Greater London · England
East Dulwich New Build Mastic
Plot mastic for developers and snagging failed sealant in new homes in East Dulwich, with a 12-month guarantee on every job. Ask us for a quote.
- Worktop and upstand sealant coming away
- Plot mastic for developers ahead of handover
- Cracked sealant around new window and door frames
New build mastic in East Dulwich
Some new-home owners let the house settle before resealing. That makes sense for small gaps that are just cosmetic, but a failed shower or bath seal shouldn’t wait. If you are dealing with joints pulling apart as timber shrinks and gaps behind new kitchen upstands, we can put it right, whatever the surface.
From brand-new flats to converted terraces with new flooring, London has every kind of floor. Every joint between floor, skirting and threshold has to cope with some movement, in East Dulwich as anywhere.
Big or small, it’s backed by our 12-month guarantee in East Dulwich and across Greater London.
- Place
- East Dulwich (SE5, SE22, SE15)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before work begins
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Can I do it myself?
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
How the visit works
Before we leave, we go over the finished joints with you and tell you how long to leave it. The visit itself generally takes a few hours in a single home, depending on the size of the job. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in East Dulwich. It helps if you can point us to a visitor permit or a bay close to the door.
- Each joint is checked for movement before we start.
- We remove the failed sealant and clean the joints.
- We make sure the joints are dry and prime them if needed.
- New sealant goes in, with baths filled first so they’re at their heaviest.
- The finished joints are checked and the cure times given.
Getting ready for the visit
- Where the joints are inside, avoid wetting them before we arrive
- Clear items away from the joints we are working on
- Mention any parking rules near the property
Get a quote
If you are in East Dulwich and need new build mastic, ring 0345 464 0079 or send us an email. A short description of the job and where it is helps us quote, and we will agree the price before any work begins.
Advice
New build mastic in East Dulwich: local notes
London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Many of London’s new homes are flats in bigger developments, where snagging may go through the developer or managing agent.
As a London address, East Dulwich can be tricky for parking: let us know about parking bays, permits or a driveway.
East Dulwich is about 3 miles south of London, in Greater London. Homes, rented property, offices and hotels in East Dulwich is covered for new build mastic. The work is guaranteed for a year. Our Greater London coverage runs to 764 places, and East Dulwich is one of them.
Jobs for new build mastic in SE5, SE22 and SE15 is quoted and booked the same way as anywhere else. If you need new build mastic at a property on Rye Lane, Wren Road and Adys Road or a nearby road, our applicators can take on the job. With the A2214 and A2215 close by, East Dulwich is easy for our applicators to reach for new build mastic. Nearby, we also carry out new build mastic in Denmark Hill (1 mile north-west), Herne Hill (1 mile south-west), Dulwich Village (1 mile south), Camberwell (1 mile north) and Peckham (1 mile north-east). Within a short drive, we also cover London (3 miles north), City of Westminster (5 miles north-west), Marylebone (5 miles north-west), Kensington (6 miles north-west), St Pancras (5 miles north) and Shoreditch (4 miles north).
Around East Dulwich
Locally, jobs take us to homes and businesses close to The Fox on the Hill pub, The Charter School East Dulwich and The Charter School and the streets around them. There’s a railway station in East Dulwich itself: East Dulwich station. Other landmarks nearby include House of Dreams Museum (within half a mile south-east) and Surrey Quays Shopping Centre (2.8 miles north-east). Not far away are Knight's Hill and Centre for Wildlife Gardening.
For landlords and businesses
We regularly work with letting and managing agents. Tell us the address, the job and how access works and we will quote.
Landlords and letting agents in East Dulwich can book us as well as householders. Resealing between tenancies is a simple way to keep a property in good order.
Nearby places to East Dulwich
Also in East Dulwich
What sealant work cannot fix
We’d rather tell you now than do work that will not last, so these are the limits:
- Leaks from pipes, valves or wastes, which need a plumber
- A tray or bath that is not properly supported, until it’s fixed
- Deciding who is responsible under a builder’s warranty
If in doubt, phone 0345 464 0079 or drop us an email and we will say what we think.
Where we work in East Dulwich
- Skirting & floors
- Plot handovers
- Kitchens
- Bathrooms & en suites
- Show homes
- Windows & doors
When to call us in East Dulwich
The first winter with the heating on dries a new home quickly. Gaps open along skirting, frames and worktops and cracks appear in the sealant.
Most people get in touch when they notice something like this:
- New-build shower sealant that has already split
- Untidy sealant flagged on a snagging list
- Skirting joints opening in the first winter
- Kitchen sealant that has pulled off the wall
For new homes near East Dulwich station, it’s worth checking the sealant early, while snags are still fresh.
What to look for in a quote
- How long to leave it before use
- How much experience the applicator has
- How the colour is chosen
- Which sealant they’ll use, and why
Questions from East Dulwich
Is parking a problem for a job in East Dulwich?
Parking in East Dulwich, as in most of London, takes a little planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
Do you work for landlords with property near East Dulwich station?
Yes. We work for landlords and letting agents as well as homeowners. You can ring 0345 464 0079 or email us with the details for a clear quote.
What colour sealant will you use?
It depends on the joint: white or clear for most sanitary joints, colours for worktops, floors and frames. We’ll agree it with you first.
Does someone need to be in?
For indoor joints, yes, someone needs to let us in. Once we’ve agreed the job, you don’t need to watch us work.
Which products do you use?
We choose the sealant for the joint, not the other way round. Where it moves, gets wet or faces the weather makes a difference, and we will tell you what we’re using.
Will there be a smell?
Sometimes, a little. Any smell clears as the sealant cures.
Can you work from my snagging list?
Yes. Send us the sealant items on the list, with photos if you can. We’ll flag anything that needs another trade.
Do you take on second-fix sealing for builders?
Yes. We carry out plot mastic and second-fix sealing for builders and developers. Send us the plot schedule and we’ll quote.
What the job involves on each surface
Kitchens
As a new house dries, worktops and walls shift a little, opening gaps behind the upstand. We reseal them with a flexible sealant.
Bathrooms and en suites
Baths, showers, basins and trays in new bathrooms are the most common new-build reseal. The old sealant comes out and anti-fungal sanitary silicone goes in after cleaning and priming.
Why act early in East Dulwich
If you are still in the builder’s snagging or warranty period, ask them to put it right first. If it keeps failing or is not dealt with, we can reseal it properly. 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 for homes in East Dulwich.
What it costs depends on the size of the job, how hard the old material is to remove and how easy the joints are to reach. You’ll have a clear quote before any work starts.
Why choose Mr Mastic in East Dulwich
- 20+ years of sealant experience
- ARBOMaster approved applicator
- A 12-month guarantee on all work
- Fully insured