a WFO is something you work with rather than something you cook on or in...definitely more like a member of your staff than it is a piece of equipment
All the best!
Dutch

[KEmerson]

Re: firebrick conundrum. Help needed, not offered.

Kingston Block? That's where I got brick #2 above. Are you local? Can I see your oven? I'm in Saugerties. Brick #1 is from Nelsen in Saugerties.

[pizza_bob]

Re: firebrick conundrum. Help needed, not offered.

I recently purchased firebrick from a masonry supply shop in New Haven, CT. I think I checked all of the masonry supply shops in CT and they all seem to carry low duty firebrick (buff and red). Some offered #1 size and others only offered #2. I ended up going with #1 size (buff) for $1.25 each. One thing all these suppliers and bricks had in common was the manufacturer - Whiteacre Greer. Their website carried the MSDS and I attached it below. I'm not sure if their product is the best quality or the most appropriate for a pizza oven but it was all that I can find in my area. One complaint I have is that the bricks seem to chip so easily! You look at them the wrong way and a corner chips off!

Goo luck with your search and build.

Regards,
Bob

[wesslock]

Re: firebrick conundrum. Help needed, not offered.

My oven is in Durham , on the way to Windham. I am only there on weekends , if we could work it out you could swing by. Maybe could time it for lunch. I still havent finished the outside - have been too busy making pizza and quite tired of moving rocks.

[KEmerson]

Re: firebrick conundrum. Help needed, not offered.

Wesslock: Durham is a stone's throw away (I get met from Heather Ridge in Preston Hollow when they come to the farmer's market here). Yes, I'd love to see the oven especially since it is incomplete. Weekends are fine with me. Email me kim@hearth2hearth.com and maybe we can arrange something. Thank you!!

pizza_bob: Thanks for the MSDS. This shows the alumina/silica ratio to be about what I understand to be what we need - roughly a 30% alumina.

Thanks,
Kim