Silicone sealant is essential in bathrooms and kitchens: it seals the joints between the bath and the tiles, around the basin, the shower tray and the worktop. Over time, though, it darkens, gets black mould, peels away, and during renovation it often ends up where it should not be. Scraping silicone off dry is hard work: it stretches, tears and leaves a thin film that new sealant will not stick to.
WD-40 Multi-Use gets under the edge of the sealant, weakens its grip on the surface and helps you lift the bead off in one strip. Below is a step-by-step guide to preparing the area, removing the old silicone and getting the joint ready for a new bead.
What you will need
- WD-40 Multi-Use
- a silicone removal tool or plastic scraper, or a blade in a holder for hard surfaces
- protective gloves
- a rag or microfibre cloth
- warm water and washing-up liquid
- degreaser or alcohol for the final wipe
Important: Remove every trace of WD-40 before applying new sealant: lubricant and silicone can react, and the new bead will not bond properly. Wash the surface with warm soapy water and then degrease it.
Step 1
Prepare the work area
Clear the bath or worktop of anything you do not want to get dirty or break: bottles, mats, towels and small items. Keep the room ventilated and wear gloves. If there are decorative or delicate surfaces nearby, such as an acrylic bath or a painted wall, test the product on a hidden area first.
Step 2
Dry the joint
The surface and the sealant itself need to be dry. If the bath has just been used, wipe the joints with a cloth and let them dry. On dry silicone the product gets under the edge more easily and the tool does not slip, so the job is easier and safer.
Step 3
Apply WD-40 to the sealant
Spray WD-40 Multi-Use through the thin straw onto the edge or corner of the bead you want to remove. Work along a long joint in sections of 30-50 cm. Leave it for a few minutes to get under the silicone and loosen its grip.
Step 4
Lift the silicone with a scraper
Get the scraper under the edge of the bead and remove the sealant with push, pull and scraping motions. It often comes away as a long strip that you can pull by hand. Hold the tool at a shallow angle so you do not scratch the enamel, acrylic or tile glaze. If a section is still holding firm, spray it again and wait a few more minutes.
Step 5
Clean off sealant and WD-40 residue
Collect the silicone scraps in a bag and put them in the household rubbish; do not wash them down the drain. Wipe away any remaining film with a cloth.
Then wash the joint and the surrounding area thoroughly with warm water and washing-up liquid, rinse and dry. Finally wipe with degreaser or alcohol. New sealant should only go onto a clean, dry and degreased surface.
Tip: If there are dark mould stains under the old silicone, treat the joint with an anti-fungal cleaner after washing and let it dry for a day. New sealant applied over a damp or contaminated base will turn black again within a few months.
What next
Only apply the new bead once the surface is completely dry, and do not use the bath or shower until the sealant has cured according to the manufacturer's instructions. Keep your can of WD-40 Multi-Use handy afterwards for squeaky cupboard doors, stiff taps and protecting metal fittings from moisture.
These uses come from the experience of WD-40 users in many countries. Always follow the instructions and warnings on the product label.
More guides in «How to use».