Greater London · England
External Mastic in Orpington
External mastic in Orpington from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Rain getting behind render or cladding at a joint
- Plants rooting in failed movement joints
- Old sealant gone brittle and cracked
External mastic in Orpington, done properly
Where two different materials meet, such as brick and render or blockwork and metal, they move at different rates. A flexible exterior sealant takes up that movement. Typical jobs include movement joints filled with mortar instead of sealant and hard, crazed mastic that has stopped moving, on joints between brick and frames, brickwork movement joints and render & cladding 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. In a converted house in Orpington, it’s worth checking who is responsible for the outside before booking.
Whatever the size of the job, you get the same one-year guarantee.
- Location
- Orpington (BR5, BR6, BR7, DA14)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
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
- Clear growth from the base of walls and joints
- Keep movement joints as flexible joints, not mortar
- Act on the first splits you see
Follow the cure time we give you before the joint is knocked or disturbed. The surface skins over quickly, but full cure takes longer.
Leave a failed movement joint and water keeps getting into the wall. That can lead to damp patches, staining and frost damage which cost more to put right than the joint.
Do you need external mastic in Orpington?
Buildings move more than people expect. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. All of that ends up in the joint sealant.
These are the problems we are asked about most:
- Weathered mastic that no longer stretches
- Movement joints with cracked, split or missing sealant
- Leaking joints around cladding and façade panels
- Failed seals between different materials
For an older house near a landmark such as St Andrew's, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
Questions to ask before you book
- Are they insured?
- How much experience the applicator has
- How hidden problems are handled
- What product goes in the joint
Orpington buildings and the weather
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 Bromley Palace (about 3.8 miles west) nearby, there’s older building stock in the area around Orpington as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material.
Schools such as Perry Hall Primary School are buildings too, and larger buildings have long runs of movement joint that eventually need resealing. Letting a property close to St Mary Cray station? Then split movement joints are easy to miss on a rental until damp shows inside.
Orpington is about 12 miles south-east of London, in Greater London. If you need external mastic in Orpington, it’s easy to get a quote: please phone 0345 464 0079 or send us an email. We’re based in Crawley and cover Greater London. Across Greater London, we cover 764 places, Orpington among them. Our London page covers work nearby, about 12 miles away.
Jobs for external mastic in BR5, BR6, BR7 and DA14 works the same way as everywhere else we cover. That includes homes and businesses on High Street, Furzehill Square and Station Road and the roads around them. Being close to the A224 and B258, Orpington is easy for our applicators to reach. Nearby, we also carry out external mastic in Poverest (1 mile north), Derry Downs (1 mile east), St Mary Cray (1 mile north), St Paul's Cray (1 mile north) and Goddington (1 mile south). Larger places within reach include London (12 miles north-west), City of Westminster (14 miles north-west), Marylebone (14 miles north-west), Kensington (15 miles north-west), St Pancras (14 miles north-west) and Shoreditch (13 miles north-west).
What’s near Orpington
We work in homes and buildings around The Priory School, Jubilee Country Park and Harris Academy Orpington and the streets around them. The closest station to Orpington is St Mary Cray station, roughly 0.7 miles north of the centre. Well-known places in the area include Lullingstone Castle (4.4 miles south-east) and Orpington Hospital (1.5 miles south). Green spaces nearby include The Warren and Summer Hill.
Nearby places to Orpington
Also in Orpington
Surface by surface
Render joints
Render has movement joints and stop beads that need sealing. They’re resealed in a sealant that suits the render.
Brickwork movement joints
Brick movement joints are often mistaken for a missing mortar line. Where one has been mortared, we cut it out and reseal it with sealant.
When something else is needed
Honest advice matters more to us than a booking, so here’s what sealant cannot fix:
- Cracking across the wall rather than at a joint
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
- Cutting new joints into brickwork, which is building work rather than sealant work
If in doubt, phone 0345 464 0079 or send us an email and we’ll say what we think.
Surfaces we seal
- Joints between brick and frames
- Render & cladding joints
- Façade panels
- Copings & trims
- Brickwork movement joints
- Concrete & block
Work for landlords, hotels and businesses
Housing providers, facilities teams and property managers book us too. We can quote a run of properties together.
We work for letting agents and landlords as well as homeowners. Resealing between tenancies is a simple way to keep a property in good order.
What happens on the day
When we get to you, we check the joints match what you told us. 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. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. Mention any building rules, key holders or managing agents when you book.
- We inspect the joints and agree which need resealing and how they’ll be reached.
- 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.
- We gun in a flexible exterior sealant in a colour that suits the wall and tool it neatly.
Getting ready for the visit
- Try not to wet indoor joints just before the visit
- Mention any tricky access
- Keep pets and children clear of the area while we work
Ask for a quote
We do not publish a price list, as no two jobs are quite the same. Instead, we give you a clear price for your job. To arrange one, ring 0345 464 0079 or email us.
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Your questions about external mastic in Orpington
I let a flat near St Mary Cray station. Can you help?
Yes, landlords and agents are among the people we work for. You can ring 0345 464 0079 or drop us an email with the details for a clear quote.
Is parking a problem for a job in Orpington?
Parking in Orpington, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
When will the joints need doing again?
It depends on the exposure, the movement and the product. Treat it as a maintenance item and look at it yearly and renew it when it starts to fail.
How long will you be here?
It depends on the size of the job, but as a guide it takes a few hours to a few days, depending on the length of joint and the access. We will tell you when we quote.
Are you fully insured?
Yes. Full insurance covers our work, and we can confirm the details when we quote.
Is it worth trying 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.
Where is Mr Mastic based?
Our base is in Crawley, West Sussex, and we work across South East England, London and Scotland.
Can you do several jobs on one visit?
Yes, and it often makes sense. Doing several areas at once is usually more efficient.
Why deal with it now?
Mortar or ordinary filler might look like a quick way to close an open joint, but it locks the joint solid. The movement then cracks the brickwork or render nearby. The correct repair is a flexible sealant with the right backing. In a flat in Orpington, failed sealant seldom stays inside your own four walls: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
Commercial jobs are quoted on the same basis as homes: the amount of work, how we reach it and what it needs. Call for a quick quote and we’ll explain what it covers.
Why Orpington customers choose us
- We leave the area clean and tidy
- We never seal over old sealant
- A 12-month guarantee on all work
- Colour picked to suit the job
Take a look at how sealant jobs are priced and customer reviews.