Find your refractories

How to choose refractories

Start with what you’re building and how hot it gets. The finder above matches brick, mortar, castable and insulation to your project and the temperature rating you need.

1. Hard or soft brick? Hard (dense) firebrick takes heat and wear: use it for wood and gas kiln fireboxes and bag walls, forge floors and bread and pizza ovens. Soft insulating firebrick (IFB) is light and holds the heat in: use it for gas and electric kilns, gas forges and heat-treating ovens, and as the insulating layer behind dense brick.
2. Choose the temperature rating. A soft brick’s number is its rating: G-23 is rated to 2,300°F, G-26 to 2,600°F and G-28 to 2,800°F. Choose a rating comfortably above your hottest firing. Cone 6 is about 2,230°F and cone 10 about 2,350°F.
3. Mortar to match. Lay brick with a very thin coat of air-setting mortar such as Derby 3000HT or Blakbond. Blakbond is made for insulating firebrick; wet soft bricks before you mortar them.
4. Cast what you can’t buy. Loucast 3000 casts dense shapes, such as forge and oven floors. Litewate 23 casts light, insulating shapes.
5. Add insulation. Superwool HT blanket and Kaowool HT board line and back up kilns, ovens, forges and furnaces.

Most kilns, ovens and forges use a combination of these. Discounts are available on pallet quantities of firebrick: contact us for a quote or for help planning your project.

Common questions

What does delivered price mean?

Delivered listings include shipping in the price. Their prices are for the Northeast, and a few add a small zone charge elsewhere. Other listings add shipping at checkout, and bricks sent by UPS carry a small per-brick packing fee.

What are arches, wedges, splits and soaps?

Straights are standard 9 by 4.5 in bricks. Arches and wedges taper, for arched roofs and round walls. Splits are half as thick as a straight, and soaps half as wide.

Can I use soft brick in a wood or salt kiln?

Yes, as the insulating layer behind dense brick. For the hot face of salt and soda kilns, ask us about high-alumina hard brick.