Firebricks – heavy dense fire clay bricks
Now days they are called heavy and dense Firebricks but old masters still call them fire clay bricks just because they are made of simple fireclay (which actually is the most ordinary mud.) Fire clay can be easily located out in the nature but it must containing the right refractory properties, suitable content ratio of silica and alumina. Some shops call these bricks fireplace bricks. They are used for instance for building cooking chamber in wood fired ovens, for creating fireplaces, all sorts of fire boxes and wood heaters’ lining, linings in a small or the hugest industrial furnaces, you name it. 
Fire clay bricks are very heavy/dense having low porosity and even on reheatings they can last for very/very long time.
Some may confuse them with insulating lightweight firebricks, those are used in different applications. Dense firebricks can be cut only with diamond wheel attached to high speed handheld angle grinders, on an ordinary building brick saw or sliding drop saw for cutting bricks. Fire bricks can be chopped in half easily by using brick chisel and a couple of hits with a heavier hammer. It is fun and quick but may you want to achieve precise nice cuts hire a trade machine or buy yourself at least small size grinder. Before cutting soak the brick in water by dipping it in a bucket of water or in a wheelbarrow if you had too many. Leave the bricks in that water for 5 minutes minimum. 
The cutting diamond wheel will last you for a long time if the firebricks are cut wet plus you won’t breath in any dust, and of course cutting gets a lot easier and faster!
What firebricks type to use?
When it comes to firebricks and dense refractory products composition content often Alumina (AL) ingredient is looked at which ranges ordinarily between 18% to 40% of alumina in modern product’s body. The percentage range is important for choosing the right product for the right temperature or Orton Cone but mainly if a high temps are applied. 
Alumina influences bulk density a lot and therefore also porosity, or if you like the weight of fire bricks. No need to apply above 26% in wood fired oven temperatures range but you can in case a low grade isn’t available to buy. Absolutely safely 18% AL amount firebricks can be used in wood ovens (you can melt and cast color metals in it too.) Furnace’s chamber build out of 18% will perform and last the same way as 30% alumina product.
Apart higher co$t, additionally, higher Alumina content grades make these bricks harder and brittle (more glossy if you like) making them absorb less steam e.g. from under pizza dough bases being cooked or bread dough. However one can get used to cooking in such oven fast.
Even though you can hear other words from a few suppliers who sell not locally manufactured product, conductivity and heat absorbing capacity is not influenced much at all by higher or lower alumina content. Higher grades won’t create magic temperature difference in cooking environment and vise versa. Main reasons for this are modern imports, one high alumina range suits all business and applications, less varieties to stock, higher markup and margin, those are the reasons if 18% to 26% brick isn’t sold by a store. Look for locally manufactured product, lower grades cost less to produce and they sell them for less. Where I buy refractory 26% AL firebricks costs $1.98 per one brick.
BTW mineral Graphite is lighter in weight by half if compared with Alumina or refractory bricks, and Graphite absorbs much more heat than firebricks (more reading about firebricks’ thermal conductivity and alternative for firebricks replacement.)
- 21% Alumina firebrick : 1850 tons Bulk density per Kg/m³ : Thermal Conductivity : 0.98 W/m.°K : 23-Orton 1620°C
- 24% Alumina firebrick : 1.925 tons Bulk density per Kg/m³ : Thermal Conductivity : 1.02 W/m.°K : 27-Orton 1640°C
- 27% Alumina firebrick : 2 tons Bulk density per Kg/m³ : Thermal Conductivity : 1.05 W/m.°K : 30-Orton 1670°C
- 33% Alumina firebrick : 2.15 tons Bulk density per Kg/m³ : Thermal Conductivity : 1.07 W/m.°K : 31 ½ -Orton 1700°C
- 38% Alumina firebrick : 2.2 tons Bulk density per Kg/m³ : Thermal Conductivity : 1.13 W/m.°K : 32 ½ -Orton 1720°C
- 40% Alumina firebrick : 2.25 tons Bulk density per Kg/m³ : Thermal Conductivity : 1.13 W/m.°K : 32 ½ -Orton 1720°C
TYPICAL TECHNICAL DATA – DENSE FIRE BRICKS
Physical Properties of Firebricks (23% alumina product)
- Bulk Density : 1915 Kg/m³
- Modulus of Rupture : 5 MPa
- Permanent Linear Change on reheating 5 hrs. @ 1400°C : -0.35%
- Cold Compressive Strength : 15 MPa
- Thermal Conductivity @ 750°C : 1.01 W/m.°K
- Apparent Porosity : 28%
Chemical Composition of Dense Firebrick – 23% Al grade
- Alumina : 23%
- Silica : 73%
- Ferric Oxide : 1.4%
- Accessory Oxides : 1.1%
- Titania : 1%
- Frits
Who is your firebrick or refractory supplier, do you have contact-s on them? And where are you located? Please leave your comments for others below…
May 28th
My refractory supplier is ClayPave Pty. Ltd. located in Dinmore, Brisbane, Qld., on the way to Ipswich. They have distributors all around the country and Internationally.
