Seal the deal

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Water damage in your home caused by seepage between tiles, at joints in the wall or between the wall and bath/shower is not only unsightly but can be expensive to repair. Fortunately preventing this from happening is one of those DIY tasks you can easily tackle as long as you prepare the surfaces properly, show the necessary patience and get good quality sealants and all the tools you need from your consumer champion Cashbuild.

Keep damp from creeping up between tiles, where walls meet, in the bath or in the shower pan with these handy tips from Cashbuild

Here we focus on sealing the bath but these steps also apply to your shower pan, kitchen sink and anywhere else that sealant may be needed to prevent water damage.

You'll need

Silicone Sealant; Fixed Blade; vacuum cleaner; acetone; sponge; silicone caulking gun; drying cloth; paper towels; dishwashing liquid; mildew cleaner

Step 1

Remove the old silicone

Carefully slide the blade of the Fixed Blade between the silicone and the surfaces to which the sealant is attached. Important Slide the knife away from you, not towards you.

When the sealant has been loosened from the bath and the wall, use the blade to cut the silicone into sections 5-8 cm long. Slip the blade back under the sealant and lift it out section by section. Remove any remaining remnants of silicone by gently scraping it off with the knife blade.


Be careful to keep the blade at a low angle so you don't scratch the tub.

Step 2

Clean the surface

Make sure no bits of sealant have remained in the joint by vacuuming the cleaned area. Wipe the bath edge and wall which are now sealant-free with acetone. Allow to dry for a few minutes. Use a concentrated mildew killer after wiping with acetone if the area you're resealing was heavily mildewed. Wipe off any residue with a sponge after a few minutes. Rinse the sponge frequently in hot water. Allow the surface to dry overnight.


The area must be completely dry before the new silicone is applied or it won't stick properly

Step 3

Reseal the surface

Fill the bath to just below the overflow as the weight of the water will settle the bath slightly lower. This will help ensure the seal lasts longer as it won't be stretched when you get into the bath.

Prepare the silicone sealant tube by cutting the applicator nozzle at a slight (30-45 degree) angle so it will fit snugly against the area where the wall and bath rim meet. Make sure you cut the nozzle at a spot where the size of the hole matches the gap you're sealing. Pull the pressure rod of the silicone caulking gun back to allow you to load the silicone sealant tube. Squeeze the trigger carefully until the pressure rod goes into the base of the cartridge. Position the applicator nozzle against the surface you're re-sealing. Gently squeeze the trigger until the silicone starts to come out.

Apply a small but constant bead of silicone all the way around the edge of the bath. The simplest way to get a neat finish is by using your finger to smooth the sealant: dip it in dishwashing liquid and draw it along the bead of silicone. Have a supply of paper towels and dishwashing liquid ready for wiping off excess silicone or mistakes. Don't leave a bead of sealant for more than a few minutes as it will harden and become impossible to smooth.


It's important to push the silicone into the joint rather than pull the gun along the top of the joint. For a smoother finish try to apply the silicone in one stroke.

Final touches

Wait for 24 hours then use a damp cloth to wipe off the dish-washing liquid you've used for smoothing the silicone. As soon as the surface is dry the bath-room is protected.


Trying to wash silicone off your hands with water just makes it adhere more – use dishwashing liquid.

  • Visit your nearest Cashbuild store and talk to a friendly consultant for advice on how to seal other home surfaces
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