How To Select The Best Insulating Fire Brick For Your Application

All About Insulating Fire Bricks

Insulating firebricks (also known as IFB) are a crucial component of refractory building. These soft bricks provide a lining for high-temperature furnaces and act as backup lining to increase the effectiveness of the refractory when dense brick is the primary lining.

Today, we’ll explore firebrick and how to select the best insulating firebrick for your application. At RSI, as one of the top insulating firebrick suppliers, we work with a wide variety of industries to build kilns and furnaces and supply high-quality refractory bricks and products.

Breaking Down Insulating Fire Bricks

As with most refractory products, insulating fire bricks are made to withstand high temperatures. The refractory bricks are mainly used as insulation and for applications without a lot of mechanical activity. Interestingly, one of the more common uses for insulating fire brick is in crematoriums. They’re also used extensively in heat treat and as a backup in aluminum melting furnaces. But the primary use of IFB is right in the name—insulation.

These lightweight bricks are ideal for thermal insulation in refractory applications with various temperatures over 1000°C due to their low thermal conductivity. Standard temperature ratings are 2300°C and 2600 °C. At RSI, we carry a complete range of firebrick, including IFB in 2800°C and 3000°C ratings. They can stand up to the intense heat of high temperature applications. 

One of the main advantages of IFB is that they’re easy to work with. The special type of brick is lightweight and made from soft materials that you can easily reshape and cut to precise dimensions. If you need custom lining for a kiln, IFB can help you create the shapes that you need.

Of course, the softness means that IFB is also very porous. Insulating fire bricks are subject to erosion, wear, and tear. If you’re handling heavy mechanical equipment, your IFB will break down relatively quickly compared to high-strength dense firebrick.

Choosing a product like our super duty brick is ideal for most industrial applications because it’s quite durable and heat tolerant. Super duty brick has good wear resistance with unsurpassed performance for high insulating value. It’s easy to create custom shapes to replace a refractory fire brick or two if one should fail.

IFB makes ideal kiln furniture and self-supporting structures. Insulating bricks are an excellent choice to act as support in your furnace and other refractory materials. This is an affordable, simple, and easy-to-use brick. Even with the high porosity, IFB will protect your furnace’s other tougher-to-replace and more expensive components.

Choosing the Right IFB

High temperature insulating fire brick is typically comprised of silicate or alumina, along with other raw materials such as clay and kaolin. High alumina bricks and denser IFBs are more temperature-resistant.

IFBs help to keep furnaces running efficiently. The refractory ceramic material holds in the heat while providing a layer of insulation and protection against hot-facing surfaces. With insulation bricks, you’ll get faster heat-ups and less heat loss for better refractory performance.

One of the most impressive aspects of IFB is that it withstands such high heat while still remaining very lightweight. It’s far lighter than a standard firebrick. Thanks to its porous design, firebrick is easy to maneuver and shape to fit your application and needs.

We refer to this light weight aspect as low-density. During the IFB-making process, the combustible materials, like straw and sawdust, create a pore structure that makes the bricks less dense than typical brick. These micropores help the bricks retain and maintain heat.

Soft insulating fire bricks are available in standard brick shapes, as well as other shapes and sizes as needed. Fortunately, the lightweight soft brick is very easy to customize, even with hand tools—using a drill or hacksaw. IFB isn’t sealed and stands up well to cutting and reshaping without crumbling.

At RSI, we carry soft brick in standard sizes of 9″x 4″ x 2.5″ and 9″x 4.5″ x 3. We can also work with you to meet your custom needs as well. If you have an idea or need you’d like to explore, reach out, and we’ll help you find the right IFB for your refractory needs.

How Long Do IFBs Last?

What is the lifespan of soft brick? It all depends on the application. Even though insulating firebrick is softer than other types of refractory brick, it’s still likely to last several years. The longevity of your insulating fire brick depends on the application and factors like chemical exposure.

IFB withstands thermal shock and thermal cycling very well. Despite being soft and easy to cut, the chemical composition is surprisingly temperature-resistant and an excellent insulator.

Insulating firebrick is helpful for repairs as well as new builds. If you have crumbling brick in your furnace or oven, you can cut and customize a replacement brick using IFB. Replacing a few bricks is much easier than rebuilding a kiln or furnace. Because IFBs are easy to shape, you’ll get the replacement you need quickly.

We carry an array of insulating fire bricks, soft bricks, and many supporting materials. We’ll help you choose the best, most durable brick. We’ve found that the best fire brick is often specific to each customer and application. Contact us today, and we’ll help you choose the right IFB solution.