It is large Australian manufacturer of refractory and clay products. ClayPave produces all grades of firebricks. Heat resistant mortars, ready mixed air-set in bucket, or fire clay in bags to mix your own refractory mortar at home – one bag is plenty for building 2 ovens. Best prices, delivered if needed.
Standard firebricks or splits: AUD$2 to $2.20 each
Fireclay: $25 per bag (large bag enough for 3 ovens)
Pre-mixed heat resistand mortar: $33 per bucket (1 needed)
Packed on the top of the palette with firebricks.
More info is here in the post about buying firebricks.
Web: claypave.com – look for their refractory resales in your area they are listed there, also overseas.
Phone: (07) 3282 1444
Email: claypave[at]claypave[dot]com
Address:
Factory & Sales Centre
Chum Street
Dinmore, Qld. 4303
June 1st
Firebricks and refractory mortar in Perth, Western Australia:
Ian Mears, phone: 08 9434 9202 / mob: 0414 885 337
Address:
Mears Refractory Services pty. ltd.
Unit 3
9 Corokia Way
Bibra Lake
Perth, W.A. 6163
Western Australia
Ian is a nice bloke quite knowledgeable about ovens, very helpful, won’t mind to open the warehouse at odd hours when someone really needs when ran out of fire bricks. He hires brick saw -standing idle.
June 30th
Where is the closest place I can get refractory cement from as I live in York Western Australia.
July 1st
Did you check under ‘Refractories’ suppliers in phone book, or ‘Heat Resistant’ material?
I will ask Mark if he doesn’t know a place there around you. Have you located firebricks?
July 23rd
Im still looking for a refractory supplier close to me in York.
If you find a supplier could you let me know as soon as possible.
July 24th
Hi Colin, Firebricks in WA are a hard thing to source but I do know of a place that does supply them, The Potters Market 56 Stockdale Rd O’Connor,Tel No 93376888.I cant tell you how much they charge per brick but I do know in comparrison to prices paid in other states from refractory suppliers direct they are a bit more expensive.When I built my oven 3 years ago I used normal solid bricks ” Austral Collie ” which is a cream solid .My oven is as good today as when I built it, Hope that helps Mark
July 24th
PS They also can supply your fireclay needs
July 24th
Hi Colin,
Yes the clay bricks Mark mentioned that he used for building his oven in Western Australia are almost identical to clay firebricks from Ipswich, they contain grog in the body as well. You can use them. Then there are solid clay bricks from Midlands somewhere, they are the same, can get the contact details if you needed. Maybe far from York?
July 24th
Rado,
I hav ealready sourced some fire bricks,but Im more interested in getting some refractory cement for the fire bricks.
July 25th
WILL TRY Ian Mears in Bibra Lake
Thanks for all the info.
August 7th
supplies in USA ; if you live in or near Maryland, you can get Mt. Savage “Medium Duty” fireclay bricks (43.1% alumina content) at Potomac Valley Brick and Supply Company. They come in yellow or red. I got mine at the Rockville, MD location (3 Derwood Circle), for $1.33/brick. They also sell the fireclay mortar in pre-mixed tubs. The bricks I bought there differ in dimensions (height) from the Australian ones (2.5 inches vs. 3 inches).
Thanks to Rado for all the help!!!
