Greater London · England
Tokyngton External Mastic
Professional external mastic in and around Tokyngton, with old sealant always removed completely and a 12-month guarantee.
- Rain getting behind render or cladding at a joint
- Movement joints filled with mortar instead of sealant
- Failed sealant between panels on a façade
External mastic in Tokyngton
We are ARBOMaster approved applicators, and each external joint gets a sealant suited to it. Porous or awkward surfaces are primed where the sealant needs it and we use one wherever it does. Typical jobs include rain getting behind render or cladding at a joint and cracked joints where brick meets render or frames, on render & cladding joints, copings & trims and brickwork movement joints.
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 Tokyngton, check the lease for who looks after the outside.
A one-year guarantee comes with the work, just as it does everywhere we cover.
- Location
- Tokyngton (HA9, NW10, HA0)
- Wider area
- Greater London
- Cover
- One year on every job
- Price
- Quoted before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
DIY versus a professional finish
A DIY attempt does not rule out a professional job. We cut it out and start again, so just mention it when you contact us.
The difference is mostly in the preparation and the product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions.
Tokyngton questions
Do you cover Tokyngton for external mastic?
Yes, Tokyngton is within the area we cover. We work across London and the South East. Just call 0345 464 0079 or email us with a few details of the job.
Can parking be tricky for a visit in Tokyngton?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly.
How long should I leave it?
It depends on the product. Before we leave, we will tell you the cure time.
Can a movement joint be filled with mortar?
No. A mortar-filled joint can’t move, so the wall cracks somewhere else instead. Use a flexible sealant with backing rod.
How often do external joints need resealing?
That varies with the weather the wall faces, how much it moves and the sealant used. Sealant is a maintenance item, so check the joints once a year.
Are you an approved applicator?
Yes. We’re an ARBOMaster approved applicator, the approved applicator scheme for Arbo sealants.
Is it worth trying it myself?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. Most DIY failures come from sealing over old material, wet joints or too much sealant.
Can new sealant go over the old?
No. New silicone will not bond to old silicone, and it traps any mould or water underneath. We remove it all first.
Why act early in Tokyngton
Water gets in through a failed movement joint and can run behind render or cladding. Resealing early keeps the job to the joint itself, instead of the wall and finishes around it. 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 Tokyngton, the repair is bigger than the sealant job would have been.
Doing several joints on one visit generally makes better use of the time than several visits, so it’s worth mentioning everything you’d like done. We will give you a clear quote for the lot.
Why us?
- Arbo and Everbuild products
- Rated 4.9 stars on Google
- Experience in homes, commercial sites and hotels
- Neat joints and a tidy finish
Take a look at how sealant jobs are priced or customer reviews.
Keeping the joints in good condition
Once the sealant has cured, a few habits help it last:
- Clear growth from the base of walls and joints
- Deal with leaking gutters that soak the joints below
- Leave the joints unpainted unless we have said otherwise
- Make sure movement joints are not pointed over
Only paint over the joint if we have confirmed the sealant can take paint. Many exterior sealants aren’t designed to be painted, and paint can crack as the joint moves.
Water getting behind cladding or render can go unnoticed for a long time. By the time there’s a damp patch, the damage can be well established, so it’s worth resealing at the first signs.
Honest limits
Some problems need a builder, plumber or other trade rather than us:
- Adding movement joints to masonry that has none
- Movement that is more than a sealant joint can take
- Cracking across the wall rather than at a joint
If you are not sure, just call 0345 464 0079 or email us and we will give you a straight answer.
Where we work in Tokyngton
- Render & cladding joints
- Copings & trims
- Brickwork movement joints
- Concrete & block
- Façade panels
- Joints between brick and frames
Also in Tokyngton
External mastic in Tokyngton: local notes
Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. London terraces and converted houses often share gutters, downpipes and walls, so check who is responsible for the outside before booking.
Schools such as Elsley Primary School are buildings too, and larger buildings have long runs of movement joint that eventually need resealing. In the older streets around St Michael the Archangel, older walls, gutters and the joints where extensions meet them need a flexible sealant. Letting a property close to Stonebridge Park station? Then failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Tokyngton is about 1 mile south-east of Wembley, in Greater London. Our applicators cover external mastic for homes and businesses in Tokyngton and nearby. Our Greater London coverage runs to 764 places, Tokyngton among them. London is on our list too, around 9 miles away.
We work across HA9, NW10 and HA0 for external mastic and the streets around it. If you need external mastic at a property on Harrow Road, Wycombe Road and Tring Avenue or anywhere close by, we can help. If you are just outside Tokyngton, we cover Stonebridge Park (1 mile south-east), Mapesbury (1 mile north-west), Stonebridge (1 mile south-east), Brent Park (1 mile north-east) and West Twyford (1 mile south). Larger places within reach include London (9 miles south-east), City of Westminster (6 miles south-east), Marylebone (6 miles east), Kensington (5 miles south-east), St Pancras (7 miles east) and Shoreditch (9 miles east).
Landmarks near Tokyngton
Typical jobs here are in homes near The Swaminarayan School, St. Raphael's Edible Garden and Ark Elvin Academy, among other places. There’s a railway station in Tokyngton itself: Stonebridge Park station. Nearby you will also find Brent Museum and Archives (2.1 miles east) and Neasden Hospital (0.7 miles east). Green spaces nearby include Middle Lake and Hanger Hill Wood.
The process
There isn’t much for you to do on the day. Show us the job and we will take it from there. The work itself takes anything from a few hours to several days, depending on the building from start to finish. In Tokyngton, as in most of London, parking needs a little planning. A visitor permit or a nearby bay makes the visit run more smoothly.
- 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.
- The joint faces are cleaned and primed where the sealant needs it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
How to prepare
- Clear items away from the joints we are working on
- Tell us about any previous sealing or DIY attempts
- Mention any leaks or damp you’ve noticed
How to get a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints.
Related advice
What affects the quote in Tokyngton
For a quick quote, just ask. The main things that affect it are:
- The old material and how stubborn it is
- How easy the joints are to reach
- How many rooms, windows or areas are involved
- Any working-time requirements on site
Instead of a standard rate, we price the job in front of us: how many joints, what’s in them now and how we reach them. You will know the price before we begin.
Helping us quote
When you call or email, it’s useful to know:
- Roughly how big the job is
- What the problem is, such as mould, gaps, leaks or cracking
- Any previous sealing or DIY work
- Pictures of the joints, sent by email
Want a quote for external mastic? Please ring 0345 464 0079 or email us and tell us about the job. We’ll explain what we’d do and send you a clear quote before we start.
Different surfaces, different methods
Render joints
Cracks along render joints let water in behind the coat. A sound joint keeps the render dry behind and helps it last.
Concrete and blockwork
The face of concrete or block is often dusty, so cleaning and priming matter. A primer goes on where the product requires one before the bead.