Silicone is the flexible seal between surfaces that move differently: the bath and the wall tiles, the shower base and the screen, the benchtop and the splashback, the vanity and the wall. When it is new, it is clean, white and waterproof. Over time it turns black with mould, shrinks, cracks and peels away. Once that happens, water gets behind it, into the wall, under the floor or into the cabinet below. Failed silicone is one of the most common causes of hidden water damage in bathrooms and kitchens.

We remove and replace silicone in showers, baths, vanities, kitchens and laundries, and caulk gaps around windows, doors, skirting and trims, in homes and rentals across Traralgon, Morwell, Moe, Newborough, Churchill and the surrounding district.

Why silicone goes black

The black spots in old silicone are mould growing in and under the sealant. In damp bathrooms with poor ventilation, which describes many Valley homes in winter, mould grows quickly. Surface mould can sometimes be cleaned off, but once mould has grown into the silicone, cleaning will not remove it. The only fix is to cut out the old silicone, kill the mould underneath, and reseal.

Our silicone replacement process

1. Remove all the old silicone. We cut and scrape out every bit of old sealant with a blade and silicone removal tools, without scratching the bath, tiles or acrylic.

2. Clean off residue. Silicone residue stops new silicone sticking. We use a remover and solvent to clean the joint.

3. Treat mould. We treat the joint with a mould killer to reduce regrowth.

4. Dry the joint thoroughly. Silicone will not bond to a damp surface. We make sure the joint is dry before resealing.

5. Fill deep gaps. Where the gap is deep, we use a backing rod so the silicone is the right depth and flexes properly.

6. Apply new silicone. We use a quality sanitary-grade, mould-resistant silicone in the right colour, usually white, clear or a grey to match grout.

7. Tool a neat bead. We smooth the bead for a clean, even finish that sheds water.

8. Leave it to cure. The area should not get wet for at least 24 hours (check the product used; some need longer).

Baths: fill them first

Baths flex when filled with water and a person. If you silicone an empty bath, the joint stretches and cracks the first time it is used. For baths, we fill the bath with water before sealing, so the joint is sealed at its loaded position, then drain it after curing.

Where we replace silicone

Bathroom

• Shower base to wall tiles
• Shower screen frame to tiles and base
• Bath to wall tiles and bath hob
• Vanity top to wall and splashback
• Toilet base to floor (where appropriate)
• Internal tile corners in showers (where silicone has been used instead of grout)

Kitchen

• Benchtop to splashback
• Sink to benchtop
• Benchtop joints and end panels

Laundry

• Laundry tub to wall and cabinet
• Benchtop to wall

Windows, doors and trims

• Gaps between window frames and walls, inside and outside
• Door frames to walls
• Skirting boards and architraves to walls (painter’s acrylic gap sealant, which can be painted)
• Gaps around pipes and penetrations

Silicone vs acrylic caulk vs grout

• Silicone stays flexible and waterproof, but cannot be painted. Use it in wet areas and where surfaces move.
• Acrylic gap sealant is paintable and suits gaps in dry areas between skirting, architraves and walls.
• Grout fills the joints between tiles. It is rigid and should not be used at internal corners or where the tiles meet a bath, shower base or benchtop, because those joints move. See tiling and regrouting.

Using the wrong product is a common reason seals fail early.

Signs your silicone needs replacing

• Black or grey mould spots that will not clean off
• Gaps, splits or cracks in the bead
• Silicone peeling away from the tiles or bath
• Water marks or swelling on the vanity, skirting or floor near the shower
• Musty smell in the bathroom
• Loose or drummy tiles near the shower base

If you see swelling or loose tiles, water may already be getting into the wall or floor. Resealing will stop further water getting in, but damage behind the tiles may need a waterproofer or plumber to inspect.

Silicone and waterproofing

Silicone is not waterproofing. Behind the tiles in a shower, there should be a waterproof membrane that stops water reaching the walls and floor. Silicone is the first line of defence at the joints, but if a shower is leaking through the tiles or floor, that is a waterproofing failure and needs a registered waterproofer or a bathroom renovation. We will tell you if we see signs of that.

How long does silicone last?

