Greater London · England
Dulwich Remedial Sealant
Remedial sealant for Dulwich and the surrounding area: careful preparation, the right product and tidy work. Ask us for a quick quote.
- A second bead peeling off the first
- Movement joints that have split or pulled away
- Leaks that keep coming back after resealing
The process
Good joint work is mostly preparation, so that’s where we spend the time. Joints are cleaned back and dried before anything new goes in. In total, it generally takes a few hours, depending on how many layers have to come out. In a London area like Dulwich, 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 start by checking the joint for movement, leaks and the reason it failed.
- We strip the joint completely, removing any layers below.
- Next, any mould is treated and the joint dried.
- Where the joint moves, backing and a flexible sealant suited to the movement go in.
- The new joint is tooled neatly and we explain anything else we found.
Before we arrive
- Clear items away from the joints we are working on
- Mention any tricky access
- Mention any parking rules near the property
Getting a quote
Asking for a quote is easy: let us know the job and the location, and roughly how big it is. A few photos by email make the job easier to understand, and we’ll come back to you with a quote.
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Remedial sealant in Dulwich, done properly
Remedial jobs in Dulwich normally fall into a few patterns: sealant over sealant, mould under the bead, leaks that come back and movement joints that have split. Each is stripped back and done again properly. If you have floor or wall movement joints that have failed and sealant that came away because the surface wasn’t prepared, we can help, whatever the surface.
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.
Whatever the size of the job, you get the same one-year guarantee in Dulwich and across Greater London.
- Location
- Dulwich (SE22, SE21, SE23)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quote
- A clear price before work begins
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
What affects the cost of remedial sealant
You’ll get a clear quote before any work starts. It takes into account:
- The number and length of the joints
- Any mould that needs treating
- The old material and how stubborn it is
- The type of sealant required
Homes and businesses are quoted the same way: the amount of work, the access and the products needed. Ask us for a quote and we’ll explain what it covers.
What we need to know
A few details help us give you an accurate quote. When you ask for a quote, tell us:
- Any previous sealing or DIY work
- What’s wrong with the joints now
- Pictures of the joints, sent by email
- Any access issues, like height or stairs
To get a quote, call 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.
Honest limits
Sealant isn’t the answer to every problem, and we’ll tell you before we start. It will not solve:
- Plumbing leaks behind walls or under trays
- Older mastics that may need an asbestos check before removal
- A tray or bath that is cracked
Not sure which it is? You can call 0345 464 0079 or send us an email and we will tell you honestly.
Surfaces we seal
- Botched or over-sealed joints
- Failed movement joints
- Shrunken worktop sealant
- Mouldy bath & shower sealant
- Expansion joints
- Leaking tray & enclosure joints
Why deal with it now?
Leaks that are left keep doing damage out of sight: wet floors, stained ceilings and swollen worktops. Dealing with the joint now is a small job by comparison. In older London homes, water behind a failed joint soaks into brick and timber without much sign, and once it shows in Dulwich, the repair is bigger than a sealant job.
No two jobs are quite the same, so we quote each one individually. Size, access and the product the joint needs all play a part, and we will explain the quote if you ask.
Why choose Mr Mastic in Dulwich
- 180+ five-star Google reviews
- One-year guarantee on every job
- ARBOMaster approved applicator
- Trusted Arbo and Everbuild sealants
See our cost guide or our reviews.
What the job involves on each surface
Mouldy bath & shower sealant
Black mould inside the bead won’t scrub out. All of it comes out, and the joint is treated and dried ahead of a new anti-fungal bead.
Windows & doors
Wrong-coloured or messy mastic can be replaced for appearance too, matched to the frame colour.
Landlords, agents and businesses in Dulwich
For anyone letting property in or around Dulwich, jobs at different addresses can be quoted together. Send us the addresses and the work at each.
We also work for property managers and facilities teams. We can quote a run of properties together.
FAQs for Dulwich
Do you work for landlords with property near West Dulwich station?
Yes, we work for landlords and agents. Just phone 0345 464 0079 or send us an email and tell us about the property, and we will send you a clear quote.
Do you take on hotel work around Dulwich?
Yes, hospitality work, including hotels, is part of what we do. Jobs can be programmed room by room, with out-of-hours working possible to arrange.
Will you leave a mess?
No. The area is protected while we work and cleaned up afterwards.
Will the old sealant be removed?
Yes, every time. New sealant won’t bond properly to old, so any old material comes out before anything new goes in.
Are you fully insured?
Yes, we’re fully insured for domestic and commercial work.
Is there any odour?
That depends on the sealant. Some smell for a while, some hardly at all.
Where is Mr Mastic based?
We work from Crawley. Our applicators cover Dulwich.
Can failed expansion joints be resealed?
Yes. If a joint has been filled with mortar or rigid filler, we rake it out where possible, and reseal with a flexible product.
What we are called out for in Dulwich
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 sets the depth and stops that.
Keep an eye out for any of the following:
- A second bead peeling off the first
- Wide, uneven beads that look worse than the old ones
- Torn expansion joints
- Sealant peeling off a dusty or damp surface
For landlords with property near West Dulwich station, a joint that keeps failing is best fixed properly while the property is empty.
Comparing quotes
- How the surfaces are prepared before sealing
- When the joint can take water or movement
- Is the old sealant removed completely?
- Which sealant they’ll use, and why
Remedial sealant in Dulwich: 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, which is why it’s worth fixing early. There are hotels and other places to stay in and around Dulwich. As well as homes, we work in hotel bathrooms, where resealing and regrouting can be done room by room.
For an older house near a landmark such as Christ's Chapel of God's Gift, timber floors under older bathrooms flex, so joints need a sealant that moves with them. If you look after a building such as St Anthony's Catholic Primary School, we reseal washrooms and kitchens in schools and businesses as well as homes.
Dulwich is about 1 mile south-east of Herne Hill, in Greater London. Our applicators cover remedial sealant for homeowners, landlords and businesses in Dulwich and the surrounding area. Across Greater London, we cover 764 places, Dulwich among them.
All of SE22, SE21 and SE23 is within our area for remedial sealant. Local streets include Court Lane, Druce Road and Boxall Road, all of which we cover. You’ll find Dulwich on the A2216, so it’s easy for us to get to with everything needed for remedial sealant. We also cover the places around Dulwich: Dulwich Village (1 mile north-west), West Dulwich (1 mile south), Herne Hill (1 mile north-west), Sydenham Hill (1 mile south-east) and Forest Hill (1 mile east). Within a short drive, we also cover London (4 miles north), City of Westminster (6 miles north-west), Marylebone (6 miles north-west), Kensington (7 miles north-west), St Pancras (6 miles north) and Shoreditch (6 miles north).
What’s near Dulwich
Around Dulwich, our work takes us to homes and buildings near The Crown and Greyhound pub, Dulwich Park and Alleyn's School, among other places. The nearest railway station is West Dulwich station, roughly 0.7 miles south-west. Nearby you will also find Dulwich Community Hospital (0.9 miles north) and Greenwich Castle (4 miles north-east). Open spaces near Dulwich include Knight's Hill and Centre for Wildlife Gardening.