Commercial washroom and wet-area sealing
Commercial washrooms, showers, changing rooms, kitchens and wet areas resealed with sanitary anti-mould silicone, phased so some facilities stay open.
- Black mould growing into sealant that cleaning won’t remove
- Leaks from showers into ceilings or rooms below
- Sealant peeling from vanity tops, trays or worktops
Commercial washroom and wet-area sealing: send details for a fixed quote
Send drawings, photos or a joint schedule, or tell us about the site, and we’ll come back with a fixed quote.
What commercial washroom and wet-area sealing covers
Washroom sealant takes more punishment than almost any other joint in a building. It sits wet for long periods, faces strong cleaning chemicals and is in constant view of staff, customers, guests or pupils. Once mould grows into a bead it rarely comes out with cleaning, and once sealant lets go at a shower tray or vanity top, water gets into the floor, the wall or the room underneath. We reseal commercial washrooms, toilets, showers, changing rooms, accessible toilets, kitchens and tea points in offices, hotels, schools, healthcare buildings and gyms. Old sealant is removed in full, each joint is cleaned and given time to dry, and new sanitary silicone with anti-mould additives goes in, or a hygienic sealant where the area calls for it. We phase the work so that some facilities stay open while others are being sealed and left to cure.
We work across South East England, Greater London and all of Scotland. Our workmanship carries a 12-month guarantee, we’re CHAS accredited and a Constructionline member, and our applicators hold CSCS cards.
Problems we put right
- Black mould growing into sealant that cleaning won’t remove
- Leaks from showers into ceilings or rooms below
- Sealant peeling from vanity tops, trays or worktops
- Washrooms that look tired to staff, guests or pupils
- Too many facilities to close at once
- Gaps around fittings that trap dirt and moisture
Joints and areas we seal
- Vanity units and basins
- IPS panels and cubicles
- Urinals and WCs
- Showers, trays and wet room floors
- Accessible toilets and changing rooms
- Kitchens and tea points
At a glance
- Fixed quote, scope in writing
- CSCS-carded applicators
- CHAS accredited · Constructionline member
- £5m public liability insurance
- 12-month guarantee
How it works
- Tell us how many washrooms or wet areas need doing, with photos and your site hours.
- We agree an order that keeps enough facilities open, and send a fixed quote.
- Each area is closed off and the failed sealant cut out completely, including thin films left on surfaces.
- Joints are cleaned, mould on surrounding surfaces is treated, and the joints are left to dry.
- Sanitary anti-mould silicone, or a hygienic sealant where specified, is applied and tooled neatly.
- Cleaning teams are told when each area can go back into use.
Why mouldy sealant is replaced
Mould in wet areas often grows into the sealant itself rather than sitting on the surface, which is why bleach and scrubbing stop working. Sealing over the top traps it underneath, and new silicone won’t bond to the old. The lasting treatment is removal: strip the bead, let the joint dry out after cleaning, then lay fresh anti-mould sanitary silicone. Good ventilation and regular cleaning then help it stay clean for longer.
Phasing in busy buildings
Offices, schools, hotels and gyms can rarely lose all their toilets or showers at once. We plan washrooms in an order that keeps facilities available on each floor or wing, and your staff know when each area reopens. Tell us your site hours and access windows and we’ll plan around them. Where a building has more than one accessible toilet, we plan the order so one stays available.
Healthcare and food areas
In hospitals, clinics and care homes, your trust’s estates and infection-control requirements and any site permits come first, and we work within them. In kitchens and food areas, smooth, sealed joints help keep surfaces easy to clean, and food-safe or hygienic sealants are used where food contact is possible. Tell us the site rules when you send details and we’ll plan the work within them.
Choosing the sanitary product
Not every wet-area joint takes the same sealant. Sanitary silicone with anti-mould additives suits most washroom joints; hygienic sealants are used in food areas and where the specification asks for them; and where a joint meets natural stone or certain metals, a neutral-cure product is the safer choice, because acetoxy silicone can mark or attack some surfaces. Colour can be chosen to suit fittings and tiles within the product’s range.
Why it’s worth doing now
In a busy washroom, failed sealant shows up first as black mould that no amount of cleaning removes, then as water getting behind panels, under trays and through to the floor below. Replacing it restores a clean, sealed finish and stops small leaks becoming repairs.
What affects the quote
We don’t publish set prices, because no two buildings are the same. Send details and we’ll give you a fixed quote before we start. The main things that affect it are:
- How many metres of joint there are, and how many areas, elevations or sites
- How much failed sealant has to come out, and how hard it is
- Joint size, depth and whether backing rod or primer is needed
- Access: height, scaffold or MEWP access arranged by others, occupied areas
- The product the joint needs (and colour, where it matters)
- Programme, phasing and site requirements such as permits and inductions
What a good quote includes
- All failed sealant removed, never sealed over
- The product named for each joint type
- What the 12-month guarantee covers
- When each area can be used again
- Who is doing the work, their CSCS cards and the insurance in place
- What site paperwork and records are included
Aftercare
Keep extract fans working and doors able to vent. Ask cleaners to use the products the sealant maker recommends, to avoid scouring pads, and to report splits or black spots early. Give new joints their full cure time before showers and floors are washed down.
Trusted. Accredited. Insured.
Commercial washroom and wet-area sealing: common questions
Can the mould be cleaned off instead?
Where mould is inside the silicone rather than on it, cleaning won’t reach it. Replacing the sealant is the lasting fix.
How long before a resealed shower can be used?
That varies with the product and the room conditions. Every area comes back to you with the time it needs before it gets wet.
Can some toilets stay open while you work?
Yes. We phase the work so some facilities stay in use on each floor or wing.
Can you work on healthcare sites?
Yes, within the site’s infection-control rules and permit systems. Tell us the requirements when you send details.
Do you replace tiles or fittings?
No. Our work is the sealant. If a leak comes from a cracked tray, a failed waste or loose fittings, we’ll tell you.
Do you give a fixed price before you start?
Yes. Send photos, drawings or a joint schedule, or we can visit, and we’ll give you a fixed quote with the scope in writing before any work starts.
Are you accredited and insured?
Yes. We’re CHAS accredited and a Constructionline member, our applicators hold CSCS cards, and we carry £5m public liability insurance.
Page updated 3 November 2026
Near you
Find commercial washroom and wet-area sealing in your town:
- London
- Glasgow
- Edinburgh
- Aberdeen
- Dundee
- Southampton
- Portsmouth
- Brighton
- Reading
- Oxford
- Guildford
- Chelmsford
- Maidstone
- Milton Keynes
- Watford
- Basildon
Advice
- Hotel Sealant Programmes: Room by Room
- Sealant Work in Hospitals and Care Homes
- Hygienic Sealing in Commercial Kitchens
- Planning Sealant Works in School Holidays
- Adhesive, Cohesive and Substrate Sealant Failure