Charlie
August 10th
I have looked locally in Western Australia – Perth:
Potter’s Market at $3.95 per brick;
Ian Mears at $3.88 per brick (smaller than normal 230x115x60);
Veolia Refractories $7.80 per brick;
Eastern States (prices including shipping cost to WA):
Darley Refractories at $6.57 per brick;
Claypave works at $4.77 per brick;
Shipping makes it very expensive to get firebricks to Perth unless you order larger quantity of course.
I have found someone who has a small quantity of leftover firebricks with 45% alumina content and is selling it for $0.50 per brick. I am a bit worried about the higher alumina content and its higher heat conductivity causing bread to burn at the bottom.
Fondu cement ($40) is much more expensive than Portland cement ($6), but as you say, if I want to use it -it is just a small slab. I believe I will need about 4 bags of cement.
August 10th
Today I bought 7 bags of Vermiculite from “The Perlite & Vermiculite Factory” at address “Lot 802 Cutler Rd, Jandakot 6164, Western Australia” phone number 08 9417 8377. The price was $15 cash per 100L bag. This was very cheap compared to some Perth hydroponics shops who sell vermiculite in the 100L bag for $40.
Best regards
September 8th
Suppliers in England. I live 22 miles from London.
Vermiculite from Travis Perkins very large bags £9.40
It is cheaper to go in a van on a cheap return ticket to France to buy the firebricks:
Firebricks in France – from Leroy Merlin near Calais only Euro 1.21 each
Firebricks from Ridgeons U.K. £2.47 + 17.5% vat
Building sand very large bag from Ridgeons £46.73 + vat
Ballast very large bag from Ridgeons £36.76 + vat
25Kg cement from Ridgeons £ 3.49 + vat
Fireclay 25Kg from Buildbase London £21.39
Lime 25KG from Ridgeons £ 7.86 + vat
If not used re-used or second-hand:
Marine plywood for boxing very large piece £ 14.00 locally
Small bricks from £0.30
Hollow concrete blocks from Ridgeons £1.88 + vat
My internal temperature reaches +500°C (932°F) and the outside walls and roof are +20°C (68°F) !
I hope this will help.
Regards
David
September 21st
Tasmania – Firebricks and Vermiculite supply.
firebricks with 28% Alumina content
vermiculite (called shiralite) insulation
from:
East Tamar Maintenance Services Pty Ltd
Temco Road
BELL BAY
TAS. 7253
Australia
ph: 03 63822400
ph: 0418 139041
fax: 03 63822408
They also stock other refractories or refractory materials.
October 2nd
Thanks for the great information Charlie. I live in Maryland and was looking into getting a brick oven. I will have to check out Potomac Valley Brick.
pays to live green’s last blog post: Save and Go Green on Gas
January 14th
Dear Sir ,
I am glad to introduce ourselves as an supplier of various of common refractory material from China.
We specialize in Alumina materials and products, Mganesia materials and products, such as Clay Brick, Bauxite Brick, Fused corundum brick, High Aluminum Block, Nozzle etc. shaped products and Calcined Clay, Bauxite materials, Gunning materials, Ramming mix, Refractory castable and mortar etd. Unshaped materials, which have enjoyed great popularity in the world market.
You can refer to our website http://www.fujingcn.com for further information.
Should you find intrest in our items , please kindly let us know. We shall be pleased to give you our lowest quotations upon receipt of your detailed requirements.In our trades with merchants of various countries, we always adhere to the principle of equality and mutual benefit.
It is our hope to promote , by joint efforts , both trade and friendship to mutual advantage.
Yours sincerely
Mary
Qingdao Haotai Trade CO.,LTD
NO 10 Shandong Road
Qingdao China
Email ID : haotaibiz@gmail.com
MSN ID : mary-mlh@hotmail.com
PHONE : 86532-85029505
13012482827
April 19th
My Firebrick supplier is Vesuvius SA (professional (huge scale) refractory selling directly to the public, too), located off Porcelain Road in Clayville (Olifantsfontein), Midrand, Gauteng. A huge variety of shapes and sizes can be bought from them, as well as various grades and purpose oriented refractory mortar, etc.
I am located in South Africa.
More details on Vesuvius can be found on the Internet (http://www.vesuvius.com), including telephone numbers, etc. Vesuvius is an international company with branches in other countries too.
Enjoy.
