Greater London · England
External Mastic in Hither Green
Movement joints in Hither Green need attention? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Leaking joints around cladding and façade panels
- Gaps where render, brick and frames meet
- Movement joints with cracked, split or missing sealant
Do you need external mastic in Hither Green?
Sometimes a movement joint was filled with mortar or a rigid filler. The joint cannot move, so the wall cracks somewhere else instead.
The most common problems we see are:
- Old sealant gone brittle and cracked
- Leaking joints around cladding and façade panels
- Sealant that has lost its bond to the brick or render
- Movement joints filled with mortar instead of sealant
Hither Green is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book.
Questions to ask before booking
- What product goes in the joint
- How the colour is chosen
- How long to leave it before use
- What preparation is included
External mastic in Hither Green, 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. Common call-outs are for water getting into walls through failed joints and panel joints letting water in, on concrete & block, render & cladding joints and brickwork movement joints.
In London terraces and converted houses, gutters and walls are often shared with the house next door, so a leaking gutter joint or failed wall joint can affect more than one home. For a flat in Hither Green, check the lease for who looks after the outside.
Each job carries a 12-month guarantee, whatever its size.
- Place
- Hither Green (SE13, SE12, SE6)
- Region
- Greater London
- Cover
- One year on every job
- Quotes
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Walls and rooflines in Hither Green
London terraces and converted houses often share gutters, downpipes and walls, so check who is responsible for the outside before booking. Historic houses like Queen's House (about 2 miles north) are a reminder that the area around Hither Green has older buildings as well as new. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material.
In the older streets around Church of St Swithun, the joints between older walls, newer extensions and the roofline need a sealant that can move. For landlords with property near Hither Green station, split movement joints are easy to miss on a rental until damp shows inside.
Hither Green is about 2 miles south-east of New Cross, in Greater London. From the centre of Hither Green to the outskirts, we cover external mastic for every kind of property, from flats and houses to offices and hotels. Our Greater London coverage runs to 764 places, Hither Green among them.
Work in SE13, SE12 and SE6 works the same way as everywhere else we cover. Local streets include Old Road, Manor Lane and Pascoe Road, and we cover them all. We also cover Lee (1 mile east), Ladywell (1 mile west), Lewisham (1 mile north-west), Catford (1 mile south-west) and Horn Park (1 mile east). Larger places within reach include London (5 miles north-west), City of Westminster (8 miles north-west), Marylebone (8 miles north-west), Kensington (9 miles west), St Pancras (7 miles north-west) and Shoreditch (6 miles north-west).
Around Hither Green
In Hither Green, that means homes and buildings near International Academy of Greenwich, The Edmund Halley pub and Manor House Gardens. There’s a railway station in Hither Green itself: Hither Green station. Well-known places in the area include Lewisham Shopping Centre (0.9 miles north-west) and University Hospital Lewisham (0.7 miles west). Open spaces near Hither Green include Brookmill Road Local Nature Reserve and Summer Hill.
Why act early in Hither Green
Mortar or ordinary filler might look like a quick way to close an open joint, but it stops the joint moving. The wall then cracks somewhere else. A flexible sealant over backing rod is what the joint needs. 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.
What you pay reflects the work, not guesswork. That’s why we ask a few questions first and give you a clear quote before we start.
Why book with us
- White, clear, grey or coloured to suit, where the product allows
- We agree the colour with you first
- Quality sealants from Arbo and Everbuild
- We are fully insured
See our cost guide and our reviews.
Your questions about external mastic in Hither Green
Is parking an issue for external mastic in Hither Green?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. That way the visit can be planned around it.
Do you work for landlords with property near Hither Green station?
Yes, landlords and agents are among the people we work for. Just phone 0345 464 0079 or email us with the address and what needs doing, and we’ll give you a clear price.
Will there be a smell?
It depends on the product. Some smell for a while, some hardly at all, and any smell fades as they cure.
How do I get a quote for external mastic in Hither Green?
Size, access and the old material all affect the cost. Call for a quick quote and we’ll talk you through it.
Is the work guaranteed?
Yes. Each job is guaranteed for twelve months, wherever you are.
Where are you based?
Our base is Crawley. We work across South East England, London and Scotland.
Can I do it myself?
Some simple jobs can be done by a careful DIYer. Most DIY failures come from sealing over old material, wet joints or too much sealant.
How long does external mastic last?
That depends on the wall, the weather and the movement. Signs to watch for are cracking, hardening and gaps at the edges and have them redone then.
DIY sealant or a professional job?
A DIY attempt doesn’t rule out a professional job. We cut it out and start again, so just mention it when you contact us.
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it peels away and traps moisture behind it. Everything old must be removed first.
The process
When we arrive, we look over the joints with you first, so you know exactly what we are doing. Surfaces next to the work are protected before work begins. The work normally takes a few hours for a handful of joints, longer for a whole elevation. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Hither Green. It helps if you can point us to a visitor permit or a bay close to the door.
- First we look over the joints with you, agree which to renew and talk through access.
- We cut out the failed sealant and rake out any dirt or growth.
- The joint faces are cleaned and primed where the sealant needs it.
- We push in closed-cell backing rod so the sealant is the right depth and bonds to the sides only.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Preparing for the visit
- Mention any sign-in or site rules at work premises
- Tell us about access, such as stairs, a lift or high-level joints
- Keep children and pets away from the work area
Getting a quote
Need a quote? Please ring 0345 464 0079 or drop us an email and tell us about the job. We’ll explain what we’d do and give you a clear quote before any work starts.
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What else we do in Hither Green
Quotes for external mastic in Hither Green
The price is agreed before any work begins. It takes into account:
- Any mould that needs treating
- How many areas need sealing
- Whether old sealant or filler has to be cut out
- The product the joint needs
There are no prices on our website, because the cost depends so much on the job itself. Call for a quick quote.
Helping us quote
When you call or email, these details help:
- The problem you’ve noticed
- How we’d reach the joints
- Any previous sealing or DIY work
- The type of property
For a quote, ring 0345 464 0079 or email us and tell us where the job is and what the problem looks like. You will have a clear quote before any work starts.
Different surfaces, different methods
Joints between dissimilar materials
Joints where frames, sills or panels meet the wall are common leak points. The old joint is removed and a sealant that bonds to both sides goes in.
Render joints
Water behind render can lead to blown patches. Resealing the joints early keeps water out and protects the render itself.
Landlords, agents and businesses in Hither Green
Hotels need rooms back in use, so the work can be planned room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.