Repairing Cracked Granite at Sink Cutouts

Failed reinforcing rods cause cracks like the one in this Uba Tuba granite countertop.

The crack in this Bordeaux granite countertop was also caused by a failed reinforcing rod.

Supporting the flange of an undermount sink with a sink harness can help prevent the surrounding granite countertop from cracking.

Removing the face of the cabinet is necessary to gain access to the underside of the granite.

The face of a framed cabinet pops off easily once the screws holding adjacent cabinets together are removed.

A leaking sink flange can deliver water to the reinforcing rod, causing it to rust and expand, eventually cracking the granite.

To remove the rod, grind away the adhesive on both sides wherever the rod is rusted.

Covering the surrounding area with poly helps with the dust, but even using fans and a vacuum attachment on the grinder doesn't eliminate it all. It's important to make that clear to the homeowners ahead of time so they are not surprised.

Here you can see the underside of a repaired countertop. Once the rod was removed, the slot was cleaned with acetone and then packed with anchoring epoxy.

If the countertop has cracked extensively, prying the rod may result in the granite pieces falling away. In such cases, it's best to reinforce the granite before putting any pressure on the rod.

Hot-melt gluing blocks to the sink shoulders helps to keep the granite from falling apart while the rod is being removed.

A piece of melamine reinforced with a 1-by supports the granite pieces while they are being glued together.

Dani Clamps hold a solid-surface repair together during glue-up. For stone, the author wraps one clamp around another and uses more clamps.

The granite shown here was badly cracked. Cuts on the bottom and the sink-side at either end allowed a piece of granite to be neatly broken off so the rod could be removed without further damage.

The sink-side length of granite has been cleanly broken off, exposing the rod for easy removal.

Here is the Uba Tuba repair after glue-up and clamping, but before grinding and polishing.

The final step is to polish the repaired area.

The goal when polishing is to match the sheen of the existing top.

It's important to set client expectations. Though the repair will be inconspicuous, it will not be invisible.

Join the Discussion

Please read our Content Guidelines before posting

Close X