How do I remove a cracked hearth brick?

A firebrick is a fragile thing. It’s not an egg, of course, but it shares some of the same characteristics. If you treat it the right way, it will hold its form. But one tap in the wrong place, or pressure on the wrong spot, will result in a crack or a chip.

Most of those are minor, but if you’ve got a break in your cooking surface that you can’t live with, the BrickWood design lets you pop it out.

Sort of.

The firebrick surface uses no mortar (right? you didn’t mortar those firebrick into the hearth, right?), so in theory you should be able to slide a single brick up out of its hole and slip in a new one. In practice, that’s hard because every brick surface is butted tightly up against every other. So, how do you work with an unworkable proposition like that?

Construction glue to the rescue!

For example, all-purpose Gorilla Glue will work great for this task. It bonds tightly to brick (among many other materials) and won’t let go. Ever.

While installing my hearth, I had a deep chip crack off the corner of one brick (of course, it was the last brick I was leveling, it was under the most stress, and it is in the front of the hearth where that missing piece will do the least good). I left it until I was ready to do my first firing, just in case other defects showed up.

I took one of my cut-off firebrick, applied Gorilla Glue, plopped it on top of the broken brick, and waited 2 hours for it to set up. This particular adhesive works by absorbing moisture from the atmosphere and from whatever material to which it is applied. The moisture starts a reaction in the glue (which will develop a frothy appearance during curing), and the end result is a very, very…very strong bond.

With this newly-handy handle installed, it was a simple matter to pull up the old brick, ensure there were no stones in the underlying sand, and tap a new brick into place.

The new brick is the darker one in this image. It wasn’t dark for long!

You don’t have to live with chips and breaks on your beautiful herringbone hearth. Any brick that is not mortared in under the edges is fully replaceable.

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