Greater London · England
New Build Mastic in Hampstead
New build mastic across Hampstead and nearby, with every bit of old sealant taken out first and a one-year guarantee.
- Smeared, uneven beads picked up at snagging
- New-build shower sealant that has already split
- Gaps behind new kitchen upstands
Hampstead: your questions answered
Is parking an issue for new build mastic in Hampstead?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
Is Hampstead in your area for new build mastic?
Yes, Hampstead is within the area we cover. We work across London and the South East. Just ring 0345 464 0079 or email us with a few details of the job, and we will send you a clear quote.
Is there any odour?
There can be a smell while the sealant cures, which fades as it sets. Opening a window helps.
Can tenants book the work?
We are happy to deal with the tenant, landlord or agent. Just make sure your landlord agrees.
Do I need to be at home?
If the work is inside, we need someone to let us in. After that, you can carry on with your day.
My new home is still under warranty. Should I contact you?
While the snagging or warranty period runs, the builder should be your first contact. If they’re slow or the fix doesn’t last, we can help.
Can landlords and businesses book you?
Yes, we do. We work in homes, commercial premises and hotels.
Where are you based?
We are a Crawley-based firm. Our area covers South East England, London and Scotland.
New build mastic in Hampstead, done properly
Some owners wait for the first year’s movement before having joints redone. That makes sense for small gaps that are just cosmetic, but a failed shower or bath seal shouldn’t wait. If you’re dealing with cracks appearing as a new home settles and messy sealant that spoils new finishes, we can help, whatever the surface.
Across London, commercial floors have movement joints that break down under heavy foot traffic, and new homes need their plot mastic finished properly before handover.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we will put it right.
- Where
- Hampstead (NW3, NW6, NW11, N2)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Quote
- A clear price before we start
- Call
- 0345 464 0079
- Updated
- 26 October 2026
DIY versus a professional finish
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, then guaranteed for a year.
If you are 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 doesn’t work out, we can still put it right.
How the job changes by surface
Skirting and floors
As timber and screed dry, skirting and floors shift. We use a flexible product rather than caulk.
Windows and doors
External mastic around new windows and doors is sometimes rushed or missed. We reseal it with a weatherproof, flexible sealant.
Also near Hampstead
What else we do in Hampstead
For landlords and businesses
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements and we’ll quote.
From a single let to a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a one-year guarantee.
When something else is needed
We will always be straight with you, so here’s what new sealant won’t do:
- Leaking fittings rather than failed sealant
- Your warranty claim itself, which is between you and the builder
- Broken tiles or a split tray
If in doubt, call 0345 464 0079 or send us an email and we’ll say what we think before booking.
Surfaces we seal
- Bathrooms & en suites
- Windows & doors
- Kitchens
- Skirting & floors
- Plot handovers
- Show homes
Why act early in Hampstead
If you’re still in the builder’s snagging or warranty period, ask them to put it right first. If it’s slow, or the same joint keeps failing, a proper reseal from a specialist is the next step. In a flat in Hampstead, 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.
The cost depends on how much there is to do, how hard the old material is to remove and access to the work. We give a clear quote before work begins.
Why choose Mr Mastic in Hampstead
- Anti-fungal silicone where joints get wet
- Quality sealants from Arbo and Everbuild
- White, clear, grey or coloured to suit, where the product allows
- Colour agreed with you before we start
Take a look at our cost guide and what customers say.
Aftercare tips
No joint lasts for ever, but care makes a real difference. A few tips:
- Do not wait for the house to settle if water is getting through
- Use the extractor fan every time you shower
- Keep pictures and emails about snagging items
- Resist patching a failed seal with a tube from the DIY shop
Ventilation matters in a new home, which is still drying out. Run the fan or open a window after bathing to help keep mould away.
Report failed sealant to the builder while you’re in the snagging period. After that, putting it right may fall to you so report it promptly.
New homes and floors in Hampstead
The South East is one of 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 snags may need reporting through the developer or the managing agent.
For new homes near Finchley Road & Frognal station, it’s worth checking the sealant early, while snags are still fresh. Hampstead is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Hampstead is about 3 miles north-west of City of Westminster, in Greater London. For new build mastic in and around Hampstead, it’s easy to get a quote: please call 0345 464 0079 or drop us an email. We cover Greater London from our Crawley base. We cover 764 towns and villages across Greater London, from the larger towns to small villages.
Work in NW3, NW6, NW11 and N2 works the same way as everywhere else we cover. Whether your property is on Hampstead High Street, New End Square and The Mount Square or anywhere close by, our applicators can take on the job. Main roads around Hampstead include the A1 and A502, which makes travel easy. We also cover Greenhill (1 mile north-east), West Hampstead (1 mile west), Fortune Green (1 mile west), Vale of Health (1 mile north) and South Hampstead (1 mile south). Within a short drive, we also cover London (5 miles south-east), City of Westminster (3 miles south-east), Marylebone (3 miles south-east), Kensington (4 miles south), St Pancras (3 miles south-east) and Shoreditch (5 miles south-east). Hampstead is among the bigger towns we cover in Greater London.
Around Hampstead
We work in homes and buildings around South Hampstead High School, Kilburn Grange Park and St Anthony's Preparatory School. Nearby too are King William IV Public House (less than half a mile north-east) and Cecil Sharp House (1.7 miles south-east). Hampstead has its own railway station: Finchley Road & Frognal station. Well-known places in the area include Isokon Gallery (0.8 miles east) and New End Hospital (less than half a mile north). Green spaces nearby include Belsize Wood and The Long Water.
What happens on the day
A visit follows a simple pattern: we look at the joints together, mask and protect the surrounding surfaces, carry out the job and clear up. It generally takes a few hours for most snagging lists, longer for a run of plots. In a London area like Hampstead, 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.
- Each joint is checked for movement before any work starts.
- We remove the failed sealant and clean the joints.
- We make sure the joints are dry and prime them if needed.
- Baths are filled with water, then the new sealant is applied.
- The finished joints are checked and the cure times given.
How to prepare
- Mention any tricky access
- Let us know about parking restrictions
- Keep pets and children clear of the area while we work
Getting a quote
There’s no standard price list, as no two jobs are quite the same. Instead, we give you a clear price for your job. To arrange one, ring 0345 464 0079 or send us an email.