Silicone is the flexible seal that sits where two surfaces meet: where the shower wall meets the shower base, where the bath meets the tiles, where the benchtop meets the splashback. Unlike grout, silicone is designed to stretch as the house moves and as fixtures expand and contract with heat. It is also one of the first things in a wet area to fail. It goes black with mould, peels away at the edges, splits along the corner, or simply comes away in a strip.

When silicone fails, water gets in. In a shower, that means water behind the tiles and under the base, potentially causing rot, mould and damage. In the kitchen, water seeps behind the benchtop into the cabinet. We replace silicone and caulking in homes across Berwick, Narre Warren and the City of Casey. Done properly, a fresh silicone job keeps water out, looks clean and lasts years.

Where we replace silicone

• Shower bases and internal shower wall corners
• Around bath edges and bath hobs
• Shower screen frames (where they meet tiles and bases)
• Vanity tops and basins against walls
• Kitchen benchtops at splashbacks and around sinks
• Laundry troughs and benches
• Toilet pan bases to floor (where appropriate)
• Window frames internally
• Floor-to-wall junctions in wet areas
• External gaps around window and door frames (with suitable sealants)

Why silicone fails

Mould

Most silicone in bathrooms contains mould inhibitors, but over time, particularly in poorly ventilated rooms, mould grows into the surface and below it. Once silicone is black inside, it cannot be cleaned back to white.

Loss of adhesion

Silicone needs a clean, dry surface to stick to. If it was applied over soap scum, old silicone or a damp surface, it will start peeling early.

Movement

Houses move, and baths and shower bases flex when someone stands in them. Silicone that is too thin, or applied without proper joint shape, can split under movement.

Age and cleaning

Harsh cleaners, scrubbing and UV from windows break silicone down over years.

Our process

1. Remove all old silicone

New silicone does not bond to old silicone. We cut out the old bead with blades and specialist tools, then remove residue with a silicone remover and scrapers. This is the slowest part of the job and the most important.

2. Clean and treat mould

We clean the joint, remove soap scum and treat any mould remaining on the surfaces either side, so it does not grow back through.

3. Dry

Silicone must go onto a dry surface. In showers, we make sure the joint is dry, which may mean using a fan or waiting.

4. Apply the right sealant

We use a sanitary-grade silicone with mould inhibitors for wet areas, in a colour that suits the tiles and grout. Kitchen and laundry joints may use a different sealant. For painted areas, we use paintable acrylic caulk instead, since silicone cannot be painted.

5. Tool a neat bead

A good bead is shaped so water runs off, filled into the joint fully and has crisp edges. We tool and finish each bead cleanly.

6. Cure

Silicone needs time to cure before it gets wet. We will let you know how long, usually a day before showering.

Silicone versus grout

Grout is rigid and goes between tiles on flat surfaces. Silicone is flexible and goes at changes of plane, such as internal corners and where tiles meet a different material. Using grout in a corner is a common mistake because it cracks when the house moves. Using silicone between flat tiles is also a mistake because it collects dirt. We use each in its proper place. For grout issues see tiling and regrouting.

Silicone and leaks

Fresh silicone can stop water getting in through a failed joint, but it cannot fix a failed waterproofing membrane underneath the tiles. If we see signs of a leaking shower, such as stains outside the shower, swollen frames or wet skirting boards, we will tell you before resealing. A shower that leaks through the membrane needs a qualified waterproofer.

Colours

Clear, white, grey, beige, black and many tile-matched colours are available. Clear can look dirty over time as mould grows beneath. White and grey are the most common choices for showers. We match the colour to your grout or tiles where possible.

Kitchen and laundry sealing

Benchtop joints at the splashback and around undermount and drop-in sinks keep water out of cabinets. Failed sealing here can lead to swollen particleboard and cabinet damage. We remove old sealant, clean, and reseal using a sealant suited to the benchtop material: laminate, stone or timber. See also kitchen cupboard repairs for swollen cabinets.

Caulking for painting

Before painting, gaps between skirting boards and walls, architraves and walls, and cornice joints should be filled with paintable caulk. This gives clean lines and hides small gaps that open as the house moves. We can caulk before your painter arrives, or as part of painting touch-ups.

