Greater London · England
Roundshaw Remedial Sealant
Removing failed, mouldy or leaking sealant and putting it right for Roundshaw, backed by a 12-month guarantee. Call for a quick quote.
- A second bead peeling off the first
- Leaks that keep coming back after resealing
- Products that weren’t meant for the joint
When something else is needed
Some problems need a builder, plumber or other trade rather than us:
- Failed tanking or loose tiles behind the sealant
- Movement from fittings that are not supported
- Sealant in an older building that needs testing for asbestos first
If in doubt, phone 0345 464 0079 or email us and we’ll say what we think.
Surfaces we seal
- Failed movement joints
- Mouldy bath & shower sealant
- Botched or over-sealed joints
- Expansion joints
- Leaking tray & enclosure joints
- Shrunken worktop sealant
About our remedial sealant in Roundshaw
Getting old sealant out properly is slow, careful work. Every layer is cut out, the residue cleaned off and the joint degreased, without scratching tiles, trays or frames. Only then can new sealant bond. Typical jobs include sealant peeling off a dusty or damp surface and a shower that leaks however often it’s resealed, across shrunken worktop sealant, mouldy bath & shower sealant and expansion joints.
Much of London’s older housing is Victorian and Edwardian terraces, many of them now split into flats, and bathrooms were often squeezed into small rooms. Small, steamy rooms are where mould gets into sealant and grout fastest, and homes in Roundshaw are no different.
All of our work is guaranteed for twelve months.
- Place
- Roundshaw (SM6, CR8, CR0)
- Wider area
- Greater London
- Cover
- One year on every job
- Quotes
- A clear price before we start
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
How it works
A visit follows a simple pattern: we check the joints, mask and protect the surrounding surfaces, do the work and clear up. It generally takes a few hours for most joints, depending on how much old sealant has to come out. In Roundshaw, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- Surrounding tiles, trays and frames are protected first.
- Every layer of failed sealant is stripped out.
- We clean and degrease the joint and look for signs of movement or water.
- New sealant goes in once the joint is dry, and is tooled smooth.
- You get the cure time and our view on why the joint failed.
How to prepare
- Mention any leaks or damp you’ve noticed
- For indoor joints, keep the area dry beforehand if you can
- Tell us about any previous sealing or DIY attempts
How to get a quote
Asking for a quote is easy: tell us what needs doing and where. Photos by email help us understand the job.
Read more
Nearby places to Roundshaw
Other services in Roundshaw
Leave it or put it right?
Remedial work takes longer than a straight reseal, but not by much: it takes a few hours for most joints, depending on how much old sealant has to come out. It’s far less disruption than resealing the same joint again and again. Converted houses in London often have a bathroom above someone else’s living room, so a small leak from tired sealant can mean a neighbour’s ceiling and a lot of disruption. Dealing with it early is far simpler for homes in Roundshaw.
No two jobs are quite the same, so each one gets its own quote. Size, access and the product the joint needs all make a difference.
Why choose Mr Mastic in Roundshaw
- We agree the colour with you first
- Full insurance on every job
- Every job guaranteed for a year
- Approved under the ARBOMaster scheme
Take a look at what affects the cost or our reviews.
Work for landlords, hotels and businesses
Mouldy or split sealant often shows up at the end of a tenancy, and it’s quick to put right between tenancies. Several properties can go on one quote.
We also work for property managers and facilities teams in Roundshaw and across Greater London. Several sites can be quoted together, and we are fully insured.
Roundshaw questions
Do you work for landlords with property near Wallington station?
Yes, we work for landlords and agents. Just call 0345 464 0079 or send us an email and tell us about the property, and we will send you a clear quote.
Is parking a problem for a job in Roundshaw?
Parking in Roundshaw, as in most of London, takes a little planning: a visitor permit or a bay close to the door helps a lot.
What if the leak isn’t the sealant?
We check for that before we reseal. If the fault is elsewhere, you’ll know before any work is done.
What does remedial sealant cost?
Every job is different, so each one gets its own quote. For a quick quote, call 0345 464 0079 or send us an email with a short description of the job.
Do you work for hotels and businesses?
Yes, regularly. We can plan bigger jobs in stages.
How long will it take to strip and reseal the joint?
That depends on how many layers there are and how many joints. You’ll have a timescale before any work begins.
Is there any odour?
That depends on the sealant. Some smell for a while, some hardly at all.
Can I add another job to the visit?
Yes. Tell us about everything you’d like done.
Aftercare tips
How long the joints last depends on use and care. We suggest:
- Clean sealant with mild products only
- Ask why a joint failed before redoing it
- Keep movement joints clear of mortar and paint
- Act on a lifting corner right away
If the joint ever needs renewing, have it cut out, not sealed over. Over-sealing is how many remedial jobs start.
A failing joint rarely gets better on its own. Every shower or downpour sends more water through, into floors, walls or ceilings. Sorting it early limits the damage.
What we are called out for in Roundshaw
Silicone only bonds to surfaces that are clean and dry. Residue, moisture or dust left in the joint weaken the bond, so it starts lifting sooner than it should.
The problems people usually mention when they call include:
- A second bead peeling off the first
- Movement joints that have split or pulled away
- Kitchen joints letting water behind the worktop
- Dark patches showing through the sealant
Letting a property close to Wallington station? Then botched sealant from a previous quick fix is easier to strip out between tenants.
Comparing quotes
- What guarantee comes with the work
- Is the old sealant removed completely?
- What happens if they find a problem under the old sealant
- How the colour is chosen
Remedial sealant in Roundshaw: local notes
There are hotels and other places to stay in and around Roundshaw. As well as homes, we work in hotel bathrooms, where resealing and regrouting can be done room by room. London’s water is hard, so limescale builds up on sealant, grout and fittings, and it has to be cleaned off before new sealant goes in.
Managing a site like Wallington Primary Academy? Then washroom and kitchen sealant there needs the same care as at home, and schools and businesses are part of our work as well as homes. In the older streets around St. Paul's, timber floors under older bathrooms flex, so joints need a sealant that moves with them.
Roundshaw is about 2 miles south-west of Croydon, in Greater London. For remedial sealant in and around Roundshaw, it’s easy to get a quote: please call 0345 464 0079 or send us an email. We are based in Crawley and cover Greater London, Roundshaw included. Roundshaw is one of 764 towns and villages in Greater London we cover. We also work in London, about 10 miles from Roundshaw.
Every address in SM6, CR8 and CR0 is within our area for remedial sealant. That includes homes and businesses on Link Lane, Milton Road and Redwing Road. If you’re just outside Roundshaw, we cover Russell Hill (1 mile east), Bandonhill (1 mile north), Peaks Hill (1 mile south), Waddon (1 mile north-east) and Wallington (1 mile north-west). Within a short drive, we also cover London (10 miles north), City of Westminster (11 miles north), Marylebone (11 miles north), Kensington (11 miles north), St Pancras (12 miles north) and Shoreditch (12 miles north).
Near you in Roundshaw
Locally, jobs take us to homes and businesses close to Wilson's School, Waddon Ponds and The John Fisher School. Roundshaw’s nearest station is Wallington station, roughly 0.9 miles north-west of the centre. Well-known places in the area include Purley War Memorial Hospital (1.2 miles south-east) and Croydon Airport Visitor Centre (0.6 miles east). Green spaces nearby include Roundshaw Downs and Duppas Hill.
Can I do it myself?
Sealing over old silicone is the commonest DIY error. Silicone doesn’t stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
A DIY attempt doesn’t rule out a professional job. We cut it out and start again, so tell us about it when you ask for a quote.