Greater London · England
New-build mastic & snagging in Friern Barnet, Greater London
New build mastic across Friern Barnet and nearby, with old sealant always removed completely and a one-year guarantee.
- Gaps between new skirting and floors
- Sealant applied over dusty or wet surfaces
- New-build shower sealant that has already split
New build mastic in Friern Barnet
A new build should have a neat, sound bead at every joint. When the finish is smeared, patchy or already cracking, it’s worth putting right early, before water gets into the floor or walls. We work on windows & doors, kitchens and bathrooms & en suites, and common reasons people get in touch are cracks appearing as a new home settles and frame joints opening as the plaster dries.
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.
The work is covered for a year after we finish. If anything isn’t right with it, phone 0345 464 0079 or drop us an email.
- Place
- Friern Barnet (N11, N12, N10, N20)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Quote
- A clear price before we start
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Questions from Friern Barnet
Do you work for landlords with property near New Southgate station?
Yes, rental work is part of what we do. You can phone 0345 464 0079 or drop us an email with the address and a few details, and we’ll give you a fixed price before any work starts.
Is Friern Barnet in your area for new build mastic?
Yes, Friern Barnet is within the area we cover. Our work covers London and the South East. Just phone 0345 464 0079 or email us with a few details of the job, and we will give you a clear quote.
Will the old sealant be removed?
Always. Sealing over old sealant is the main reason resealing fails early, so we never do it.
Can I add another job to the visit?
Yes. More than one area can go on one quote.
What sealant do you use?
Quality sealants from brands including Arbo and Everbuild, picked for each joint. We’ll tell you what we are using and why.
Will you just run a new bead over the existing one?
No. New silicone won’t bond to old silicone, so sealing over the top fails quickly. We cut the old bead out completely.
Do I have to be there?
Access is agreed with you when the job is booked. Indoors, that generally means someone at home.
My new home is still under warranty. Should I contact you?
Start with your builder while their snagging or warranty period runs. After that, or if their repair keeps failing, we can do it with our one-year guarantee.
What we do, step by step
There’s no need to move everything out, only the area right around the joints. Everything nearby is protected, and the work takes a few hours in a single home in most cases. For a job in Friern Barnet, parking and access are the things to plan: let us know about parking, the floor we’ll be working on and any lift or shared entrance.
- We start by going through the snagging items or plot schedule with you.
- Every bit of the old builder’s sealant is cut out, with no layer left behind.
- Joints are vacuumed and cleaned of building dust.
- Primer goes on where the surface and product need it, then the new sealant.
- We tool every joint neatly and tell you when each area can be used.
Getting ready for the visit
- Let us know about parking restrictions
- Let us know if you’ve seen damp or leaks
- Let us know about stairs, lifts or work at height
Get a quote
We do not publish a price list, as no two jobs are quite the same. Instead, we give you a clear quote for your job. To get started, phone 0345 464 0079 or send us an email.
Related advice
Different surfaces, different methods
Plot handovers
We work through plots to your schedule, sealing each room ready for handover. Each joint is cleaned and primed where needed so the sealant lasts.
Bathrooms and en suites
Shower trays in new homes often move slightly in the first year. The joint is stripped back before the new bead goes in and baths are filled before sealing.
For landlords and businesses
For anyone letting property in or around Friern Barnet, jobs at different addresses can be quoted together. Just tell us the addresses and what each one needs.
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.
Keeping the joints in good condition
Simple care keeps the joints in good condition. Our advice:
- Act quickly if a seal starts to leak
- Avoid running a DIY bead over the old one
- Ventilate bathrooms well, especially in the first year
- Clean sealant with mild detergent, not abrasives
Clean the sealant with a mild detergent and a soft cloth. Keep scourers and harsh chemicals off it, which can damage the surface.
Early snagging is easier snagging. Left alone, a small crack can become a leak.
Nearby places to Friern Barnet
Other services in Friern Barnet
Can I do it myself?
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions.
Overfilling a joint is a classic DIY mistake. A heavy bead looks messy and copes badly with movement, and getting the depth right matters as much as the look.
Joints and finishes in Friern Barnet homes
Many of London’s new homes are flats in bigger developments, where snagging may go through the developer or managing agent. Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
As a London address, Friern Barnet can be tricky for parking: let us know about parking bays, permits or a driveway. If you’ve bought a new home near New Southgate station, the sealant around baths, showers and frames is worth checking in the first year or two.
Friern Barnet is about 2 miles north-east of Finchley, in Greater London. Whether you are in the middle of Friern Barnet or further out, we cover new build mastic for every kind of property, from flats and houses to offices and hotels. Our Greater London coverage runs to 764 places, Friern Barnet among them. There’s also a page for London, roughly 8 miles from Friern Barnet.
Our applicators cover all of the N11, N12, N10 and N20 postcode area for new build mastic. That includes homes and businesses on Martock Gardens, Shapwick Close and Radstock Close. Friern Barnet sits on or near the A406 and B550, so getting to you is simple. Neighbouring places we cover for new build mastic include New Southgate (1 mile east), Brunswick Park (1 mile north), North Finchley (1 mile west), Arnos Grove (1 mile east) and Whetstone (1 mile north-west). Larger places within reach include London (8 miles south), City of Westminster (7 miles south), Marylebone (7 miles south), Kensington (8 miles south), St Pancras (6 miles south) and Shoreditch (7 miles south-east).
Landmarks near Friern Barnet
In Friern Barnet, that means homes and buildings near Francis Skaryna Belarusian Library and Museum, Friary Park and Friern Barnet School. There’s a railway station in Friern Barnet itself: New Southgate station. Nearby you’ll also find Francis Skaryna Belarusian Library and Museum (1.4 miles west) and Grand Arcade (1 mile west). The countryside around Friern Barnet includes Highgate Hill and Darland's Lake.
When something else is needed
Honest advice matters more to us than a booking, so here’s what new sealant will not do:
- Movement caused by a poorly fitted tray or bath
- Plumbing faults behind the sealant
- Your warranty claim itself, which is between you and the builder
If you’re not sure, just ring 0345 464 0079 or email us and we will give you a straight answer before you book.
Joints and surfaces we work on
- Skirting & floors
- Show homes
- Windows & doors
- Plot handovers
- Kitchens
- Bathrooms & en suites
What happens if it’s left?
A tube of sealant from the DIY shop will not fix the cause: grit, unprimed surfaces and old layers underneath. Proper removal and preparation are what make it last. Converted houses in London often have a bathroom above someone else’s living room, so a small leak from tired sealant can mean a neighbour’s ceiling and a lot of disruption. Putting it right early is much less trouble for homes in Friern Barnet.
The cost depends on the size of the job, how hard the old material is to remove and access to the work. You’ll have a clear quote before any work starts, so you know where you stand.
Why book with us
- Old sealant always removed completely
- White, clear, grey or coloured to suit, where the product allows
- You choose the colour before work begins
- Tidy, careful work
Read what affects the cost or our reviews.