Greater London · England
Westcombe Park External Mastic
Movement joints in Westcombe Park need attention? We remove the old material, prepare the joints and seal them properly, with a one-year guarantee.
- Weeds or debris growing in open joints
- Rain getting behind render or cladding at a joint
- Cracked joints where brick meets render or frames
External mastic for homes and businesses in Westcombe Park
Low-level joints can usually be done from the ground. For joints higher up, give us some details of the building and we will confirm what access is needed. We work on render & cladding joints, joints between brick and frames and concrete & block, and common reasons people get in touch are joints pointed up with cement by mistake and panel joints letting water in.
London’s terraces and conversions often share walls, gutters and downpipes with their neighbours, so one failed joint can cause damp for more than one household. In a converted house in Westcombe Park, it’s worth checking who is responsible for the outside before booking.
All our work is covered by our one-year guarantee.
- Place
- Westcombe Park (SE10, SE7, SE3)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Quotes
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
The process
You don’t need to clear the whole room or building, only the area right around the joints. Everything nearby is protected, and the job takes a few hours for a handful of joints, longer for a whole elevation in most cases. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Westcombe Park. It helps if you can point us to a visitor permit or a bay close to the door.
- We look at every joint and agree a colour to suit the wall.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- We prime the faces where required.
- We gun in low-modulus sealant and tool it neatly.
Preparing for the visit
- On commercial sites, let us know about site rules
- Mention any tricky access
- Let us know about parking restrictions
Get a quote
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is, and we will explain how we’d tackle it. Whenever you are ready, phone 0345 464 0079 or email us.
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Leave it or put it right?
Pointing a movement joint with mortar might seem a neat fix, but it stops the joint moving. The wall then cracks somewhere else. A flexible sealant over backing rod is what the joint needs. In older London homes, water behind a failed joint soaks into brick and timber without much sign, and once it shows in Westcombe Park, the repair is bigger than a sealant job.
What you pay reflects the work, not guesswork. That is why we ask about the job first.
Why choose Mr Mastic in Westcombe Park
- Sealant colour chosen to suit
- 180+ five-star Google reviews
- We never seal over old sealant
- Quality sealants from Arbo and Everbuild
Take a look at what affects the cost and what customers say.
Do you need external mastic in Westcombe Park?
Joints sealed without backing rod, or far too deep, rarely last. Sealant bonded to three sides has nowhere to go and rips as the joint opens.
Look out for these signs:
- Failed sealant between panels on a façade
- Gaps where render, brick and frames meet
- Water getting into walls through failed joints
- Plants rooting in failed movement joints
Letting a property close to Westcombe Park station? Then split movement joints are easy to miss on a rental until damp shows inside.
What to look for in a quote
- Whether VAT is included
- Which colour the sealant will be
- Whether they’re fully insured
- Who does the work, and how experienced they are
Landlords, agents and businesses in Westcombe Park
We also work for property managers and facilities teams. We can quote a run of properties together, and we’re fully insured for the work.
Mouldy or split sealant often shows up at the end of a tenancy, and it’s quick to put right between tenancies. We can quote for more than one property at once.
DIY sealant or a professional job?
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Westcombe Park: your questions answered
Do you cover Westcombe Park for external mastic?
Yes. We work across London and the South East, and Westcombe Park is part of that. Just ring 0345 464 0079 or drop us an email with a few details of the job.
I let a flat near Westcombe Park station. Can you help?
Yes, we work for landlords and letting agents. Just ring 0345 464 0079 or email us and tell us about the property, and we’ll send you a clear quote.
What does external mastic cost?
It depends on the job, so we quote each one individually. To get one, call 0345 464 0079 or drop us an email with a short description of the job.
Is there a guarantee?
Yes: twelve months. If there’s a problem with our work in that time, tell us and we will put it right.
Can I do it myself?
That depends on the joint. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional, while a short indoor joint may be within reach.
How long does the job take?
That depends on the amount of work, but most jobs take anything from a few hours to several days, depending on the building. We will tell you when we quote.
Are you ARBOMaster approved?
Yes. We are approved under the ARBOMaster scheme, which is run for the Arbo sealant brand.
Should I point up the gap in my brickwork?
No, not where the gap is a movement joint. Filling it with mortar defeats its purpose. A flexible sealant is the right fill.
External mastic in Westcombe Park: local notes
London terraces and converted houses often share gutters, downpipes and walls, so it’s worth agreeing who is responsible before work starts. With historic houses such as Queen's House (about 1 mile west) nearby, there’s older building stock in the area around Westcombe Park as well as newer homes. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth.
Managing a site like Halstow Primary School? Then larger buildings have long runs of movement joint that eventually need resealing. Homes close to St George's Church include some older properties, and older walls, gutters and the joints where extensions meet them need a flexible sealant.
Westcombe Park is about 2 miles east of New Cross, in Greater London. From the centre of Westcombe Park to the outskirts, we cover external mastic for every kind of property. Across Greater London, we cover 764 places, and Westcombe Park is one of them.
We cover every part of the SE10, SE7 and SE3 postcode area for external mastic and the streets around it. External mastic is available to properties on Webb Road, Horn Lane and Hardy Road and the roads around them. We also cover the places around Westcombe Park: Vanbrugh Park Estate (1 mile south-west), Maze Hill (1 mile west), Greenwich (1 mile west), New Charlton (1 mile north-east) and Charlton (1 mile east). Within a short drive, we also cover London (5 miles west), City of Westminster (8 miles west), Marylebone (7 miles west), Kensington (10 miles west), St Pancras (7 miles north-west) and Shoreditch (5 miles north-west).
Landmarks near Westcombe Park
Locally, jobs take us to homes and businesses close to Blackheath High School, Wildwood Montessori School and East Greenwich Pleasaunce and the streets around them. Westcombe Park has its own railway station: Westcombe Park station. Well-known places in the area include Greenwich Castle (1 mile south-west) and Charlton Athletic Museum (0.8 miles east). For a walk, there’s Tower Hill and Gilbert's Pit.
Aftercare tips
To keep the joints looking good and working properly:
- Clear growth from the base of walls and joints
- Check external joints each spring
- Fix overflowing gutters above sealed joints
- Act on the first splits you see
Look over the joints once a year, ideally after winter. Watch for splits, edges coming away or growth in the joint.
A joint that has stopped moving pushes the movement elsewhere, often as cracks near the joint. Resealing it early helps prevent that.
What affects the quote in Westcombe Park
For a quick quote, just ask. The main things that affect it are:
- The number of rooms or windows
- How much old sealant there is and how hard it is to remove
- Which sealant suits the joint
- Any mould that needs treating
Doing several joints on one visit is normally more efficient than separate visits, so it’s worth mentioning everything you’d like done. We’ll give you a clear price for the lot.
Helping us quote
When you contact us, these details help:
- Whether it has been sealed before
- Where the job is, and your postcode
- The type of property
- Access, such as stairs, a lift or height
We quote each job on its own, so start by telling us what you need. Just ring 0345 464 0079 or email us with the details, and photos are welcome.