How to re-caulk anything

Tubs, sinks, windows or trim: swap the old line for a clean, sealed one.

Time: 30 min · Difficulty: Easy · 7 steps

What you need

Pick the right caulk
Anywhere that gets wet, like a tub, shower or sink, use 100% silicone. On trim, baseboards and walls you’ll paint, use paintable acrylic latex. Outdoors, choose a tube labeled for exterior use.
Tip: wet = silicone, paint = acrylic
Scrape out the old caulk
Slice along both edges of the old bead with a utility knife or scraper, then peel it out. Get every last bit.
Tip: new caulk won’t stick to old
Clean, dry and tape
Wipe the gap with rubbing alcohol and let it dry completely. Run painter’s tape along both sides, leaving a thin gap where the caulk will go.
Tip: bone dry before you start
Cut the tip
Cut the nozzle at an angle, with a hole about the size of the gap. Poke through the seal inside and load the tube into the gun.
Tip: start small, you can go bigger
Run one steady bead
Hold the gun at an angle and squeeze gently as you move along the gap at an even speed. Fill the gap without piling it up high.
Tip: slow and steady
Smooth it, peel the tape
Run a damp finger along the bead in one smooth pass: soapy water for silicone, plain water for acrylic. Pull the tape off right away, before the caulk skins over.
Tip: pull the tape while it’s wet
Let it cure
Keep water and paint off it until it sets. Silicone usually needs a full day before it gets wet, and acrylic can usually be painted after about 2 hours. Your tube has the exact time.
Tip: the tube knows best