A few lines of grout in my shower started cracking and crumbling, and I put off fixing them because I assumed the whole wall had to come down. Turns out you can repair just the broken grout in an afternoon, and it costs almost nothing. I wish I had known that a year earlier.

You Only Need to Remove the Bad Grout

The key is to remove the cracked or crumbling grout and leave the good stuff alone. A cheap grout removal tool or even a flathead screwdriver scrapes the damaged lines clean. Go slowly so you do not chip the tile edges.

How to Repairs It

1. Scrape out the broken grout down to clean, solid grout underneath.
2. Vacuum the gaps so dust does not stop the new grout from bonding.
3. Mix a small batch of grout and press it into the joints with a rubber float.
4. Wipe the excess with a damp sponge, then buff the tile clean.

The Detail People Miss

Matching the grout color is the tricky part. I grabbed a bright white grout and my existing lines were more of an off white, so the patch stood out. Take a chip of the old grout to the store and match it, or buy a small tub of pre mixed grout in a few shades to test. Also, let it cure fully before the shower gets wet again, usually at least a day.

Seal the new grout once it is dry, and it will hold up as long as the rest.