Bought Insulating firebrick in error??? Help!

[Joel's mom]

Hello all! I'm a newbie here and posting my first question,hope you can help me.

It turns out that I bought lightweight or insulating firebrick instead of the standard heavyweight firebrick. The size I picked is 4x9x2.5. Bought it from a brick yard, Man who sold it to me told me it made no difference. Took his word but after reading and researching ( I know should have done that first ) it is not the same. Now can I make my oven pizza out of this brick then cover it with refractory cement, will I get the same results. It will be insulated as well. Oh and my floor is heavyweight firebrick.

Please any and all feedback will be appreciated.

[deejayoh]

Re: Bought Insulating firebrick in error??? Help!

Short answer. No.

The firebrick needs to absorb and throw back heat. IFB won't do either. You can't mortar it too well either.

I think the answer is to take it back and get the right stuff. Tell Mr. "It doesn't matter" that it does. Talk to his boss while you're at it. Tell him you want a discount for the inconvenience!

[Joel's mom]

Re: Bought Insulating firebrick in error??? Help!

Thank you for your reply. I called the place they will exchange but now I am thinking I should keep them and use them for insulation. Thoughts on this?

[deejayoh]

Re: Bought Insulating firebrick in error??? Help!

I'd recommend taking it back and using something else.

It's not great for insulation. It's too difficult to apply. You can wrap with blanket, or put up masonry brick by brick... Which would you choose? Plus I don't know offhand how it compares to the efficacy of CF blanket - but I would bet it's not as good an insulator.

[the_dr_masuess]

Re: Bought Insulating firebrick in error??? Help!

You can use some of them under the cooking floor of the oven but more than that is not necessary. You should definitely take the rest back.

[tonybaker]

Re: Bought Insulating firebrick in error??? Help!

don't be too hasty in returning heavy bricks! My round oven is made from perlite insulating bricks on the dome and a couple of really heavy slabs in the cooking floor. The idea is that the insulating bricks reflect the heat down to the slabs where it soaks in. My oven heats very fast and cooks well. Also the bricks were so easy to cut. Insulation is perlite/cement mix with an overlay of plain mortar for weatherproofing. You can read plenty of posts on here from vault oven builders who complain of the amount of wood needed to get their ovens up to temperature - those heavy bricks are just soaking all the heat! You want to reflect it downwards?

[cobblerdave]

Re: Bought Insulating firebrick in error??? Help!

G'day
Its interesting to hear about your oven but after seeing a few oven now in real life and not only this forum and others, I'm pretty happy with what a Pompeii oven does.
Its a full weekend oven and not a high mass week long oven which suits me fine. A burn of 2 hours gives you pizza for a long as you keep an active flame going. Close it off and bake bread and roasts over the weekend from the heat.
If you don't want to cook to a cooling oven over a weekend don't. A short fire of 45 mins will give you 4 to 5 pizza. 45 mins of fire and pull out the coals let the oven rest and you can bake or roast . 30 mins of fire will give you a great bed of coals throw a Tuscan grill in and BBQ .
I never worry to much about wood I run my oven on sticks really and never buy wood for it . I have run out of wood and a 1/2 hour hunt in bit of local bush will turn up enough for a cook.
I'd never want to discourage any WFO build but I do believe the Pompeii works well and is proven design
Regards dave

[GianniFocaccia]

Re: Bought Insulating firebrick in error??? Help!

Insulating firebricks are light, aren't they?

[winnd89]

Re: Bought Insulating firebrick in error??? Help!

I have access to firebrick containing 63.5% SiO2 and 27.6% Al2O3. I'm not sure if this brick will work for my dome and floor given the fact that it is not the 50%/35% recommended by fornobravo. Should I look elsewhere? Thanks

[the_dr_masuess]

Re: Bought Insulating firebrick in error??? Help!

They would definitely work. If you can get them for a great price then I wouldn't pass them up.