Greater London · England
Knightsbridge Commercial Sealant
Commercial sealant across Knightsbridge and nearby, with old sealant always removed completely and a 12-month guarantee.
- Leaks from showers into rooms or ceilings below
- Split sealant around staff kitchen worktops and sinks
- Joints that need doing before an inspection or audit
Commercial sealant in Knightsbridge, done properly
Mr Mastic brings more than 20 years’ experience to commercial sites, and we are fully insured and ARBOMaster approved. If your site needs RAMS or insurance details, tell us, and we will confirm what we can supply with the quote. We work on welfare facilities, hotel bathrooms and rental portfolios, and common reasons people get in touch are shower leaks reaching the floor below and whole floors of tired en suites.
Commercial work in London comes with its own logistics: loading restrictions, building rules and tight access. Timings and access are agreed with the building before work starts in Knightsbridge.
The work is guaranteed for twelve months. If there’s a problem with our work within the year, let us know and we will sort it.
- Place
- Knightsbridge (SW1X, SW3, W1K)
- Region
- Greater London
- Guarantee
- 12 months on all our work
- Quote
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Can I do it myself?
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
A DIY attempt doesn’t rule out a professional job. We remove it and do the joint properly, so tell us about it when you ask for a quote.
Knightsbridge questions
I let a flat near London Victoria station. Can you help?
Yes. We work for letting agents and landlords as well as homeowners. You can call 0345 464 0079 or send us an email with the details for a clear quote.
Can parking be tricky for a visit in Knightsbridge?
Parking in Knightsbridge, as in most of London, takes a little planning: a visitor permit or a bay close to the door helps a lot.
Where is Mr Mastic based?
We are a Crawley-based firm, with over 20 years’ experience. Our area covers South East England, London and Scotland.
Do you take out the old sealant first?
Yes, every time. New sealant will not bond properly to old, so any old material comes out before anything new goes in.
Is it worth trying it myself?
That depends on the joint. High-level, external movement and fire-rated joints are professional jobs, while a short indoor joint may be within reach.
What do you put in the joint?
Quality sealants from brands including Arbo and Everbuild, picked for each joint. We’ll tell you what we are using and why.
Is out-of-hours working possible?
That can be arranged for many jobs. The hours are agreed before work starts.
How long do rooms need to be out of use?
Usually after around 24 hours. Each room is handed back with the cure time for the product used.
What happens on the day
Good joint work is mostly preparation, and we don’t rush it. Every joint is cleaned and dried before new material goes in. In total, it generally takes anything from a few hours to several days, depending on the number of rooms. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- We start by looking at the rooms and agreeing what’s needed.
- We agree when we’ll work, with early or out-of-hours slots where they can be arranged.
- Areas are protected and the failed sealant removed.
- Joints are dried, then resealed and tooled neatly.
- Housekeeping or site staff are told when each area can be used.
Getting ready for the visit
- Let us know about earlier repairs to the joints
- Let us know if you’ve seen damp or leaks
- Keep pets and children clear of the area while we work
How to get a quote
Getting a quote is simple: let us know what needs doing and where. Photos by email help us understand the job, and we will come back to you with a quote.
Related advice
Common problems we fix in Knightsbridge
Quick fixes come back quickly. Sealing over old silicone, sealing wet joints or using the wrong product means the joint fails again soon.
People usually contact us after spotting something like this:
- Failed joints in office kitchens and tea points
- Repeated reseals that don’t last
- Tired sealant ahead of a health and safety audit
- Shower leaks reaching the floor below
As a London address, Knightsbridge can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Questions to ask before you book
- Whether they’re fully insured
- When the joint can take water or movement
- Whether all the old sealant comes out first
- Whether VAT is included
Commercial sealant around Knightsbridge
There are hotels and other places to stay in and around Knightsbridge. Hotel work can be planned room by room, with out-of-hours working where needed. London’s water is hard, which leaves limescale on sealant, grout and taps.
