Basic: Heat-Resistant Refractory Concrete Mix

Basic: Heat-Resistant Refractory Concrete Mix

This article has been superseded:  How To Make Refractory Cement

Refractory Concrete is a type of concrete that is designed to withstand higher temperatures, such as those found in kilns, furnaces, and boilers—often called heat-resistant concrete or refractory cement.

Regular concrete doesn't do too well with high temperatures, in fact, high temperatures will dehydrate regular "bog-standard" concrete and over time weaken the concrete until it fails under stress.

When it comes to heat-resistant concrete, one of the most important things to consider is the type of aggregate that you use. While there are a variety of different options out there, not all of them will stand up to the high temperatures that are often associated with this type of concrete.

That's why it's essential to do your research and choose an aggregate that will be able to withstand the heat.

One of the most popular options for heat-resistant concrete is refractory concrete. This type of concrete is made with a special type of aggregate that is designed to withstand high temperatures.

Additionally, refractory concrete is often reinforced with steel or other materials to increase its heat resistance further.

If you're looking for heat-resistant concrete that will be able to stand up to even the most extreme temperatures, refractory concrete is a great option to consider.

A  Recipe For Heat-Resistant Refractory Concrete

This mixture may be used for making our D.I.Y Furnace or any other small furnaces, pizza ovens, and other high-heat applications where regular concrete isn't suitable.


What you need:

  • River gravel or crushed fire bricks
  • Sand
  • Calcium Aluminate cement. (best grade available)
  • Lime (lime is usually cheaper, about 80% of the cement price)
  • Water (h2O)
  • You can add into this mix a little standard Fireclay if you like as it helps.


Mixture: (parts ratio is 3 x 2 x 2 x 0.5, plus water)

  • 3 shovels of gravel or crushed firebricks.
  • 2 shovels of sand.
  • 2 shovels of cement.
  • half a shovel of lime.
  • This amount will require approximately 6-7 liters of water to mix the concrete.


Mix all the dry ingredients together and slowly add the water mixing as you go until you get a mixture similar to normal concrete, not too wet but shapeable see the source article for a more detailed guide.

Safety: Always wear a proper respirator (not some simple dust mask) when working with dust, cement, and lime. All of which are terrible for your lungs.

Wear gloves, eye protection, and steel-capped shoes.

Take extra care when handling the lime (Calcium hydroxide):

Unprotected exposure to Ca(OH)2 can cause severe skin irritation, chemical burns, blindness, lung damage or rashes - Wiki

Source: See the Recipe source for more information.

What are you planning to make with refractory concrete? Let us know below.