Silicone is the flexible seal in the places where two surfaces meet and move: where the bath meets the wall tiles, around the shower base, along the back of the kitchen benchtop, around the basin and toilet base, and around windows and door frames. When it is fresh it is invisible. When it fails it is the first thing you notice: black mould spotting along the bath, a peeling strip at the back of the shower, gaps where water runs behind the vanity, or yellowed, cracked caulking along skirtings and window frames. Replacing silicone and caulking is a small job with a big effect, and it is one of the most practical ways to protect a bathroom, kitchen or laundry from water damage. We reseal wet areas, kitchens and joinery in homes and rentals across Dandenong and the surrounding suburbs.

Where we replace silicone

• Shower screens, shower bases and internal corners of shower walls
• Around baths, including the bath-to-wall junction and bath hobs
• Basins, vanities and vanity tops against the wall
• Toilet pans at the floor, where appropriate
• Kitchen benchtops against splashbacks, and around sinks and cooktops
• Laundry tubs and cabinets
• Window frames, inside and out
• Door frames and thresholds
• Wet area floor and wall junctions
• Expansion joints in tiled floors and outdoor areas

Where we use caulking

• Gaps between skirting boards and walls
• Joins between architraves and walls
• Cornice joints and ceiling junctions before painting
• Gaps around window and door frames before painting
• Small gaps in timber trims and joinery

Why silicone fails

Mould

Black spots on silicone are mould growing on and into the sealant. In a humid bathroom, mould feeds on soap scum and body oils on the surface and eventually grows into the silicone itself. Once mould is inside the silicone, cleaning only lightens it temporarily; the only real fix is removing the silicone and starting fresh.

Movement and age

Baths, shower bases and benchtops move slightly as they are loaded and as the house expands and contracts. Over years, silicone loses its flexibility, hardens and pulls away from one surface, leaving a gap that lets water through.

Poor application

Silicone applied over old silicone, onto wet or dirty surfaces, or over soap residue does not bond properly and peels away within months. Using the wrong product, such as an acrylic caulk in a shower, also fails quickly.

Why failed silicone matters

A gap in the silicone at the back of a shower or bath lets water run behind the tiles and under the bath or vanity every time it is used. Over months this can soak the wall framing, damage the floor, rot vanity cabinets, cause mould inside walls, and create the musty smell of a hidden leak. On the other side of a shower wall, it may show up as peeling paint, swollen skirting boards or damp carpet. Resealing early is far cheaper than repairing water damage later.

How we replace silicone properly

Remove every trace of the old seal

We cut out the old silicone with blades and specialist tools, then remove the remaining residue with a silicone remover. New silicone does not stick to old silicone, so this step is essential.

Clean and treat

The joint is cleaned of soap scum and residue and treated to kill remaining mould spores, then cleaned again with a solvent so the surface is free of grease.

Dry thoroughly

Silicone will not bond to wet surfaces. In showers and baths, this often means the area needs to dry for several hours, and we may use a fan or heat gun to help. We ask that the shower or bath is not used for some hours before our visit if possible.

Apply the right product

We use a quality neutral-cure or sanitary-grade silicone with mould inhibitors for wet areas, in a colour matching the existing grout or fixtures, usually white, clear or translucent. Joints are masked where needed for perfectly straight lines.

Tool to a neat finish

The bead is tooled smooth with the correct profile, so water runs off rather than sitting on it, and the masking is removed while the silicone is still wet for a crisp edge.

Allow to cure

Silicone needs time to cure before getting wet. Most wet-area silicones need around 24 hours before the shower or bath is used, though it depends on the product, temperature and humidity.

A tip for baths

When resealing around a bath, we fill the bath with water before applying silicone, if the bath type allows. The weight of the water pushes the bath down to its loaded position, so when it is emptied after the silicone cures, the seal is slightly compressed rather than stretched each time someone gets in. This simple step makes the seal last noticeably longer.

Silicone or grout in corners?

Internal corners of shower walls, the junction between walls and floors, and where tiles meet baths and benchtops should be sealed with silicone, not grout. These are movement joints: the surfaces move slightly relative to each other, and rigid grout cracks there. If your shower corners are grouted and cracking, we rake out the grout and replace it with silicone. See our tiling and regrouting page.

