Greater London · England
External & façade joints in Telegraph Hill, Greater London
Movement joints in Telegraph Hill need attention? We cut out the old, prepare the joints and apply the right sealant.
- Rigid filler in a joint that should flex
- Sealant pulling away from one side of the joint
- Leaking joints around cladding and façade panels
How the job changes by surface
Render joints
Rendered walls have joints at beads, openings and changes of material. We reseal them with a flexible exterior sealant that suits the render colour.
Brickwork movement joints
People sometimes point up a brick movement joint by mistake. Where one has been mortared, we cut it out and reseal it with sealant.
External mastic in Telegraph Hill, done properly
A movement joint is a deliberate break that lets a wall expand and contract. The sealant in it has to stretch and squeeze for years, so once it splits or hardens, the joint stops working and water gets in. We work on joints between brick and frames, copings & trims and render & cladding joints, and common reasons people get in touch are hard, crazed mastic that has stopped moving and damp patches traced to an open external joint.
Working on the outside of a London home means planning access: shared paths, upper floors and parking. For a home in Telegraph Hill, tell us how high the joints are and how to reach the back of the building.
All our work comes with a one-year guarantee, wherever you are in Greater London.
- Location
- Telegraph Hill (SE4, SE15, SE14)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
The process
We bring everything the job needs with us, so you don’t need to buy or prepare anything. After a quick look at the joints together, we protect the area and start. It normally takes a few hours for a handful of joints, longer for a whole elevation. In Telegraph Hill, as in most of London, parking needs a little planning. It helps if you can point us to a visitor permit or a bay close to the door.
- We start by checking each joint, agreeing the ones to redo and how we’ll reach them.
- 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
- Where the joints are inside, avoid wetting them before we arrive
- For business premises, tell us about site rules or sign-in
- Tell us if parking is tricky
Ask for a quote
For a quick quote, get us on the phone, or email us if that’s easier. Tell us about the joints that need doing and we’ll talk you through the work and send you a clear quote.
Read more
Why deal with it now?
The longer a joint stays open, the more water the wall takes in. In cold weather, frost can damage wet brick and render around the joint, so the damage spreads beyond the joint. 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.
Rather than a set price list, we price the job in front of us: the amount of work, the old material and the access. The price is agreed before we begin.
What you get with us
- You choose the colour before work begins
- Trusted Arbo and Everbuild sealants
- White, clear, grey or coloured to suit, where the product allows
- 180+ five-star Google reviews
When something else is needed
Honest advice matters more to us than a booking, so here’s what sealant can’t fix:
- Failed render or damaged cladding panels
- Cutting new joints into brickwork, which is building work rather than sealant work
- Rising or penetrating damp from elsewhere in the wall
If in doubt, call 0345 464 0079 or email us and we will say what we think before you book.
Joints and surfaces we work on
- Render & cladding joints
- Façade panels
- Brickwork movement joints
- Concrete & block
- Joints between brick and frames
- Copings & trims
Keeping the joints in good condition
No joint lasts for ever, but care makes a real difference. Our tips:
- Fix overflowing gutters above sealed joints
- Make sure movement joints aren’t pointed over
- Tell anyone working on the walls about the movement joints
- Leave the joints unpainted unless we have said otherwise
Follow the cure time we give you before the joint is knocked or disturbed. The surface skins over quickly, but full cure takes longer.
An open movement joint lets rain into the wall every time it pours. Over time it can mean damp inside, stained render or frost-damaged brick, all bigger jobs than a reseal.
Telegraph Hill buildings and the weather
Historic houses like Queen's House (about 2 miles north-east) are a reminder that the area around Telegraph Hill has older buildings as well as new. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
For an older house near a landmark such as St Catherine's Hatcham, older walls, gutters and the joints where extensions meet them need a flexible sealant. If you look after a building such as Haberdashers' Hatcham College, larger buildings have long runs of movement joint that eventually need resealing. Rented homes near Brockley station change hands often, and split movement joints are easy to miss on a rental until damp shows inside.
Telegraph Hill is about 1 mile south-west of New Cross, in Greater London. From the centre of Telegraph Hill to the outskirts, external mastic is available for homes and businesses alike. 764 places in Greater London are on our list, large and small.
Here we cover the SE4, SE15 and SE14 postcode area for external mastic. Streets in the area include Mona Road, Pepys Road and Kitto Road, all of which we cover. We also cover the places around Telegraph Hill: Nunhead (1 mile south-west), New Cross (1 mile north-east), Peckham (1 mile north-west), St Johns (1 mile east) and Brockley (1 mile south-east). We also work in nearby towns such as London (3 miles north-west), City of Westminster (6 miles north-west), Marylebone (6 miles north-west), Kensington (7 miles west), St Pancras (5 miles north-west) and Shoreditch (4 miles north).
Around Telegraph Hill
Typical jobs here are in homes near Fordham Park and The Brockley Barge pub. Telegraph Hill has its own railway station: Brockley station. Well-known places in the area include Southwark Adult Education Institute (0.6 miles north-west) and Lewisham Shopping Centre (1.4 miles east). Green spaces nearby include St. James's Park Lake and New Cross Gate Cutting.
Telegraph Hill questions
Do you cover Telegraph Hill for external mastic?
Yes, Telegraph Hill is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or email us and tell us what needs doing.
Do you work for landlords with property near Brockley station?
Yes, rental work is part of what we do. Just call 0345 464 0079 or email us and tell us about the property, and we will send you a clear quote.
Do you guarantee your work?
Yes. Each job is guaranteed for twelve months, large or small.
Can you quote for more than one area?
Yes. Just list everything you need.
Do you remove the old sealant?
Yes. Sealing over old sealant is the main reason resealing fails early, so we never do it.
Can you seal joints between render and window frames?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. We pick a colour that works with both materials.
What does external mastic cost?
The cost depends on the size of the job, access and how much old sealant has to come out. Call for a quick quote and we’ll talk you through it.
Do you do commercial work?
Yes, regularly. We can plan bigger jobs in stages to suit the site.
More services for Telegraph Hill
What affects the cost of external mastic
Some jobs are bigger than they look, and some smaller. The main factors:
- Whether the work is at height
- Any working-time requirements on site
- Whether there’s mould to deal with
- The type of sealant required
Every job is a little different, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all make a difference.
What we need to know
When you call or email, these details help:
- The problem you’ve noticed
- The rough size of the job
- If it’s domestic, commercial or a hotel
- If someone has resealed it before
Every job is quoted individually. Simply call 0345 464 0079 or drop us an email and describe the job.
Work for landlords, hotels and businesses
Mouldy or split sealant often shows up at the end of a tenancy, and it’s easy to sort out between tenants. We can quote for more than one property at once.
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements.