Short answer
If the caulk has black spots that won’t clean off, is peeling or cracked, or has gaps, replace it. The old caulk has to come out completely, the joint has to be cleaned and fully dry, and new 100% silicone has to cure before the shower is used.
Caulk is the seal between your tub or shower pan and the wall. When it fails, water gets behind the tile and into the wall, where it can cause damage you don’t see until it is expensive.
Signs it is time
- Black or pink spots that come back right after cleaning. Mold can grow under and inside old caulk.
- Caulk peeling away from the tub or tile.
- Cracks, gaps or missing sections.
- Hard water crust built up along the joint.
Why you can’t just caulk over it
New caulk doesn’t bond well to old caulk, soap scum or mold. It peels within months and traps moisture and mold underneath. The old caulk has to come out completely.
How a proper reseal is done
- Cut and scrape out all of the old caulk.
- Clean the joint of soap scum, mineral buildup and mold residue.
- Let it dry completely. Water in the joint ruins the seal.
- Apply a smooth, even bead of 100% silicone, color matched to the grout.
- Let it cure for the time on the label before running the shower.
When to call us
Call if you would rather have it done right the first time, or if the tile, grout or shower pan needs deep cleaning too. We remove old caulk and reseal with 100% silicone. See shower and tub caulk.
Text us a photo
Not sure what you are looking at? Text a photo of the problem to 480-264-0012 and we will tell you what it needs and get you a quote fast. Free estimates.
Last reviewed . This guide is general information. When in doubt, or for anything involving gas, wiring or major water damage, call a professional.