Greater London · England
Becontree External Mastic
Specialist external mastic for Becontree: careful preparation, the right product and tidy work. Ask us for a quick quote.
- Leaking joints around cladding and façade panels
- Old sealant gone brittle and cracked
- Rigid filler in a joint that should flex
Aftercare tips
So the new joints stay in good condition:
- Tell anyone working on the walls about the movement joints
- Keep water from gutters off the wall
- Walk round the building once a year and look at the joints
- Have failed joints looked at early
Make sure anyone working on the wall later knows where the movement joints are. They should be kept open and resealed, not filled.
Leave a failed movement joint and water keeps getting into the wall. That can lead to damp patches, staining and frost damage which cost more to put right than the joint.
External mastic for homes and businesses in Becontree
Short cuts in external joints show up within a season or two. New sealant over old, joints packed with mortar and beads with no backing all tend to fail early. We take the old material out and do it properly. Typical jobs include failed sealant between panels on a façade and movement joints filled with mortar instead of sealant, across joints between brick and frames, render & cladding joints and façade panels.
Modern London flats rely on sealed movement joints and cladding joints. Older terraces have their own weak points: gutter joints, roofline trims and the joint where an extension meets the original wall.
Whatever the size of the job, it’s backed by our one-year guarantee in Becontree and across Greater London.
- Location
- Becontree (RM9, RM10, RM8)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Quote
- A clear quote up front
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Can I do it myself?
The biggest DIY mistake is sealing over old sealant. Silicone doesn’t stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
If you’re set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
Becontree: your questions answered
Can you help a landlord with a rental near Chadwell Heath station?
Yes, landlords and agents are among the people we work for, and several properties can go on one quote. You can call 0345 464 0079 or email us with the details for a clear quote.
Can parking be tricky for a visit in Becontree?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
Do you have insurance?
Yes. We’re fully insured, and we can confirm the details when we quote.
Will you leave a mess?
No. We protect the surfaces around the joints, and we clear up the old sealant and our materials before we leave.
Can you seal joints between render and window frames?
Yes. Joints between dissimilar materials are a big part of external work. We use a flexible sealant suited to both surfaces, primed where needed.
Is the work guaranteed?
Yes, always. There’s a 12-month guarantee on every job, wherever you are.
Where are you based?
Our base is Crawley. We work across South East England, London and Scotland.
Can you match the colour of my brickwork?
We aim for a joint that suits the wall rather than one that jumps out. Colour is agreed with you before we begin.
When to call us in Becontree
Poor preparation causes many early failures: joint faces that were dusty or damp, unprimed where they needed it, or still carrying old sealant. The sealant never bonds properly.
Look out for these signs:
- Rigid filler in a joint that should flex
- Gaps where render, brick and frames meet
- Failed sealant between panels on a façade
- Damp patches traced to an open external joint
Becontree is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book.
Comparing quotes
- Who turns up on the day
- When the joint can take water or movement
- What happens if the job turns out different
- How the colour is chosen
Places near Becontree
What else we do in Becontree
What the job involves on each surface
Render joints
Rendered walls have joints at beads, openings and changes of material. They’re resealed in a sealant that suits the render.
Concrete and blockwork
Wide joints in concrete need the depth controlling carefully. Backing rod sized to the joint sets it.
Why deal with it now?
Pointing a movement joint with mortar might seem a neat fix, but it stops the joint moving. The movement then cracks the brickwork or render nearby. The correct repair is a flexible sealant with the right backing. Converted houses in London often have a bathroom above someone else’s living room, and a slow leak from a failed seal can end up in the flat below. Putting it right early is much less trouble.
Some things make a job bigger or smaller: how much old sealant there is and how stubborn it is, any mould to treat, and whether we need extra access for height. We take all of that into account in your quote.
What you get with us
- A choice of colours where the product allows
- 4.9 on Google from 180+ five-star reviews
- Colour picked to suit the job
- Neat joints and a tidy finish
See what affects the cost and our reviews.
What sealant work cannot fix
Honest advice matters more to us than a booking, so here’s what new sealant won’t do:
- Render that is blown, hollow or coming away
- Cutting new joints into brickwork, which is building work rather than sealant work
- Subsidence or other structural problems
If in doubt, call 0345 464 0079 or drop us an email and we will say what we think.
Surfaces we seal
- Copings & trims
- Render & cladding joints
- Concrete & block
- Façade panels
- Joints between brick and frames
- Brickwork movement joints
What external mastic looks like in Becontree
London terraces and converted houses often share gutters, downpipes and walls, so check who is responsible for the outside before booking. Rainfall in the South East is lower than in much of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
If you look after a building such as St Joseph's Catholic Primary School, movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. Rented homes near Chadwell Heath station change hands often, and failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Becontree is about 2 miles north-east of Barking, in Greater London. Homes, rented property, offices and hotels in Becontree is covered for external mastic, old or new, large or small. Every job comes with our one-year guarantee. Across Greater London, we cover 764 places, Becontree among them. We also work in London, about 11 miles from Becontree.
We work across RM9, RM10 and RM8 for external mastic and the streets around it. If you need external mastic at a property on Wood Lane, Eliot Road and Maxey Road or a nearby road, our applicators can take on the job. Becontree is on the A1240, so it’s easy for us to get to with everything needed for external mastic. Other places close to Becontree include Dagenham (1 mile south-east), Becontree Heath (1 mile north), Castle Green (1 mile south-west), Dagenham Green (1 mile south) and Goodmayes (2 miles north-west). We also work in nearby towns such as London (11 miles west), City of Westminster (13 miles west), Marylebone (13 miles west), Kensington (15 miles west), St Pancras (11 miles west) and Shoreditch (10 miles west).
Local landmarks in Becontree
Around Becontree, our work takes us to homes and buildings near Eastbrook pub, Robert Clack School and Parsloes Park, among other places. For rail, the closest station is Chadwell Heath station, roughly 1.5 miles north-west. Other landmarks nearby include Redbridge Museum (3 miles west) and The Brewery (2.4 miles north-east). The countryside around Becontree includes Dagenham Village Churchyard.
The process
Our applicators work methodically: protect, prepare, seal, tidy. For most jobs that takes a few hours to a few days, depending on the length of joint and the access, and the area is left clean. In Becontree, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- The faces are brushed clean and primed where the product requires it.
- We fit closed-cell backing rod to control the depth.
- We apply the sealant, tool it and check the whole run.
Before we arrive
- Tell us about access, such as stairs, a lift or high-level joints
- Keep pets and children clear of the area while we work
- Let us know about parking restrictions
How to get a quote
We do not publish a price list, as no two jobs are quite the same. Instead, we send you a clear quote for your job. To arrange one, phone 0345 464 0079 or drop us an email.