Greater London · England
Remedial sealant & repairs in Sanderstead, Greater London
Professional remedial sealant in and around Sanderstead, with old sealant always removed completely.
- Gaps opening along the back of the worktop
- Sealant applied over old sealant that has lifted
- Sealant that came away because the surface wasn’t prepared
Remedial sealant in Sanderstead
In Sanderstead, as anywhere, remedial jobs tend to look alike: over-sealed joints, hidden mould, repeat leaks and split movement joints. Each is stripped back and done again properly. We work on botched or over-sealed joints, failed movement joints and mouldy bath & shower sealant, and common reasons people get in touch are sealant applied over old sealant that has lifted and worktop sealant that has shrunk and split.
In much of London, period terraces have been converted into flats over the years, with bathrooms fitted into whatever space was available. A compact bathroom that steams up every day is hard on silicone and grout, and homes in Sanderstead are no different.
You’re covered for a year from the day we finish. If there’s a problem with it, please phone 0345 464 0079 or send us an email.
- Place
- Sanderstead (CR2, CR8)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
What affects the cost of remedial sealant
There’s no set price list, because no two jobs are the same. The quote depends on:
- Any mould that needs treating
- The size of the job
- Whether old sealant or filler has to be cut out
- Which sealant suits the joint
Commercial jobs are quoted on the same basis as homes: how much there is to do, how we reach it and what it needs. Ask us for a quote and we will go through it with you.
What we need to know
To make quoting easier, let us know:
- The problem you’ve noticed
- Photos by email, if that’s easy
- Access, such as stairs, a lift or height
- Any previous sealing or DIY work
There’s no standard price list, because every job is different. Instead, your job gets its own clear quote. To get started, ring 0345 464 0079 or send us an email.
Also near Sanderstead
Also in Sanderstead
What happens on the day
Most of a good job is in the preparation, and we do not rush it. Every joint is cleaned and dried before new material goes in. All told, the work takes a few hours for most joints, depending on how much old sealant has to come out. In a London area like Sanderstead, the main things to plan are parking and access: let us know about parking, the floor we’ll be working on and any lift or shared entrance.
- 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.
Before we arrive
- Mention any tricky access
- Mention any parking rules near the property
- Let us know if you’ve seen damp or leaks
How to get a quote
Asking for a quote is easy: let us know the job and the location. Photos by email help us understand the job, and we’ll take it from there.
Related advice
Honest limits
Sealant is not the answer to every problem, and we’d rather say so up front. It will not solve:
- Older mastics that may need an asbestos check before removal
- A tray or bath that’s cracked
- Plumbing leaks behind walls or under trays
Not sure which it is? You can phone 0345 464 0079 or drop us an email and we will tell you honestly before booking.
Joints and surfaces we work on
- Botched or over-sealed joints
- Failed movement joints
- Mouldy bath & shower sealant
- Shrunken worktop sealant
- Expansion joints
- Leaking tray & enclosure joints
What the job involves on each surface
Over-sealed & botched joints
A thick bead smeared across tiles often hides mould or gaps. Taking it back shows what’s underneath, then reseal neatly.
Leaking trays & enclosures
If the tray is cracked, or the leak is from the valve or waste, sealant will not fix it. We say so rather than reseal.
Common problems we fix in Sanderstead
How a joint is built matters as much as the product. Sealant packed too deep, or stuck to the back of the joint as well as the sides, cannot stretch, so it tears when the joint moves. Backing rod or bond-breaker tape prevents it.
It’s worth asking for a quote if you see:
- Wide, uneven beads that look worse than the old ones
- Over-sealed joints coming away
- Movement joints that have split or pulled away
- Sealant peeling off a dusty or damp surface
Rented homes near Riddlesdown station change hands often, and botched sealant from a previous quick fix is easier to strip out between tenants.
What to look for in a quote
- Whether they seal over old material or remove it
- Which colour the sealant will be
- Who turns up on the day
- What insurance they hold
Sanderstead questions
Do you work for landlords with property near Riddlesdown station?
Yes, we work for letting agents and landlords. You can phone 0345 464 0079 or email us with the address and a few details, and we’ll give you a fixed price before we start.
Can worn sealant in a flat in Sanderstead cause a leak downstairs?
Yes, it can. Water that gets past failed sealant or cracked grout can run under the bath or tray and show up on the ceiling below. It’s far simpler to replace tired sealant early than to deal with a neighbour’s ceiling.
Are you an approved applicator?
Yes. We’re an ARBOMaster approved applicator.
Where are you based?
Mr Mastic is based in Crawley. Our applicators cover Sanderstead, along with the rest of our area.
Do you take out the old sealant first?
Always. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Can you fix a reseal that hasn’t worked?
Yes. There’s usually a reason: sealant over sealant, movement or another leak, and we deal with the cause first.
Can you remove sealant that’s been put over old sealant?
Yes. Both layers come out; new silicone doesn’t bond to old silicone, which is why over-sealing fails.
Will there be a smell?
That depends on the sealant. Some products have a noticeable smell, others very little.
Remedial sealant in Sanderstead: local notes
London has hard water, so limescale builds up on sealant, grout and fittings, and it has to be cleaned off before new sealant goes in. London has a lot of flats and conversions, and a failed shower or bath seal in one can show up on the ceiling below, which is why it’s worth fixing early.
Sanderstead is in London, so parking needs planning: let us know about parking bays, permits or a driveway. If you look after a building such as Gresham Primary School, its toilets, changing areas and kitchens need their sealant renewed like any other building’s.
Sanderstead is about 2 miles east of Purley, in Greater London. Jobs in Sanderstead get the same care as everywhere else we work: old sealant removed completely, careful preparation and a 12-month guarantee. 764 places in Greater London are on our list, large and small. London is on our list too, around 11 miles away.
Postcode districts we cover here for remedial sealant: CR2 and CR8. Local streets include Hyde Road, Brian Avenue and Sundown Avenue. With the A2022 close by, Sanderstead is simple for us to get to for remedial sealant. If you’re just outside Sanderstead, we cover Riddlesdown (1 mile south-west), Kenley (1 mile south-west), South Croydon (1 mile north-west), Selsdon (1 mile north-east) and Hamsey Green (1 mile south-east). We also work in nearby towns such as London (11 miles north), City of Westminster (13 miles north), Marylebone (13 miles north), Kensington (12 miles north-west), St Pancras (13 miles north) and Shoreditch (13 miles north).
Landmarks near Sanderstead
In Sanderstead, that means homes and buildings near Selsdon Park Hotel, Littleheath Woods and Riddlesdown Collegiate, among other places. Sanderstead’s nearest station is Riddlesdown station, about 0.8 miles west. Other landmarks nearby include Purley War Memorial Hospital (1.4 miles west) and Croydon Airport Visitor Centre (2.1 miles north-west). The countryside around Sanderstead includes Duppas Hill and Foxley Wood.
Leave it or put it right?
Adding more sealant is the usual quick fix, and it rarely works. It cannot bond to what’s underneath, leaving the leak in place and one more layer to cut out later. In a flat in Sanderstead, failed sealant seldom stays inside your own four walls: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
There are no prices on our website, because the cost depends so much on the job itself. Call for a quick quote.
Why book with us
- 180+ five-star Google reviews
- Full insurance on every job
- ARBOMaster approved applicator
- Experience in homes, commercial sites and hotels
DIY versus a professional finish
The difference is mostly in the preparation and the product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions.
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.