Greater London · England
New-build mastic & snagging in Dulwich Village, Greater London
Plot mastic for developers and snagging failed sealant in new homes in Dulwich Village, with a 12-month guarantee on every job. Ask us for a quote.
- Sealant that never bonded to the surface
- Joints pulling apart as timber shrinks
- Sealant work across a run of new homes
New build mastic in Dulwich Village, done properly
We carry out plot mastic and second-fix sealing for builders, and snagging reseals for new-home owners. Both get the same care over preparation, because that is what rushed new-build sealant usually lacks. We work on windows & doors, skirting & floors and kitchens, and common reasons people get in touch are shower seals failing in the first year or two and gaps between new skirting and floors.
London homes range from new-build flats to period conversions with new floors laid over old boards. Every joint between floor, skirting and threshold has to cope with some movement.
Whatever the size of the job, it’s backed by our 12-month guarantee in Dulwich Village and across Greater London.
- Where
- Dulwich Village (SE22, SE21, SE24)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Keeping the joints in good condition
Looking after new joints is easy:
- Report sealant problems to your builder during the snagging period
- Avoid running a DIY bead over the old one
- Wait for the cure time before using a resealed shower
- Get a leaking seal dealt with right away
Ventilation matters in a new home, which is still drying out. Run the fan or open a window after bathing.
Don’t let the snagging period run out with sealant problems unreported. Once it ends, the repair may be down to you, so raise it early.
Common questions in Dulwich Village
Do you work for landlords with property near North Dulwich station?
Yes, we work for letting agents and landlords. Just ring 0345 464 0079 or drop us an email and tell us about the property, and we will give you a clear quote.
Do you cover Dulwich Village for new build mastic?
Yes. Our work covers London and the South East, and Dulwich Village is part of that. You can phone 0345 464 0079 or send us an email and tell us what needs doing, and we’ll send you a clear quote.
Do you have insurance?
Yes. Mr Mastic is fully insured, and we have been doing sealant work for more than 20 years.
When is the sealant fully cured?
That depends on the sealant used, so please follow the time we give you when we finish.
Does someone need to be in?
We need access to the joints, so we will agree that with you when we book. Indoors, that usually means someone at home.
How long does the job take?
Most jobs take a few hours in a single home, including preparation and clearing up. We will confirm how long when we quote.
Which products do you use?
Products from Arbo and Everbuild, among others, picked for each joint. We will tell you what we’re using and why.
Can you reseal over the builder’s sealant?
No. The old sealant is cut out fully, the joint cleaned and primed where needed, and a new bead applied.
Landlords, agents and businesses in Dulwich Village
Letting agents often deal with us directly. Tell us the address, the job and how access works and we will quote.
Hotels need rooms back in use, so we plan the work room by room. Hotel work is part of what we do, alongside homes and businesses.
What new build mastic looks like in Dulwich Village
The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. Many of London’s new homes are flats in bigger developments, where snagging may go through the developer or managing agent.
Dulwich Village is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Dulwich Village is about 1 mile south-east of Herne Hill, in Greater London. Dulwich Village gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a 12-month guarantee. Dulwich Village is one of 764 places in Greater London where we work.
Every address in SE22, SE21 and SE24 is covered for new build mastic, from the main roads to the quietest streets. New build mastic is available to properties on Court Lane, Druce Road and Turney Road. Dulwich Village is on the A2216, so it’s easy for us to get to. Neighbouring places we cover for new build mastic include Dulwich (1 mile south-east), Herne Hill (1 mile north-west), East Dulwich (1 mile north), West Dulwich (1 mile south) and Denmark Hill (1 mile north). Further out, 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 (5 miles north).
Landmarks near Dulwich Village
We work in homes and buildings around Alleyn's School, The Crown and Greyhound pub and The Charter School and the streets around them. There’s a railway station in Dulwich Village itself: North Dulwich station. A little further out are Lewisham Shopping Centre (3.2 miles east) and Greenwich Castle (4 miles north-east). Open spaces near Dulwich Village include Knight's Hill and Centre for Wildlife Gardening.
What we do, step by step
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 normally takes anything from a few hours to several days, depending on the number of plots. 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 go through the snagging list or plot schedule and agree the joints to do.
- The old bead comes out in full, with no layer left behind.
- We clean off dust from the build and prime the surfaces where the product needs it.
- We apply a sealant that suits each joint and tool it to a neat finish.
- Finally, each room is checked and you’re given the cure time.
Getting ready for the visit
- Clear items away from the joints we are working on
- Let us know about stairs, lifts or work at height
- Keep children and pets away from the work area
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 will take it from there.
Advice
Nearby places to Dulwich Village
What else we do in Dulwich Village
DIY versus a professional finish
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
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.
What affects the cost of new build mastic
Your quote is based on your job. We take into account:
- Whether the work is at height
- The type of sealant required
- Mould in or behind the old joints
- The size of the job
Leaving a failed joint generally makes the job bigger, not smaller, as water and mould keep getting in. If you’re not sure whether it needs doing, ring 0345 464 0079 or drop us an email for an honest opinion and a quote.
What to tell us for a quote
When you call or email, it’s useful to know:
- Access, such as stairs, a lift or height
- If someone has resealed it before
- Where the job is, and your postcode
- What’s wrong with the joints now
Need a quote? 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 work begins.
What happens if it’s left?
DIY kits don’t solve the main problems with new-build sealant: dust, no primer and old sealant left in the joint. Cutting out, cleaning and priming are what make the difference. 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 generally makes better use of the time than several visits, so it’s worth mentioning everything you’d like done. We’ll give you a clear quote for the lot.
What you get with us
- A choice of colours where the product allows
- Rated 4.9 stars on Google
- Old sealant always removed completely
- We leave the area clean and tidy
See what affects the cost and customer reviews.
Do you need new build mastic in Dulwich Village?
When the heating goes on in the first winter, the house dries fast. Skirting, frames and worktops pull away slightly.
If you can see any of these, it’s time to have the joints looked at:
- Plot mastic for developers ahead of handover
- Frame joints opening as the plaster dries
- Kitchen sealant that has pulled off the wall
- Sealant applied over dusty or wet surfaces
If you’ve bought a new home near North Dulwich station, the sealant around baths, showers and frames is worth checking in the first year or two.
What to look for in a quote
- Whether the sealant suits the joint
- How much experience the applicator has
- What the quote includes, VAT included or not
- Which colour the sealant will be