Greater London · England
External Mastic in West Hendon
Professional external mastic in and around West Hendon, with every bit of old sealant taken out first.
- Plants rooting in failed movement joints
- Gaps where render, brick and frames meet
- Leaking joints around cladding and façade panels
External mastic in West Hendon
External mastic is a job where short cuts show quickly. Overfilled joints, missing backing rod and sealant laid over old sealant rarely last long. We take the old material out and do it properly. We work on copings & trims, brickwork movement joints and façade panels, and the jobs we see most are weeds or debris growing in open joints and panel joints letting water in.
London’s terraces and conversions often share walls, gutters and downpipes with their neighbours, so one failed joint can cause damp for more than one household. For a flat in West Hendon, check the lease for who looks after the outside.
All of our work is guaranteed for twelve months.
- Where
- West Hendon (NW9, NW4)
- Region
- Greater London
- Guarantee
- A year, on every job
- Price
- A clear price before work begins
- Call
- 0345 464 0079
- Updated
- 26 October 2026
What external mastic looks like in West Hendon
With historic houses such as Heath House (about 3.2 miles south-east) nearby, there’s older building stock in the area around West Hendon as well as newer homes. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth. London terraces and converted houses often share gutters, downpipes and walls, so check who is responsible for the outside before booking.
As a London address, West Hendon can be tricky for parking: let us know about parking bays, permits or a driveway. For site and facilities teams at buildings such as The Hyde School, its movement joints, gutters and trims need looking after like any other building’s.
West Hendon is about 2 miles north of Neasden, in Greater London. Jobs in West Hendon get the same care as everywhere else we work: old sealant removed completely, careful preparation and a 12-month guarantee. Our area takes in 764 places across Greater London, large and small. We also work in London, around 9 miles away.
Every address in NW9 and NW4 is within our area for external mastic. External mastic is available to properties on Alpini Road, Catkin Road and Garrick Road. You’ll find West Hendon on the A5, which makes it straightforward to reach with everything needed for external mastic. Neighbouring places we cover for external mastic include The Hyde (1 mile south), Colindale (1 mile north), The Burroughs (1 mile north-east), Hendon (1 mile east) and Staples Corner (1 mile south-east). Within a short drive, we also cover London (9 miles south-east), City of Westminster (6 miles south-east), Marylebone (6 miles south-east), Kensington (6 miles south), St Pancras (7 miles south-east) and Shoreditch (8 miles south-east).
Near you in West Hendon
We work in homes and buildings around Woodfield School, Moon Under Water pub and Brampton College and the streets around them. There’s a railway station in West Hendon itself: Hendon station. Other landmarks nearby include Brent Cross Shopping Centre (1.1 miles east) and Church Farmhouse Museum (1 mile north-east). Not far away are Masons Field and Parliament Hill.
What we cannot put right
We’d rather tell you now than do work that will not last, so here’s what sealant cannot put right:
- Render that’s blown, hollow or coming away
- Cracked brickwork or render that needs a builder or plasterer
- Cutting new joints into brickwork, which is building work rather than sealant work
If in doubt, phone 0345 464 0079 or email us and we will say what we think before booking.
Surfaces we seal
- Concrete & block
- Façade panels
- Brickwork movement joints
- Render & cladding joints
- Copings & trims
- Joints between brick and frames
Quotes for external mastic in West Hendon
Your quote is based on your job. We take into account:
- The number of rooms or windows
- When we can work, for business premises
- The product the joint needs
- How much there is to do
Homes and businesses are quoted the same way: the amount of work, how we reach it and what it needs, along with when we can work on site. Call for a quick quote and we will go through it with you.
What to tell us for a quote
When you call or email, it’s useful to know:
- The rough size of the job
- Photos by email, if that’s easy
- If it’s domestic, commercial or a hotel
- Access, such as stairs, a lift or height
Every job is quoted individually, so the first step is telling us about yours. Just ring 0345 464 0079 or send us an email with the details and send pictures if you have them.