Abrie
April 23rd
Very informative post with a lot of historical and present use and name of the bricks. I think this have the ability to convey its meanings and attract the readers attention to this product.
June 11th
Dear Sir:
we can supply Fireclay brick at more lower price that you need urgently ( FOB AUD$0.4-1.2 )
We are professional supplier for refractory brick & ceramic fiber product at competitive price, located in Zibo City, Shandong Province, China. For more information, please check our website ( http://www.zbxdnc.com , http://www.zbxd.en.alibaba.com ), and select the products that you’re interested in.
We have great interest in developing business with you, should you have any inquiries or comments, we would be glad to talk in details through MSN: zbxd011@hotmail.com or any way you like.
June 24th
Either way they’re pretty expensive. I can’t afford to buy the ammount of clay bricks I need.
July 24th
Thanks for the usefull info guys. How many firebricks would one need for a “standard” wood fired stove?
August 14th
Home depot has fire bricks for $1.15, I haven’t found the content info yet
October 28th
If you are importing or plans to import fire bricks or high alumina bricks upto 70-80% contact us. We are India based manufacturing company, established 1978 indulge in manufacturing all kinds of fire and acid proof bricks along with allied material. ranchirefractories.com
December 1st
Brikmakers located in South Guildford, Western Australia, make solid clay bricks and their Geologist advises that their Standard Face Cream Smooths are ideal for pizza ovens with their composition being about 25% Alumina and 68% Silica. At only $195 for a pack of 264 bricks, that works out to about 73 cents a brick (pick up).
December 6th
Dear Sir
we have Enq for insulation Brick and castable for gas filter & Economizer
we will send the Enq if you interset with best regards
Asaad alrawi
December 9th
Folks in and around Central & Western Arkansas (USA) can find good quality firedbrick (9″x4″x2.5″- really 2 & 1/8″) at ACME BRICK Company at Malvern, AR. ($1.40/each as of FALL2009). also good source for fireclay mix (100# sack), “everset” mortar (high temp mortar mix for hearth construction w/ firebrick).
If looking for vermiculite for insulation. can buy large quantity at reasonable price from MIDSOUTH CONTROL & SUPPLY of Fort Smith, AR (really Van Buren, AR).
can follow along our oven construction at:
http://www.flickr.com/photos/pms_swim/sets/72157622409914984/
regards, P. Shepard
January 3rd
Dear Friends:
We are an ISO certified manufacturer of fireclay bricks in China’s fireclay brick base Zibo City.
Our quality and price is way more competitive. If you are interested to buy from China directly, please email me at refractory_china@yahoo.com or MSN ID:jedgxsh@hotmail.com.
January 20th
i do blacksmithing and im looking for fire brick to line my forge with can you sugest where i can get the fire brirk for that high of a heat
March 21st
I live at Sauble Beach on the Bruce Peninsula, 220kms NW of Toronto, Ontario. I can purchase refractory bricks from Shouldice Designer Stone for about $2.10 / 2-1/2 inch brick (in Metric equals to 64mm thick firebrick). They also supply the cement, thru my local building supply dealer, Miller Home Building Centre in Sauble. I should be starting building my oven approximately April 15, depending on delivery. Doug
April 11th
Anyone know where t buy cheap firebricks in sydney??
Please let me know,
giyongkim83@gmail.com
April 14th
I just got the specs on the firebricks sold where I live in Canada and which are imported from the US.