External sealing

Gaps around external window and door frames let in water, draughts and insects. We use external-grade sealants to seal frames where they meet cladding or brickwork, taking care not to block weep holes or drainage paths, which are there to let water out.

Keeping new silicone clean

• Ventilate the bathroom well; run the exhaust fan during and after showering
• Squeegee or wipe down shower corners after use
• Avoid harsh abrasive scrubbing on silicone
• Clean with a mild bathroom cleaner regularly
• Treat early mould spots before they get into the silicone

In Casey homes

Bathrooms in established homes around Hampton Park, Hallam, Narre Warren and Berwick often have silicone that has been patched over several times. Newer homes in Lynbrook, Lyndhurst and Narre Warren South may need silicone redone in the first few years as the building settles and initial joints open up. For rental properties, fresh silicone is one of the most effective ways to present a clean bathroom between tenants.

Related services

• Tiling and regrouting
• Bathroom fixtures and accessories
• Kitchen cupboard repairs
• End-of-lease and rental repairs

Areas covered

Silicone and caulking across Berwick, Narre Warren, Narre Warren South, Narre Warren North, Narre Warren East, Hallam, Hampton Park, Lynbrook, Lyndhurst and Harkaway.

Shower screens and silicone

Framed and semi-frameless shower screens are sealed with silicone where the frame meets the tiles and the base. When this seal fails, water escapes onto the bathroom floor. We remove and reseal screen frames, making sure the base track has its drainage gaps clear so water inside the frame can drain back into the shower. Adjusting or replacing screens themselves is glazier work.

Bath seals that keep failing

Baths flex when filled with water and when someone gets in, so the joint between the bath and wall moves more than most. A common trick is to fill the bath with water before sealing, so the joint is sealed at its widest position and does not stretch as much in use. We use this approach and a sealant suited to the movement.

Window sills and condensation

Bathrooms, bedrooms and kitchens often get condensation on windows in winter, which runs down and sits on the sill. Over time the silicone or caulk around internal window frames goes mouldy and lets moisture into the timber. Replacing the seal and treating the mould helps, and so does better ventilation.

Small jobs that make a big difference

Replacing silicone is one of those jobs that is hard to do well yourself, because removing the old silicone completely is slow and fiddly, and laying a neat bead takes practice. It is also one of the most visible improvements in a bathroom. Fresh, white, clean silicone lines make the whole room look cleaner. Many customers combine it with regrouting, replacing towel rails or fixing a dripping-looking shower screen in one visit.

Gaps between benchtops and walls

In many kitchens, the back edge of the benchtop does not sit perfectly against the wall, especially where walls are slightly out of true. A neat bead of sealant hides the gap and stops crumbs and water getting down behind the cabinets. Where the gap is wide, we may use a backing rod first so the sealant is the right depth and does not sag.

Expansion joints and floors

Large tiled and concrete areas need movement joints so they can expand and contract without cracking. These joints, usually filled with flexible sealant, can perish or come out over time. We can remove failed sealant from movement joints in tiled floors and alfresco areas and refill them with a suitable flexible product.

Toilets and floor seals

Where a toilet pan meets the floor, a neat bead of sealant can stop cleaning water getting underneath and hide the gap. Practice varies on whether to seal all the way around, because a fully sealed pan can hide a leak. We generally leave a small section at the back unsealed so any leak shows. If the toilet rocks or leaks at the base, it needs a plumber first.

External doors and windows

Exposed timber and aluminium frames on external walls can let water in where their seals have perished. We replace external sealant with products rated for UV exposure and movement, and check that weep holes in window frames are not blocked so water can drain away.

Products we use

Not all silicones and sealants are the same. Sanitary silicones with mould inhibitors suit bathrooms and kitchens. Neutral-cure silicones are gentler on natural stone, mirrors and some metals. Acrylic gap fillers suit painted interior joints. Polyurethane and hybrid sealants suit some external and movement joints. We choose the product to suit the joint, not just whatever is in the van.

Frequently asked questions