In a well-ventilated bathroom that is cleaned regularly, good silicone lasts several years. In a damp bathroom without an exhaust fan, it may go mouldy within a year. Rental properties are worth resealing between tenancies.

Rentals and property managers

Mouldy silicone is one of the most frequent items on routine inspection reports and end-of-lease checks. It’s also a good preventive maintenance item. We reseal showers, baths, vanities and kitchens in rentals for landlords and agents, and send before-and-after photos.

Areas we cover

Silicone replacement across Traralgon, Morwell, Moe, Newborough, Churchill, Yallourn North, Glengarry, Tyers, Traralgon South and Hazelwood North.

Keeping new silicone clean

• Run the exhaust fan during and for 10 to 15 minutes after showers.
• Squeegee or wipe the shower walls and the silicone line after use.
• Leave the shower screen door open to air out.
• Clean regularly with a bathroom cleaner. Avoid harsh scrubbing pads on silicone.
• Use a mould spray occasionally on the silicone line, following the label.

Silicone colours and types

Silicone comes in many types, and the right one matters:

• Sanitary or bathroom silicone contains fungicide to slow mould growth. It is the standard for showers, baths and vanities.
• Neutral cure silicone has low odour and doesn’t corrode metals, so it suits mirrors, metal frames and natural stone. Some stone can stain from the wrong silicone, so we use a stone-safe product on marble and granite.
• Acetic cure silicone smells of vinegar while curing. It bonds well to glass and tiles but can damage mirror backing and some metals.
• Kitchen silicone for benchtops and sinks needs to be food-area safe and mould-resistant.
• Exterior silicone and polyurethane sealants for windows, doors and cladding gaps need UV resistance and movement capability.

Colours include white, clear, translucent, black, and greys and beiges to match grout. Clear silicone shows mould and dirt underneath more than white does, and it yellows in sunlight. For most bathrooms, white or a grout-matched colour gives the cleanest look.

Draughts and gaps around windows

Older Latrobe Valley homes can be draughty in winter. Gaps between window frames and walls, around door frames and where architraves have shrunk let cold air in and warm air out. Sealing these gaps with a suitable sealant is a cheap way to make a home warmer and reduce heating bills. Outside, gaps between window frames and cladding should be sealed to keep rain out. We seal gaps inside and out, and can add weather seals to doors. Weatherboard homes need care, because some gaps are meant to let the wall breathe and drain. We seal only where sealing is appropriate.

Shower screens and the silicone line

Framed shower screens are sealed to the tiles and base with silicone along the outside of the frame. The inside of the frame should usually be left unsealed at the bottom so water that gets inside the frame can drain back into the shower. Sealing both sides traps water in the frame. We follow the screen manufacturer’s guidance, and we check for weep holes and make sure they are clear.

Toilet pans

In Victoria, the base of a toilet pan is commonly sealed to the floor. Some plumbers recommend leaving a small unsealed gap at the back so a leak shows up quickly rather than hiding under the pan. We can reseal around a toilet base with mould-resistant silicone, but a leaking toilet connection or a rocking pan needs a plumber.

Getting a quote

Email photos of the joints that need resealing, including close-ups of any mould, swelling or loose tiles. Tell us how many showers, baths and vanities need doing. We will reply with a clear scope and quote.

Why DIY silicone often fails

Resealing a shower looks easy, and plenty of people try it. The common reasons DIY silicone fails within months are:

• Old silicone left in place. New silicone does not bond to old silicone or its residue.
• Wet or damp joint. Silicone applied over moisture does not stick, and mould grows behind it.
• Mould not treated. Spores left in the joint grow back through the new sealant.
• Wrong product. Acrylic or general-purpose sealant in a shower breaks down quickly.
• Bead too thin or too thick. A thin bead tears, and a thick blob traps dirt and peels at the edges.
• Used too soon. Getting the silicone wet before it has cured ruins the seal.
• Bath sealed empty. The joint stretches and cracks when the bath is filled.

If you want to try it yourself, avoiding those mistakes will give you a much better result. If you’d rather have it done properly and quickly, we can do it, often in a couple of hours for a typical bathroom.

Bathrooms with several showers, or a whole block of rental units, can usually be resealed in a single day, which keeps disruption for tenants to a minimum.

Frequently asked questions