Greater London · England
New-build mastic & snagging in North End, Greater London
New build mastic for North End and the surrounding area: the right sealant, proper preparation and a neat finish. Ask us for a quick quote.
- Worktop and upstand sealant coming away
- Cracked caulk along new skirting
- Cracks appearing as a new home settles
New build mastic in North End, done properly
Dust is the enemy of new-build sealant. We clean every joint thoroughly and prime where the surface and product need it, so the sealant actually sticks rather than sitting on a layer of grit. If you’re dealing with untidy sealant flagged on a snagging list and gaps between new skirting and floors, we can put it right.
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 North End as anywhere.
Each job carries a 12-month guarantee.
- Where
- North End (DA8, DA1, DA7)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Quote
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Should I try it myself first?
If you’ve already had a go yourself, that’s fine. We cut it out and start again, so tell us about it when you ask for a quote.
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
The process
Before we leave, we go over the finished joints with you and explain the cure time. The work normally takes anything from a few hours to several days, depending on the number of plots, depending on the size of the job. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- We go through the snagging list or plot schedule and agree the joints to do.
- We cut out every bit of the failed or messy sealant.
- We clean off dust from the build and prime the surfaces where the product needs it.
- A sealant chosen for each area goes in and is tooled smooth.
- We check every joint and tell you how long each needs to cure.
Before we arrive
- Move anything stored near the joints
- For business premises, tell us about site rules or sign-in
- Let us know about earlier repairs to the joints
Ask for a quote
Asking for a quote is easy: let us know the job and the location, and roughly how big it is. A few pictures by email make the job easier to understand, and we will take it from there.
Read more
Common problems we fix in North End
The first winter with the heating on dries a new home quickly. Skirting, frames and worktops pull away slightly and cracks appear in the sealant.
The most common problems we see are:
- Second-fix sealing on new plots
- Joints pulling apart as timber shrinks
- Cracked caulk along new skirting
- Shower seals failing in the first year or two
As a London address, North End can be tricky for parking: let us know about parking bays, permits or a driveway.
What your quote should include
- Which colour the sealant will be
- What the cure time is
- What product goes in the joint
- Is the old sealant removed completely?
Work for landlords, hotels and businesses
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements and we will give you a quote.
We also work for businesses, from offices to washrooms and kitchens. On commercial sites, working times can be discussed when we quote.
Questions from North End
Can parking be tricky for a visit in North End?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. The visit is then planned around what’s available.
I let a flat near Slade Green station. Can you help?
Yes, we work for landlords and letting agents. You can ring 0345 464 0079 or send us an email with the address and a few details, and we’ll give you a fixed price before any work starts.
Can you quote for more than one area?
Of course. Doing several areas at once is normally more efficient, so mention them when you ask for a quote.
Are you an approved applicator?
Yes. We are ARBOMaster approved, the scheme for applicators of Arbo sealants.
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 agree the colour before any work starts.
Do I need to be at home?
It depends on the job. For work indoors, someone needs to let us in, while outside work can sometimes be arranged differently.
Do you have insurance?
Yes. Mr Mastic is fully insured, with over 20 years’ experience in sealant work.
Is it normal for sealant to crack in a new home?
A new house dries and settles for a year or two, and sealant is often rushed onto dusty, unprimed surfaces. Both lead to early failure.
New build mastic in North End: local notes
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.
If you’ve bought a new home near Slade Green station, the sealant around baths, showers and frames is worth checking in the first year or two.
North End is about 2 miles north-west of Dartford, in Greater London. Jobs in North End get the same care as everywhere else we work: old sealant removed completely, careful preparation and a one-year guarantee. 764 places in Greater London are on our list. Our London page covers work nearby.
Every address in DA8, DA1 and DA7 is within our area for new build mastic, from the main roads to the quietest streets. Streets in the area include Oak Road, Elm Road and Moat Lane. We also cover Slade Green (1 mile east), Barnes Cray (1 mile south), Bexley Riverside (1 mile west), Barnehurst (1 mile west) and Northumberland Heath (1 mile west). Further out, we also cover London (13 miles west), City of Westminster (15 miles west), Marylebone (15 miles west), St Pancras (14 miles west), Shoreditch (12 miles west) and Walthamstow (13 miles north-west).
Around North End
We work in homes and buildings around Railway Tavern, Braeburn Park and Haberdashers' Aske's Crayford Academy and the streets around them. There’s a railway station in North End itself: Slade Green station. Nearby you will also find Erith Museum (1.2 miles north-west) and Erith and District Hospital (1.4 miles north-west). Green spaces nearby include Wansunt Pit.
Keeping the joints in good condition
So the new joints stay in good condition:
- Wipe joints with warm soapy water
- Do not wait for the house to settle if water is getting through
- Ventilate bathrooms well, especially in the first year
- Raise failed sealant with the developer while you are covered
Wipe the sealant with warm soapy water. Avoid abrasive pads and strong solvents as they wear the bead.
Early snagging is easier snagging. Left alone, a small crack can become a leak in a busy bathroom.
Leave it or put it right?
It often makes sense to do all the sealant items on a snagging list together. You get one visit and one clear quote for the lot. 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. Dealing with it early is far simpler.
We don’t show prices on the website, because the cost depends so much on the job itself. Call for a quick quote.
Why us?
- We agree the colour with you first
- We never seal over old sealant
- Neat joints and a tidy finish
- Every job guaranteed for a year
Read what affects the cost and our reviews.
Also near North End
Also in North End
What we cannot put right
Before you book, it’s worth knowing the limits too:
- Leaks from pipes, valves or wastes, which need a plumber
- A tray or bath that isn’t properly supported, until it’s fixed
- Structural cracks in walls or ceilings
Not sure which it is? You can ring 0345 464 0079 or send us an email and we’ll tell you honestly.
What we seal
- Bathrooms & en suites
- Show homes
- Windows & doors
- Plot handovers
- Kitchens
- Skirting & floors