How to Remove Mold From Shower Caulk (And Replace It), by DIY Playbook on YouTube. 1 min 25 s.
- Video length
- 1 min 25 s
- Time to do it
- 2 to 3 hours plus drying time
- Difficulty
- Medium
- Steps
- 9
What you need
Steps
Run a utility knife along both edges of the old caulk to break the seal against the tile and tub. Keep the blade flat so you do not gouge the surface.
Pull out the old caulk with a caulk removal tool or putty knife. Work in short sections and scrape out every bit of residue from the joint.
Clean the joint with mold and mildew cleaner or a diluted bleach solution. Scrub with a stiff brush, then wipe with a damp rag.
Wipe the area with rubbing alcohol and let it dry completely. Silicone will not stick to damp or dusty surfaces, so give it several hours.
Lay painter's tape along both sides of the joint to keep the silicone line neat. Leave a gap the width of the joint.
Load the silicone caulk into the caulking gun and cut the nozzle at a 45 degree angle. Cut it to roughly the width of the gap.
Push a steady bead of silicone into the joint, keeping the nozzle in contact with the surface. Overfill slightly so the joint is fully packed.
Smooth the bead with a wet finger or caulk tool in one continuous pass. Peel the tape off while the silicone is still wet.
Leave the silicone to cure for the time on the tube, usually 24 hours. Keep the shower dry and do not run water on it until fully cured.
Tips and common mistakes
Never caulk over old moldy caulk, because the mold will grow back under the new layer.
Silicone does not stick to silicone, so remove every trace of the old bead before applying new.
Peel the painter's tape before the silicone skins over, or it will pull up the fresh bead.
Work in a ventilated bathroom and wear gloves, since mold cleaners and silicone are harsh on skin.
Questions
Can I use grout instead of caulk around a tub?
No. Grout cracks where the tub and wall move, so use a flexible silicone caulk made for wet areas at that joint.
How long before I can use the shower again?
Wait until the silicone is fully cured, usually 24 hours. Check the tube for the exact time and keep the area dry until then.
What if the mold keeps coming back?
Mold returns when moisture stays trapped. Run the fan after showers and fix any leaks or loose caulk so water cannot sit behind the bead.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