How it works
On the day, there’s very little for you to do. Point us to the joints and we will get on with it. The job generally takes a few hours for a handful of joints, longer for a whole elevation from start to finish. 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.
- First we look over the joints with you, agree which to renew and talk through access.
- Old sealant and any debris are cut and raked out.
- Both sides are cleaned back to sound material and primed if needed.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- We gun in a flexible exterior sealant in a colour that suits the wall and tool it neatly.
How to prepare
- Mention any sign-in or site rules at work premises
- Where the joints are inside, avoid wetting them before we arrive
- Tell us about access, such as stairs, a lift or high-level joints
Getting a quote
For a quick quote, get us on the phone, or email us if that’s easier. Describe what needs sealing and we’ll explain what’s involved.
Related advice
What the job involves on each surface
Joints between dissimilar materials
Where a frame or panel meets masonry, water often finds a way in. The old joint is removed and a sealant that bonds to both sides goes in.
Copings and trims
Coping and trim joints face rain and sun head on. We reseal them with an exterior sealant suited to the material.
Places near West Hendon
Also in West Hendon
Do you need external mastic in West Hendon?
Every building moves. Brickwork grows a little over the years, blockwork and concrete shrink, and all of it moves with heat and moisture. The sealant in the movement joints takes that strain.
The problems people usually mention when they call are:
- Rain getting behind render or cladding at a joint
- Brick movement joints where the sealant has split
- Panel joints letting water in
- Weeds or debris growing in open joints
If you let a flat or house near Hendon station, split movement joints are easy to miss on a rental until damp shows inside.
Before you book anyone
- How long the guarantee is
- How the colour is chosen
- Who turns up on the day
- When the joint can take water or movement
Keeping the joints in good condition
Aftercare is simple, and it makes a real difference:
- Avoid pressure-washing directly into sealant joints
- Have failed joints looked at early
- Clear growth from the base of walls and joints
- Fix overflowing gutters above sealed joints
Do not paint over the new sealant unless we’ve said the product is paintable. Paint can crack on a flexible joint.
If you can see gaps, plants or bare sections in a joint, have it checked. Early work is quicker and leaves a better finish.
Why it’s worth doing now in West Hendon
An open joint keeps letting water into the wall with every downpour. In cold weather, frost can damage wet brick and render near the open joint, so the problem grows beyond the joint itself. Damp from a failed joint spreads quietly in older London brickwork and timber, and by the time it shows on a wall or ceiling in West Hendon, the repair is bigger than the sealant job would have been.
What you pay reflects the work, not a rough estimate. That is why we ask about the job first and agree the price before starting.
Why choose Mr Mastic in West Hendon
- Rated 4.9 stars on Google
- We never seal over old sealant
- Sealant colour chosen to suit
- Quality sealants from Arbo and Everbuild
Read what affects the cost or our reviews.
FAQs for West Hendon
Do you cover West Hendon for external mastic?
Yes, West Hendon is within the area we cover. We work across London and the South East. Just call 0345 464 0079 or send us an email with a few details of the job.
Can parking be tricky for a visit in West Hendon?
Parking in West Hendon, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
How do you reach high-level joints?
That depends on the building and the joints. Where joints can be reached safely, we’ll do them. Give us some details and we’ll confirm the access.
What does external mastic cost?
Every job is different, so each one gets its own quote. For a quick quote, ring 0345 464 0079 or drop us an email with a short description of the job.
Will there be a smell?
That depends on the sealant. Some products have a noticeable smell, others very little, and any smell fades as they cure.
Are you insured?
Yes. We’re fully insured, and we’ve been doing sealant work for more than 20 years.
Is there a guarantee?
Yes, always. There’s a 12-month guarantee on every job, large or small.
Do you work for hotels and businesses?
Yes. We’ve worked for hotels, offices and other businesses.