Greater London · England
New-build mastic & snagging in Kingsbury, Greater London
New build mastic across Kingsbury and nearby, with every bit of old sealant taken out first and a 12-month guarantee.
- Skirting joints opening in the first winter
- Sealant applied over dusty or wet surfaces
- Internal frame sealant that has split
About our new build mastic in Kingsbury
A new house keeps drying out and settling for its first couple of years. Timber shrinks, plaster dries and baths and trays bed down, and sealant applied in a hurry at handover can split. If you are dealing with gaps behind new kitchen upstands and new-build shower sealant that has already split, we can put it right.
New flats are going up across London, many of them in larger developments. In a new development, snags are often reported through the developer or the managing agent, and failed shower seals, open skirting joints and gaps at thresholds are typical.
The work is guaranteed for twelve months. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Location
- Kingsbury (NW9, HA3, HA9)
- Region
- Greater London
- Guarantee
- A year, on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
What we’re called out for in Kingsbury
When the heating goes on in the first winter, the house dries fast. Skirting, frames and worktops pull away slightly.
Any of these means the joints need attention:
- Second-fix sealing on new plots
- Messy sealant that spoils new finishes
- Leaking shower tray seals in a new home
- Gaps between new skirting and floors
For new homes near Hendon station, it’s worth checking the sealant early, while snags are still fresh.
Comparing quotes
- Whether you can choose the colour
- How long the guarantee is
- Which sealant they’ll use, and why
- Is the old sealant removed completely?
For landlords and businesses
For anyone letting property in or around Kingsbury, jobs at different addresses can be quoted together. Send us the addresses and the work at each.
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.
What sealant work cannot fix
It helps to know what we cannot do:
- Leaks from pipes, valves or wastes, which need a plumber
- A tray or bath that is not properly supported, until it’s fixed
- Structural cracks in walls or ceilings
If you’re not sure, just phone 0345 464 0079 or send us an email and we’ll give you a straight answer before you book.
What we seal
- Plot handovers
- Windows & doors
- Skirting & floors
- Bathrooms & en suites
- Show homes
- Kitchens
Common questions in Kingsbury
Is parking a problem for a job in Kingsbury?
In much of London, parking needs planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
Do you cover Kingsbury for new build mastic?
Yes, Kingsbury is within the area we cover. We work across London and the South East. You can ring 0345 464 0079 or drop us an email and let us know what needs doing.
What information do you need?
Tell us what needs doing and where. If we need more, we will ask.
Can you work from my snagging list?
Yes. Send us the sealant items on the list, with photos if you can. We will flag anything that needs another trade.
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.
Is there any odour?
That depends on the sealant. Some products have a noticeable smell, others very little.
How long should I leave it?
Many sealants skin over quickly but take longer to cure fully. We will give you the cure time for the product we used before we leave.
Do you work for hotels and businesses?
Yes. Hotels, offices and other businesses use us.
Towns and villages near Kingsbury
Other services in Kingsbury
The process
Once we’re on site, we compare the joints with what we discussed. If anything is different, we explain it before carrying on. Most jobs then take a few hours in a single home. In Kingsbury, flats, stairs and shared entrances are part of the routine. If the building has a concierge, managing agent or access rules, tell us when you book.
- First we work through your snagging list or plot schedule with you.
- Failed or untidy sealant is cut out completely.
- Surfaces are cleaned of building dust and primed where needed.
- New sealant suited to each joint is applied and tooled neatly.
- We check every joint and tell you how long each needs to cure.
Preparing for the visit
- Tell us about any previous sealing or DIY attempts
- Mention any parking rules near the property
- Tell us about access, such as stairs, a lift or high-level joints
Ask for a quote
Getting a quote is simple: tell us what needs doing and where, and roughly how big it is. Photos by email help us understand the job.
Read more
What affects the quote in Kingsbury
You’ll get a clear quote before work begins. It’s based on:
- The number of rooms or windows
- When we can work, for business premises
- The number and length of the joints
- The product the joint needs
A few things move the cost up or down: how much old sealant there is and how stubborn it is, any mould to treat, and whether the work is at height. We take all of that into account in your quote.
Helping us quote
When you contact us, these details help:
- If someone has resealed it before
- A few photos by email, if you can
- How we’d reach the joints
- What the problem is, such as mould, gaps, leaks or cracking
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is, and we’ll talk you through what we’d do. When it suits you, ring 0345 464 0079 or send us an email.
What happens if it’s left?
DIY kits don’t solve the main problems with new-build sealant: grit, unprimed surfaces and old layers underneath. Proper removal and preparation are what make it last. In a London flat, a failed joint rarely stays your problem alone: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
Leaving a failed joint generally makes the job bigger, not smaller, as water and mould keep getting in. If you’re unsure, ring 0345 464 0079 or send us an email for an honest opinion and a quote.
Why choose Mr Mastic in Kingsbury
- Tidy, careful work
- Sanitary silicone with an anti-fungal additive in wet areas
- Approved under the ARBOMaster scheme
- 20+ years of sealant experience
Take a look at what affects the cost or our reviews.
What the job involves on each surface
Windows and doors
A draught at a new window can be a missed or failed joint. We look at the joints and reseal where needed.
Bathrooms and en suites
En suite seals are easy to miss on a snagging list until they leak. Resealing properly keeps water where it belongs.
New build mastic in Kingsbury: local notes
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. Much of London’s new housing is flats in larger developments, where snagging may go through the developer or managing agent.
As a London address, Kingsbury can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Kingsbury is about 2 miles north-east of Wembley, in Greater London. Every kind of property in Kingsbury can book us for new build mastic, old or new, large or small. The work is guaranteed for a year. Our Greater London coverage runs to 764 places, Kingsbury among them. For nearby work, see our London page, about 10 miles away.
Our applicators cover all of NW9, HA3 and HA9 for new build mastic. Whether your property is on Bacon Lane, Slough Lane and Minterne Road or anywhere close by, we can help. Main roads around Kingsbury include the A4006. We also cover Queensbury (1 mile north-west), West Hendon (1 mile east), The Hyde (1 mile east), Preston (1 mile south-west) and Colindale (1 mile north-east). Larger places within reach include London (10 miles south-east), City of Westminster (7 miles south-east), Marylebone (7 miles south-east), Kensington (6 miles south-east), St Pancras (8 miles south-east) and Shoreditch (9 miles south-east).
Local landmarks in Kingsbury
In Kingsbury, that means homes and buildings near JFS, Woodfield School and J.J. Moon's pub. The closest station to Kingsbury is Hendon station, about 1.5 miles east of the centre. Nearby you will also find Church Farmhouse Museum (2.1 miles east) and London Designer Outlet (1.9 miles south). Open spaces near Kingsbury include Castlebar Hill and Darland's Lake.