Greater London · England
Merton Abbey External Mastic
Movement joints in Merton Abbey need attention? We remove the old material, prepare the joints and seal them properly, with a one-year guarantee.
- Failed seals between different materials
- Plants rooting in failed movement joints
- Hard, crazed mastic that has stopped moving
External mastic in Merton Abbey, done properly
We cut out failed sealant, set the joint depth with closed-cell backing rod and reseal with a low-modulus exterior sealant. We pick a colour that sits well with the wall so the joint does not stand out. We work on concrete & block, façade panels and copings & trims, and people most often call us about cracked joints where brick meets render or frames and failed sealant between panels on a façade.
Working on the outside of a London home means planning access: shared paths, upper floors and parking. For a home in Merton Abbey, tell us how high the joints are and how to reach the back of the building.
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.
- Place
- Merton Abbey (SW19, CR4, SW17)
- Region
- Greater London
- Cover
- One year on every job
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Surface by surface
Joints between dissimilar materials
Wherever two materials meet, they move differently. We seal the joint with a flexible exterior sealant so neither cracks the other.
Render joints
Water behind render can lead to blown patches. A sound joint keeps the render dry behind and protects the render itself.
Nearby places to Merton Abbey
More services for Merton Abbey
What affects the cost of external mastic
There’s no set price list, because no two jobs are the same. The quote depends on:
- The number of rooms or windows
- How much there is to do
- When we can work, for business premises
- Whether the work is at height
No two jobs are quite the same, so we quote each one individually. The number of joints, how easy they are to reach and the sealant needed all make a difference, and we’ll explain the quote if you ask.
What to tell us for a quote
You do not need to know the technical terms. Just tell us:
- The address or postcode of the job
- Access, such as stairs, a lift or height
- Any previous sealing or DIY work
- What the problem is, such as mould, gaps, leaks or cracking
If you’re in Merton Abbey and need external mastic, ring 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and we will agree the price before any work begins.
Common questions in Merton Abbey
Can parking be tricky for a visit in Merton Abbey?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
Can you do external mastic in Merton Abbey?
Yes. Our work covers London and the South East, and Merton Abbey is part of that. You can phone 0345 464 0079 or drop us an email and tell us what needs doing.
When will the joints need doing again?
It varies with how exposed the wall is and how much the joint moves. Signs to watch for are cracking, hardening and gaps at the edges and have them redone then.
Do you work for landlords and businesses?
Yes. As well as householders, we work for landlords, agents, businesses and hotels.
Do you guarantee your work?
Yes. All our work carries a 12-month guarantee.
Will the new joint stand out?
We choose a sealant colour to suit the brick, stone or render. There’s a wide choice of exterior colours.
Do I have to be there?
Access is agreed with you when the job is booked. For inside work, that normally means someone being in.
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.
Looking after it afterwards
To keep the joints looking good and working properly:
- Point out the joints to other trades
- Keep water from gutters off the wall
- Look over the joints every year, ideally after winter
- Avoid pressure-washing directly into sealant joints
If you have more work done on the wall, such as new render, cladding or an opening, show the contractor the movement joints. They must stay as flexible joints, never rendered or pointed over.
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 early resealing is worth it.
For landlords and businesses
Letting agents often deal with us directly. Tell us the address, the job and how access works and we will give you a quote.
In hotels, rooms out of use cost money, so we plan the work room by room. Hotel work is part of what we do, alongside homes and businesses.
Do you need external mastic in Merton Abbey?
The wrong product in a moving joint is a classic cause. A high-modulus or general-purpose sealant can be too rigid for a busy joint, and it tears off the sides.
The most common problems we see are:
- Rigid filler in a joint that should flex
- Brick movement joints where the sealant has split
- Old sealant gone brittle and cracked
- Damp patches traced to an open external joint
Schools such as Haslemere Primary School are buildings too, and larger buildings have long runs of movement joint that eventually need resealing.
What your quote should include
- What the cure time is
- What happens if they find a problem under the old sealant
- Which colour the sealant will be
- Is VAT in the price?
DIY sealant or a professional job?
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it lifts and traps water and mould underneath. All the old material has to come out first.
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs call for the right materials, safe access and experience.
External mastic in Merton Abbey: local notes
In terraces and conversions, gutters and walls are often shared with the neighbours, so it’s worth agreeing who is responsible before work starts. London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
If you live in an older home near Christ Church Colliers Wood, an extension built onto an older house moves differently, and the joint between them takes the strain. Merton Abbey is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book.
Merton Abbey is about 2 miles south-east of Wimbledon, in Greater London. If you need external mastic in Merton Abbey, it’s easy to get a quote: please call 0345 464 0079 or send us an email. We cover Greater London from our Crawley base, Merton Abbey included. Across Greater London, we cover 764 places, Merton Abbey among them. There’s also a page for London, about 7 miles away.
Every address in SW19, CR4 and SW17 is within our area for external mastic. Streets in the area include East Road, Hardy Road and Mount Road. You’ll find Merton Abbey on the A24, so it’s easy for us to get to with everything needed for external mastic. Close by, we work in Merton (1 mile west), Colliers Wood (1 mile north-east), South Wimbledon (1 mile north-west), Eastfields (1 mile east) and Tooting Bec (1 mile north-east). Further out, we also cover London (7 miles north-east), City of Westminster (7 miles north), Marylebone (7 miles north), Kensington (6 miles north), St Pancras (8 miles north) and Shoreditch (9 miles north-east).
Near you in Merton Abbey
Around Merton Abbey, our work takes us to homes and buildings near Wandle Park, Ensham School and Rutlish School. For rail, the closest station is Haydons Road station, about 0.9 miles north. Well-known places in the area include St George's Hospital (1 mile north) and Wandle Industrial Museum (0.9 miles south-east). Open spaces near Merton Abbey include Henman Hill and Battersea Park Lake.
What happens on the day
Once we’re on site, we compare the joints with what we discussed. If anything is different, we explain it before carrying on. After that, the work takes a few hours to a few days, depending on the length of joint and the access. In Merton Abbey, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- Each joint is checked and the colour of the new sealant agreed.
- Failed sealant is removed back to clean, sound faces.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- We prime the faces where required.
- We gun in low-modulus sealant and tool it neatly.
How to prepare
- Keep children and pets away from the work area
- Let us know about earlier repairs to the joints
- Where the joints are inside, avoid wetting them before we arrive
Getting a quote
We don’t publish a price list. Instead, your job gets its own clear quote. To get started, call 0345 464 0079 or email us.