Greater London · England
Brockley Remedial Sealant
Problem with your failed sealant joints in Brockley? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Dark patches showing through the sealant
- Sealant applied over old sealant that has lifted
- Gaps opening along the back of the worktop
Different surfaces, different methods
Movement & expansion joints
Bonding on three sides is a common reason movement joints tear. Backing stops that, letting the sealant flex between the two faces.
Leaking trays & enclosures
If the tray is cracked, or the leak is from the valve or waste, sealant won’t fix it. We’ll tell you what we find.
How we handle remedial sealant in Brockley
With more than 20 years’ experience, our applicators have seen most of the ways sealant can fail. We are fully insured ARBOMaster approved applicators, and every remedial job comes with a 12-month guarantee. Common call-outs are for a shower that leaks however often it’s resealed and movement joints that have split or pulled away, across shrunken worktop sealant, leaking tray & enclosure joints and failed movement joints.
Much of London’s older housing is Victorian and Edwardian terraces, many of them now split into flats, with bathrooms fitted into whatever space was available. A compact bathroom that steams up every day is hard on silicone and grout.
You’re covered for a year from the day we finish. If there’s a problem with it, please phone 0345 464 0079 or email us.
- Location
- Brockley (SE4, SE23, SE6)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
When to call us in Brockley
Even good sealant ages. Over the years it shrinks, hardens and gets colonised by mould, faster where ventilation is poor. At that point it has to come out.
It’s worth asking for a quote if you see:
- Sealant that came away because the surface wasn’t prepared
- Black mould underneath the bead
- Worktop sealant that has shrunk and split
- Repeat leaks from the same joint
If you look after a building such as Beecroft Garden Primary, 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.
Comparing quotes
- How much experience the applicator has
- Are they insured?
- What happens if they find a problem under the old sealant
- What the quote includes, VAT included or not
Quotes for remedial sealant in Brockley
Call for a quick quote. What matters most is:
- Access and height
- The type of sealant required
- Working hours on commercial sites
- Mould in or behind the old joints
A few things move the cost up or down: the old material and how easily it comes out, whether mould needs treating, and whether the work is at height. We take all of that into account in your quote.
What to tell us for a quote
To help us quote quickly, let us know:
- Where the job is, and your postcode
- Pictures of the joints, sent by email
- Access, such as stairs, a lift or height
- The problem you’ve noticed
Want a quote for remedial sealant? Please phone 0345 464 0079 or send us an email with a few details. We’ll explain what we’d do and give you a clear price before we start.
Should I try it myself first?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and does not move well, and the joint depth matters as much as the finish.
If you’re set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
What we do, step by step
There is not much for you to do on the day. Show us the job and we’ll take it from there. The work itself takes a few hours for most joints, depending on how much old sealant has to come out. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. Mention any building rules, key holders or managing agents when you book.
- We start by checking the joint for movement, leaks and the reason it failed.
- We strip the joint completely, removing any layers below.
- The joint is cleaned, treated for mould and left to dry.
- Where the joint moves, backing and a flexible sealant suited to the movement go in.
- Finally we finish the joint and talk you through what we found.
Before we arrive
- Move anything stored near the joints
- Keep pets and children clear of the area while we work
- Mention any parking rules near the property
Ask for a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints, and email pictures if that’s easy.
Related advice
FAQs for Brockley
Can you help a landlord with a rental near Crofton Park station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. You can phone 0345 464 0079 or email us with the details for a clear quote.
Could a tired shower seal in my Brockley flat affect the neighbours below?
Yes. In a flat, water from a failed bath or shower seal has only one way to go, and that’s down. Cutting out the old sealant and laying a new bead early stops it getting that far.
Do you remove the old sealant?
Yes, always, and completely. New sealant will not bond properly to old, so the joint is cleaned back first.
Where do you work from?
We are based in Crawley, West Sussex, and we work across South East England, London and Scotland.
Do you come to Brockley?
Yes. We’re based in Crawley and work across South East England, London and Scotland, Brockley included.
How long does remedial resealing take?
A little longer than a standard reseal. Most jobs take a few hours, and we confirm the time with your quote.
Are you fully insured?
Yes. We are fully insured, and we have been doing sealant work for more than 20 years.
Do I need to be at home?
Access is agreed with you when the job is booked. Indoors, that generally means someone at home.
Keeping the joints in good condition
Looking after new joints is easy:
- Look for stains below bathrooms now and then
- Report a tray that rocks or a worktop that lifts
- Never seal over old silicone
- Clean sealant with mild products only
Clean gently: no scraping, scouring pads or harsh chemicals.
Leaks through failed sealant grow over time. Each use pushes more water behind the bead, into floors, walls or ceilings. Sorting it early limits the damage.
Towns and villages near Brockley
Other services in Brockley
What happens if it’s left?
Ripping out a bathroom isn’t generally needed. When the fittings are sound, stripping and resealing the joints is often enough. Where something else has failed, you will hear it from us. In London conversions, one flat’s bathroom is often above another flat’s ceiling, and a slow leak from a failed seal can end up in the flat below. Dealing with it early is far simpler.
Doing several joints on one visit is generally more efficient than separate visits, so tell us about everything that needs sealing. You will get one clear quote for the whole job.
Why choose Mr Mastic in Brockley
- Rated 4.9 stars on Google
- We never seal over old sealant
- White, clear, grey or coloured to suit, where the product allows
- Tidy, careful work
Read what affects the cost or customer reviews.
Remedial sealant in Brockley: local notes
London has a lot of flats and conversions, and a failed shower or bath seal in one can show up on the ceiling below, so tired sealant is best dealt with early. London has hard water, so limescale builds up on sealant, grout and fittings.
If you let a flat or house near Crofton Park station, a joint that keeps failing is best fixed properly while the property is empty. Homes close to Church of St Hilda include some older properties, and bathrooms in older houses have often been refitted more than once, with sealant laid over sealant.
Brockley is about 1 mile south of New Cross, in Greater London. If you need remedial sealant in Brockley, please phone 0345 464 0079 or send us an email for a quick quote. We’re based in Crawley and cover Greater London, Brockley included. 764 places in Greater London are on our list.
Our applicators cover all of the SE4, SE23 and SE6 postcode area for remedial sealant and the streets around it. If you need remedial sealant at a property on Ivy Road, Nash Road and Lindal Road or a nearby road, we can help. If you’re just outside Brockley, we cover Crofton Park (1 mile south-east), Honor Oak (1 mile west), Ladywell (1 mile east), Forest Hill (1 mile south-west) and Nunhead (1 mile north-west). Further out, we also cover London (4 miles north-west), City of Westminster (7 miles north-west), Marylebone (7 miles north-west), Kensington (8 miles north-west), St Pancras (6 miles north-west) and Shoreditch (5 miles north).
Near you in Brockley
In Brockley, that means homes and buildings near Blythe Hill Tavern, Allenby Tutorial Trust and Blythe Hill Fields, among other places. Brockley has its own railway station: Crofton Park station. A little further out are Horniman Museum and Gardens (1.4 miles south-west) and University Hospital Lewisham (0.7 miles east). Green spaces nearby include One Tree Hill and Knight's Hill.