Community buildings like Deutsche Evangelische Christuskirche are part of the picture too: halls and community kitchens see heavy use, and their sealant shows it. For landlords with property near London Victoria station, several rental properties can be resealed on one programme.
Knightsbridge is about 1 mile north of Brompton, in Greater London. If you need commercial sealant in Knightsbridge, please ring 0345 464 0079 or drop us an email for a quick quote. We’re based in Crawley and cover Greater London, Knightsbridge included. Our Greater London coverage runs to 764 places, Knightsbridge among them.
All of SW1X, SW3 and W1K is within our area for commercial sealant. If you need commercial sealant at a property on Hans Road, Park Lane and Cadogan Lane or a nearby road, our applicators can take on the job. Knightsbridge is on the A315 and A4202, which makes it straightforward to reach with everything needed for commercial sealant. Other places close to Knightsbridge include Tyburn (1 mile north), Mayfair (1 mile north-east), Hyde Park Estate (1 mile north), Connaught Village (1 mile north) and City of Westminster (1 mile north-east). Larger places within reach include London (3 miles east), St Pancras (3 miles north-east), Shoreditch (4 miles north-east), Walthamstow (8 miles north-east), Hoxton (4 miles north-east) and Whitechapel (4 miles east).
Around Knightsbridge
Locally, jobs take us to homes and businesses close to Saint Thomas More Language College, St Joseph's Catholic Primary School and Paxtons Head pub, among other places. You will also find Natural History Museum Library and Archives (0.7 miles south-west) and Royal Parks of London (0.5 miles north). The nearest railway station is London Victoria station, about 0.9 miles south-east of the centre. A little further out are London Lock Hospital (0.6 miles east) and Westminster Synagogue Czech Memorial Scrolls Museum (within half a mile west). The countryside around Knightsbridge includes Campden Hill and Greville Place nature reserve.
Surface by surface
Student & care accommodation
Halls and care homes often have many near-identical bathrooms. A room-by-room programme keeps the job efficient.
Office washrooms & kitchens
Office washrooms and tea points are used all day, so the work can be arranged for quieter times. We reseal around basins, urinals, worktops and sinks.
What affects the quote in Knightsbridge
Your quote is based on your job. We look at:
- How much old sealant there is and how hard it is to remove
- How many rooms, windows or areas are involved
- Working hours on commercial sites
- The number and length of the joints
What it costs depends on how much there is to do, how much old material has to come out and access to the work. You’ll have a clear quote before any work starts.
What we need to know
To help us quote quickly, please include:
- The type of property
- The address or postcode of the job
- Photos by email, if that’s easy
- Whether it has been sealed before
Quotes start with a quick conversation. Describe the problem, the location and the size of the job, and we’ll talk you through what we’d do. Whenever you’re ready, phone 0345 464 0079 or email us.
Also near Knightsbridge
Also in Knightsbridge
Aftercare tips
Aftercare is simple, and it makes a real difference:
- Ask cleaners to go gently on the silicone
- Keep extractor fans working and serviced
- Leave squeegees in busy showers
- Keep a record of which rooms were resealed and when
Strong chemicals and scourers wear silicone out faster. A mild cleaner and a soft cloth is enough for the joints.
Black sealant in a staff washroom or guest bathroom draws complaints. Left long enough, it spreads through the bead, and only replacement fixes it.
What sealant work can’t fix
We’d rather tell you now than do work that will not last, so these are the limits:
- Leaking pipework, valves or wastes (a plumber’s job)
- Extraction that is not working, which needs an electrician or ventilation contractor
- A shower tray, bath or basin that’s cracked or broken
If in doubt, ring 0345 464 0079 or email us and we will say what we think.
Where we work in Knightsbridge
- Office washrooms & kitchens
- Rental portfolios
- Student & care accommodation
- Welfare facilities
- Hotel bathrooms
- Retail & leisure sites