Greater London · England
Sydenham Hill Remedial Sealant
Failed sealant joints in Sydenham Hill need attention? We remove the old material, prepare the joints and seal them properly, with a one-year guarantee.
- Leaks that keep coming back after resealing
- Worktop sealant that has shrunk and split
- Sealant peeling off a dusty or damp surface
Remedial sealant for homes and businesses in Sydenham Hill
Decorators’ caulk in a shower, bathroom silicone on a window, a rigid filler in a movement joint won’t last, however tidy it looks. We take it out and use a sealant made for that joint. If you are dealing with sealant peeling off a dusty or damp surface and leaks that keep coming back after resealing, we can put it right, on leaking tray & enclosure joints, failed movement joints and mouldy bath & shower sealant alike.
Hard London water leaves limescale on sealant, grout and taps alike. For a bathroom or kitchen in Sydenham Hill, getting the joints right keeps water where it belongs and the room looking clean.
The work is guaranteed for twelve months. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Location
- Sydenham Hill (SE26, SE23, SE21)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Quotes
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
How to look after the new joints
To keep the joints looking good and working properly:
- Do not point over movement joints
- Do not wait for a small gap to become a leak
- Find out why the sealant failed first
- Never seal over old silicone
If the joint ever needs renewing, have it cut out, not sealed over. New silicone does not bond to old, so the old bead should always come out first.
Signs to act on: peeling layers, mould showing through the bead, leaks after showering or cracks in a movement joint. Each one is worth getting looked at.
What we can’t put right
We’d rather tell you now than do work that won’t last, so these are the limits:
- A tray or worktop that needs refixing first
- Sealant in an older building that needs testing for asbestos first
- A cracked shower tray or bath (that needs repair or replacing)
If in doubt, phone 0345 464 0079 or send us an email and we will say what we think before booking.
Where we work in Sydenham Hill
- Expansion joints
- Leaking tray & enclosure joints
- Shrunken worktop sealant
- Failed movement joints
- Botched or over-sealed joints
- Mouldy bath & shower sealant
Towns and villages near Sydenham Hill
Also in Sydenham Hill
What happens on the day
Every visit runs the same way: we look at the joints together, protect the area around them, 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. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Sydenham Hill. A visitor permit or a nearby bay makes the visit run more smoothly.
- We protect the surfaces around the joint.
- The botched or failed sealant is cut away completely.
- 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.
- We give you the cure time and explain what caused the failure.
Preparing for the visit
- Plan for the work area to be out of bounds to pets and children
- Let us know about stairs, lifts or work at height
- For business premises, tell us about site rules or sign-in
How to get a quote
For a quote, phone 0345 464 0079 or email us and tell us where the job is and what the problem looks like. You will have a clear quote before work begins.
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What the job involves on each surface
Over-sealed & botched joints
Botched joints sometimes have damaged edges from earlier scraping. We take care not to make it worse, and point out any existing damage.
Leaking trays & enclosures
Where the joints are the problem, every bead is stripped and resealed with anti-fungal sanitary silicone, tray edges and screen profiles included.
Your questions about remedial sealant in Sydenham Hill
Can parking be tricky for a visit in Sydenham Hill?
Parking in Sydenham Hill, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
Do you work in hotels near Sydenham Hill?
Yes. Hotel and guest-house work is part of what we do. Jobs can be programmed room by room, with out-of-hours working possible to arrange.
Do the sealants smell?
Sometimes, a little. Any smell clears as the sealant cures.
Should I try DIY first?
It depends on the job. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional, while a short indoor joint may be within reach.
Do you have insurance?
Yes. We’re fully insured for domestic and commercial work.
Do you take out the old sealant first?
Yes. All of the old material is cut out and the joint cleaned before resealing.
How much does remedial sealant cost in Sydenham Hill?
The cost depends on the size of the job, access and how much old sealant has to come out. Ask us for a quote and we’ll talk you through it.
Can I add another job to the visit?
Yes, we can. Several rooms, windows or areas can go on one quote.
Work for landlords, hotels and businesses
Hotels need rooms back in use, so we plan the work room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
Mouldy or split sealant often shows up at the end of a tenancy. Several properties can be quoted together.
What happens if it’s left?
Stripping out botched sealant adds time to a reseal, but rarely a lot: it takes a few hours for a typical bath or shower, longer where several layers have been applied. It’s far less disruption than resealing the same joint again and again. In older London homes, water behind a failed joint soaks into brick and timber without much sign, and by the time it shows on a wall or ceiling in Sydenham Hill, the repair is bigger than the sealant job would have been.
Combining jobs into one visit is generally more efficient than separate visits, so tell us about everything that needs sealing. We’ll give you a clear price for the lot.
Why choose Mr Mastic in Sydenham Hill
- ARBOMaster approved applicator
- You choose the colour before work begins
- More than 20 years in sealant work
- Anti-fungal sanitary silicone in wet areas
See our cost guide or what customers say.
What we’re called out for in Sydenham Hill
Some joints fail because water is reaching them from behind. A leaking valve, a failed waste or cracked grout feeds water behind the bead, and the sealant lifts or goes mouldy from underneath.
It’s worth asking for a quote if you see:
- A shower that leaks however often it’s resealed
- Gaps opening along the back of the worktop
- Smears and lumps from a botched reseal
- Sealant applied over old sealant that has lifted
For an older house near a landmark such as Church of St Philip the Apostle, timber floors under older bathrooms flex, so joints need a sealant that moves with them.
What to look for in a quote
- What the cure time is
- Are they insured?
- What happens if they find a problem under the old sealant
- How much experience the applicator has
Bathrooms and kitchens in Sydenham Hill
London has hard water, which leaves limescale on sealant, grout and taps. There are hotels and other places to stay in and around Sydenham Hill. As well as homes, we work in hotel bathrooms, where resealing and regrouting can be done room by room.
Sydenham Hill is in London, so parking needs planning: let us know about parking bays, permits or a driveway. Letting a property close to Sydenham Hill station? Then failed or mouldy sealant is worth putting right between tenancies, before it turns into a leak.
Sydenham Hill is about 1 mile east of West Norwood, in Greater London. Whether you are in the middle of Sydenham Hill or further out, remedial sealant is available for homes and businesses alike. Our Greater London coverage runs to 764 places, and Sydenham Hill is one of them.
Postcode districts we cover here for remedial sealant: SE26, SE23 and SE21. If you need remedial sealant at a property on Grange Lane, Dallas Road and Lyall Avenue or a nearby road, we can help. Nearby, we also carry out remedial sealant in West Dulwich (1 mile west), Sydenham (1 mile south-east), Crystal Palace (1 mile south), Dulwich (1 mile north-west) and Gipsy Hill (1 mile south-west). Within a short drive, we also cover London (5 miles north), City of Westminster (7 miles north-west), Marylebone (7 miles north-west), Kensington (7 miles north-west), St Pancras (7 miles north) and Shoreditch (6 miles north).
What’s near Sydenham Hill
Typical jobs here are in homes near Long Meadow, The Wood House and Sydenham School and the streets around them. Sydenham Hill’s nearest station is Sydenham Hill station, roughly 0.5 miles west of the centre. Well-known places in the area include Horniman Museum and Gardens (0.6 miles north-east) and Lewisham Shopping Centre (3.2 miles north-east). Green spaces nearby include Knight's Hill and Dulwich Upper Wood.