How Often to Replace Fire Bricks?

When there is damage

Fire bricks should be replaced as soon as you see them starting to crumble, or in other words, be falling off inside the firebox.

Cracks don’t automatically mean that you have to get that particular brick changed right away. As long as the firebrick is actually still standing in one piece, there isn’t much to worry about.

If the crack does look a bit too much, you can always just get it replaced. You may also try filling that opening with some fire cement instead – this can work great as well.

What to get?

The most important thing to keep in mind is the size, obviously. So before purchasing any firebrick you stumble into for replacement, make sure that it matches the current size of what you have inside your wood burner.

But it is always best to follow the manufacturers recommendations. So if you have any manual that came with your wood stove or furnace, read it and get the information necessary.

This option from Amazon (link) should work on many of the stoves out there.

How do firebricks get damaged?

The primary reason why has all to do with how you load the stove, furnace, fireplace or what have you.

If you hit the brick just a bit too hard with the wood split you’re loading, you can crack it. Do that over and over again and you have a firebrick that is only going to fail.

I mean, there are people who burn wood for decades and never had replaced any of the fire brick inside their heating appliance. And that is mostly because they take their time when loading the firewood.

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Another potential factor is the moisture of the wood you’re burning.

It is known that some types of firebrick can suck up moisture. That means if you burn firewood which is not properly seasoned, the brick may come in contact with the water that gets out, turning brittle.

Why firebricks are important

They protect the inside and outside of your wood heater.

In other words, if the firebrick you have is faulty, it’ll compromise the structure of, for example, the wood stove itself; the metal can crack, you name it.

That is because all the flames are coming in direct contact with the metal. The bricks absorb most of that heat and lets it radiate how it’s supposed to – right into your room.