Kitchen benchtops and sinks

The silicone between the benchtop and splashback stops water and food from getting down behind the cabinets. Failed seals around an inset sink let water drip into the cabinet below, swelling the particleboard and causing the bench edge to blow. We reseal benchtop junctions and sinks with food-safe sanitary silicone, and can repair water-damaged cabinet bases through our kitchen and cupboard repairs service.

Windows and external sealing

Gaps around window and door frames let in draughts, dust and sometimes water during driving rain. External sealing uses UV-stable, paintable or weatherproof sealants suited to outdoor conditions. Internally, paintable acrylic gap filler closes gaps between frames and walls before painting. Sealing gaps also improves energy efficiency, making homes easier to heat in winter and cool in summer.

Caulking before painting

Gaps along skirting boards, architraves and cornices are filled with paintable acrylic gap filler before painting. This gives clean, continuous paint lines and hides small movement gaps. Caulk is different from silicone: silicone cannot be painted over, so it should never be used where paint will be applied. See our painting touch-ups page.

Resealing for rentals

Mouldy silicone in bathrooms is one of the most common items on routine inspection and end-of-lease reports. In Victoria, mould caused by building issues is generally the landlord’s responsibility, while mould caused by a renter’s use may be the renter’s. Resealing before handover usually resolves it. See our end-of-lease repairs and property managers pages.

Choosing the right sealant

Sanitary silicone

Formulated for bathrooms and kitchens, with fungicides that resist mould. The right choice for showers, baths, basins and benchtops.

Neutral-cure silicone

Neutral-cure silicones release less odour as they cure and are safe on a wider range of surfaces, including some metals, stone and mirrors, where acetic (vinegar-smelling) silicones can cause corrosion or staining. Natural stone such as marble may also need a specific stone-safe sealant to avoid staining the edges.

Acrylic gap filler

Water-based and paintable, ideal for gaps in trims, skirting boards, cornices and architraves before painting. It is not suited to areas that get wet regularly.

Polyurethane and hybrid sealants

Tough, flexible sealants for outdoor joints, concrete expansion joints and areas with greater movement. Many are paintable and UV-stable.

Fire-rated sealants

Penetrations through fire-rated walls in commercial buildings and units need fire-rated sealants. This work is often part of a compliance process and may need certification, so we will advise when a specialist is needed.

Ventilation: the key to long-lasting silicone

New silicone stays clean much longer in a bathroom that dries out quickly. Run the exhaust fan during showers and for at least 15 to 20 minutes afterwards, open a window if you can, squeegee shower walls and the screen, and leave the shower door ajar so air can circulate. If the exhaust fan is weak, noisy or not venting outside, an electrician can replace it, which is often the single best thing you can do against bathroom mould.

Signs you need resealing

• Black spots or pink staining on the silicone that will not clean off
• Silicone peeling, lifting or shrinking away from the tile or bath
• Gaps you can push a fingernail into
• Water appearing on the floor outside the shower or under the vanity
• Swollen or stained skirting boards or vanity bases near wet areas
• A musty smell in the bathroom that lingers even when it is clean
• Hardened, yellowed or cracked caulk along trims and windows

If you notice any of these, resealing now prevents larger repairs later.

Resealing for older residents and accessible bathrooms

Showers in accessible bathrooms often have a level or near-level entry, with a hob-less floor that relies on correct falls and sound sealing to keep water in the shower zone. Failed silicone at the junction of the floor and walls in these showers can let water escape quickly. When we install grab rails through our aged care and disability rails service, we also check and reseal around the shower, so the whole bathroom is safe and watertight.

We also check grab rail fixings and shower screen seals at the same time, sealing any gaps around screws so water cannot track into the wall cavity.

When the job is done, we leave written cure times and simple care tips so the new seals stay clean.

Areas we cover

We replace silicone across our service areas, including Dandenong, Keysborough, Eumemmerring and Springvale South.

Related services

Resealing pairs well with tiling and regrouting, bathroom fixtures and accessories, kitchen and cupboard repairs and window and flyscreen repairs.

Frequently asked questions