Greater London · England
External & façade joints in Charlton, Greater London
Professional external mastic in and around Charlton, with old sealant always removed completely and a 12-month guarantee.
- Moss and dirt in joints with no sealant left
- Weathered mastic that no longer stretches
- Leaking joints around cladding and façade panels
External mastic in Charlton
We’re ARBOMaster approved applicators, and each external joint gets a sealant suited to it. Some surfaces need a primer before sealing and we use one wherever it does. If you have sealant that has lost its bond to the brick or render and movement joints filled with mortar instead of sealant, we can put it right, whatever the surface.
Working on the outside of a London home means planning access: shared paths, upper floors and parking. In Charlton, joints up high may need ladders or other access, which is worth talking through when you book.
The work is guaranteed for twelve months. If there’s a problem with our work within the year, let us know and we will sort it.
- Place
- Charlton (SE7, SE18)
- Region
- Greater London
- Guarantee
- A year, on every job
- Quote
- A clear price before we start
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Leave it or put it right?
Resealing a run of joints in one go is usually better than patching one at a time. Joints of the same age tend to fail together. 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.
Homes and businesses are quoted the same way: the amount of work, the access and the products needed, plus any working-time requirements on site. Call for a quick quote and we’ll explain what it covers.
Why book with us
- Colour picked to suit the job
- White, clear, grey or another colour, product permitting
- More than 20 years in sealant work
- Sanitary silicone with an anti-fungal additive in wet areas
Take a look at our cost guide and our reviews.
How it works
On the day, we start by going over the job with you, so there are no surprises. Surfaces next to the work are protected before work begins. The work usually takes anything from a few hours to several days, depending on the building. In Charlton, 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.
- Backing rod goes in so the sealant can stretch between the two faces.
- We prime the faces where required.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Before we arrive
- Tell us if parking is tricky
- For business premises, tell us about site rules or sign-in
- Try not to wet indoor joints just before the visit
How to get a quote
Getting a quote is simple: let us know the job and the location, and roughly how big it is. A few photos by email make the job easier to understand, and we’ll come back to you with a quote.
Read more
How to look after the new joints
Once the sealant has cured, a few habits help it last:
- Avoid pressure-washing directly into sealant joints
- Never let anyone fill a movement joint with mortar
- Walk round the building once a year and look at the joints
- Keep soil, plants and ivy away from the joints
Follow the cure time we give you before the joint is knocked or disturbed. Most exterior sealants skin fast but take longer to cure right through.
Gaps, plants or missing sealant in a joint are worth getting looked at. Earlier resealing means a smaller job and a better result.
Questions from Charlton
Do you work for landlords with property near Charlton station?
Yes. We work for landlords and letting agents as well as homeowners, and several properties can go on one quote. You can call 0345 464 0079 or email us with the details for a clear quote.
Is Charlton in your area for external mastic?
Yes. We work across London and the South East, and Charlton is part of that. Just call 0345 464 0079 or drop us an email with a few details of the job.
Can a movement joint be filled with mortar?
No. A mortar-filled joint can’t move, so the movement cracks the wall elsewhere. Use a flexible sealant with backing rod.
Where do you work from?
We’re based in Crawley, and we cover South East England, London and all of Scotland.
Can you seal over the old sealant?
No. Fresh sealant does not stick to old sealant, and it traps any mould or water underneath. It all has to come out first.
Do I have to be there?
For indoor joints, yes, someone needs to let us in. After that, you can carry on with your day.
Can you do several jobs on one visit?
Yes. Just list everything you need.
When is the sealant fully cured?
Most sealants are touch-dry well before they’re fully cured. We will give you the cure time for the product we used before we leave.
How we quote for external mastic
You will get a clear quote before work begins. It takes into account:
- Whether the work is at height
- Which sealant suits the joint
- How many areas need sealing
- How much old sealant there is and how hard it is to remove
Instead of a standard rate, we look at what your job involves: the amount of work, the old material and the access. You will know the price before we begin.
What we need to know
You don’t need to know the technical terms. Just tell us:
- How many joints, rooms or windows are involved
- Whether it’s a home or a business
- Whether it has been sealed before
- Pictures of the joints, sent by email
For a quick quote, get us on the phone, or send an email if you’d rather. Tell us about the joints that need doing and we’ll explain what’s involved.
What sealant work cannot fix
In fairness, there are a few things sealant will not fix:
- Cracked brickwork or render that needs a builder or plasterer
- Damp that isn’t coming from the joint
- Cutting new joints into brickwork, which is building work rather than sealant work
If you are not sure, just ring 0345 464 0079 or send us an email and we will give you a straight answer before booking.
Joints and surfaces we work on
- Joints between brick and frames
- Render & cladding joints
- Brickwork movement joints
- Façade panels
- Concrete & block
- Copings & trims
Should I try it myself first?
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
Walls and rooflines in Charlton
London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. With historic houses such as Queen's House (about 1.9 miles west) nearby, there’s older building stock in the area around Charlton 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.
As a London address, Charlton can be tricky for parking: let us know about parking bays, permits or a driveway. For landlords with property near Charlton station, split movement joints are easy to miss on a rental until damp shows inside. Schools such as Thorntree Primary School are buildings too, and larger buildings have long runs of movement joint that eventually need resealing.
Charlton is about 2 miles west of Plumstead, in Greater London. Wherever you are in the SE7 postcode area, our applicators can take on external mastic. Charlton is one of 764 places in Greater London where we work for external mastic. London is on our list too, about 6 miles from Charlton.
Here we cover the SE7 and SE18 postcode area for external mastic. Streets in the area include Floyd Road, Guild Road and Priolo Road, all of which we cover. We also cover New Charlton (1 mile north-west), Westcombe Park (1 mile west), Woolwich (1 mile east), Vanbrugh Park Estate (1 mile south-west) and Kidbrooke (2 miles south). Within a short drive, we also cover London (6 miles west), City of Westminster (8 miles west), Marylebone (8 miles west), Kensington (10 miles west), St Pancras (7 miles west) and Shoreditch (6 miles north-west).
Local landmarks in Charlton
Around Charlton, our work takes us to homes and buildings near Charlton Park, Wildwood Montessori School and Royal Greenwich Trust School. Charlton has its own railway station: Charlton station. A little further out are British Hospital for Mothers and Babies (0.5 miles east) and Gallions Reach Shopping Park (2.3 miles north-east). Open spaces near Charlton include Gilbert's Pit.
Towns and villages near Charlton
What else we do in Charlton
What the job involves on each surface
Cladding and façade panels
Panels heat up and cool down quickly, so the joints work hard every day. We choose the product to suit.
Brickwork movement joints
Brick moves with heat and moisture, and grows a little over time. That movement goes into the joint, so its sealant has to stay flexible.