Thermal Conductivity (K-Factor)
Btu/in
At a mean temperature of ft2hr°F W/m°C
400°F (205°C) 8.2 1.18
800°F (425°C) 8.5 1.23
1200°F (650°C) 9.0 1.30
1600°F (870°C) 9.2 1.33
2000°F (1095°C) 9.5 1.37
2400°F (1315°C) 9.8 1.41
TYPICAL CHEMICAL ANALYSIS, Wt. % (calcined basis)
Silica (SiO2)…………………………………………………………… 56.02
Aluminum Oxide (Al2O3) …………………………………………. 37.50
Iron Oxide (Fe2O3) …………………………………………………… 2.09
Titanium Dioxide (TiO2) ……………………………………………. 1.99
Potassium Oxide (K20) …………………………………………….. 1.47
Magnesium Oxide (MgO) ………………………………………… 0.36
Calcium Oxide (CaO) ………………………………………………. 0.30
Sodium Oxide (Na2O) ……………………………………………. 0.074
Zirconium Dioxide (ZrO2) ………………………………………… 0.068
Chromium(III) Oxide (Cr2O3) ……………………………………. 0.039
Phosphorous Pentoxide (P2O5) ………………………………… 0.036
Manganese Oxide (MnO) ……………………………………….. 0.007
NiO …………………………………………………………………….. 0.012
Total ………………………………………………………………….. 99.97
Loss on Ignition, 1000°C …………………………………………… 0.13
We certify that SMITHFIELD (Unbranded) Dry Press Firebrick
manufactured at our Alsey, Illinois plant conforms to ASTM
Specification C-27 – Class 4.1.4 and 4.1.5 for Medium Duty
and Low Duty respectively and C-1261-98 (which includes C-
24 and C-67), as well as, C-16, C-20, C-24, C-38, C-113, C-133.
They are called ‘Medium Duty Firebricks’ however it seems the aluminum content at 37.50 is at the high end and not ideal because not steam absorbent, when compared for instance with firebricks around 23% AL mark, and therefore does this make it very hot or dry ovens which can’t absorb steam (?).
But could anyone here with experience please give me an idea as to whether these are good or not, and if not ideal, does anyone have a good supplier in Canada. They are charging $4.00 a firebrick here inc. tax, which includes shipping from the States (with bulk freight accounts of course), but maybe it is worth my while to find a more ideal product and ship it in.
April 14th
Hi Ash,
Have you noticed the comment above regarding buying firebricks in Canada? Maybe it helps.
Could you ask in the place for the alumina content and also Technical / Physical Specifications of the Low Duty firebrick type that they stock or manufacture? Plus the price?! Can you please let us know those and also the contacts for this company? Low Duty type is what I use and also those they have on offer can be great for this purpose and the temperature range.
You can use the mentioned 37.5% alumina. Even though they withstand continuous use in a lot higher temperature ranges that could never be reached in wood fired ovens and they also cost a bit more, you can use them. They will perform just as well. Regarding the steam absorbing – the same applies to refractory clay tiles or oven floors made out of larger clay blocks (I am not talking about ovens whose have the hotface cast from a heat resistant concrete mixes because I don’t work with them myself in building ovens); basically because the fire bricks with high AL content are denser (glossier/heavier), they have lower porosity so the effect is they absorb moisture ( steam ) slower when compared with firebricks with higher porosity which is common for lower alumina firebrick grades. This effect is minimal. If you work with ovens that have been built from both clay types, low and high alumina content in the brick’s clay body, you will notice only a slight difference when cooking or baking. But this difference can be gotten used to with practice perfectly. With the higher AL grade clay, if you make pizzas in high temps atmosphere, when you place the fresh dough (pizza base) on the hot firebrick floor in the first few seconds the steam builts fast and literally uplifts the pizza.
And logically this effect is even more minimal with floors made out of firebricks because there are many little join lines between all the bricks therefore also the steam from under the pizza base runs out fast (with oven floor made from tiles or a large smooth blocks the steam under the dough holds just a bit longer. Plus, the fact is that firebricks work also as many nicely moving fragments in the heat expansion and shrinking – in contrary the reality is that larger blocks either in the floor or in walls, and square tiles, are often cracking across and the occurrence is caused by the heat expansion with cooling down shrinkage and these heat differences in flat material.)
April 25th
To: Sydney, AUS builders.
I recently found a source of refractory “tiles”. The gentleman has heaps of them and is selling them for around ~1.50ish. I’ve decided to buy a few and try to use them for the inner firebrick arc and maybe break one up into bits to use as a replacement for the broken terracotta tiles filling.
I’ll speak to the seller and ask him if it’s ok to post up details on this site or if i can pass them on.
June 21st
When i see pages like this one about refractory fire bricks i cannot help but be jealous …. i wish was a bit more tech savy to be able to offer great info like you do about pizza ovens fired by wood with all the info on heat absorbing / resistant material or heat insulations … keep up the good work. Thank you.
August 1st
Anyone know where to buy cheap firebricks in Vermont South Victoria Australia ?
Please let me know here or piro52@hotmail.com