Greater London · England
External & façade joints in Old Coulsdon, Greater London
Sealing brickwork movement joints, render, cladding and façade joints for householders, landlords and businesses in Old Coulsdon. ARBOMaster approved applicators, fully insured, with a 12-month guarantee.
- Weathered mastic that no longer stretches
- Failed sealant between panels on a façade
- Brick movement joints where the sealant has split
How we handle external mastic in Old Coulsdon
Low-level joints can usually be done from the ground. Where joints are higher up, tell us about the building when you get in touch and we’ll confirm what’s needed to reach them safely. We work on concrete & block, façade panels and copings & trims, and common reasons people get in touch are cracked joints where brick meets render or frames and leaking joints around cladding and façade panels.
Newer London blocks are built with movement joints in brick and render, and with cladding joints sealed with mastic. Older terraces have their own weak points: gutter joints, roofline trims and the joint where an extension meets the original wall.
All of our work is guaranteed for twelve months.
- Where
- Old Coulsdon (CR5, CR3, CR8)
- Wider area
- Greater London
- Cover
- One year on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Updated
- 26 October 2026
What we are called out for in Old Coulsdon
Sometimes a movement joint was filled with mortar or a rigid filler, often by someone who didn’t know what it was for. With the joint locked solid, the movement turns into cracks elsewhere in the wall.
Look out for any of the following:
- Movement joints filled with mortar instead of sealant
- Joints with sealant missing in places
- Joints where the bead has come unstuck
- Moss and dirt in joints with no sealant left
As a London address, Old Coulsdon can be tricky for parking: let us know about parking bays, permits or a driveway.
Before you book anyone
- What preparation is included
- What happens if they find a problem under the old sealant
- Who turns up on the day
- When the joint can take water or movement
Also near Old Coulsdon
More services for Old Coulsdon
What happens on the day
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 any work begins. The work usually takes a few hours for a handful of joints, longer for a whole elevation. In a London area like Old Coulsdon, the main things to plan are parking and access: tell us about permits, visitor bays or off-street space, which floor we’re working on and whether there’s a lift.
- First we look over the joints with you, agree which to renew and talk through access.
- The old mastic and anything lodged in the joint is removed.
- Both sides are cleaned back to sound material and primed if needed.
- Backing rod goes in next, setting the depth and keeping the sealant off the back of the joint.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
How to prepare
- Clear items away from the joints we are working on
- Mention if the joints have been sealed before
- Tell us if parking is tricky
Ask for a quote
Want a quote for external mastic? Please phone 0345 464 0079 or send us an email with a few details. You’ll know what we plan to do, and what it will cost, before any work begins.
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Aftercare tips
No joint lasts for ever, but care makes a real difference. A few tips:
- Check external joints each spring
- Keep water from gutters off the wall
- Keep soil, plants and ivy away from the joints
- Have failed joints looked at early
Do not let soil, plants or ivy build up against the new joints. Damp material against the sealant shortens its life.
Small splits are the time to act. Then it’s a straightforward cut-out and reseal with no damage behind it to deal with.
Landlord and commercial work in Old Coulsdon
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance that we can handle for you.
Letting agents often deal with us directly. Tell us the address, the job and how access works and we’ll give you a quote.
Leave it or put it right?
Resealing a run of joints in one go is normally better than patching one at a time. Joints of the same age tend to fail together, and access only has to be arranged once. In a London flat, a failed joint rarely stays your problem alone: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
Some things make a job bigger or smaller: the old material and how easily it comes out, whether mould needs treating, and whether the work is at height. We take all of that into account in your quote.
Why choose Mr Mastic in Old Coulsdon
- Old sealant always removed completely
- We leave the area clean and tidy
- Domestic, commercial and hotel work
- More than 20 years in sealant work
Read our cost guide or customer reviews.
FAQs for Old Coulsdon
Is Old Coulsdon in your area for external mastic?
Yes. We work across London and the South East, and Old Coulsdon is part of that. Just call 0345 464 0079 or drop us an email with a few details of the job.
Is parking an issue for external mastic in Old Coulsdon?
Parking in Old Coulsdon, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly.
How long will you be here?
A typical job takes a few hours to a few days, depending on the length of joint and the access, including preparation and clearing up. We’ll confirm how long when we quote.
Why do you put foam in the joint first?
We fit closed-cell backing rod wherever the joint depth needs controlling. It controls the depth and stops the sealant bonding to the back.
Do you take out the old sealant first?
Always. Sealing over old sealant is the main reason resealing fails early, and it’s something we never do.
Can you match the colour of my brickwork?
There’s a good range of exterior colours, including greys, browns, whites and stone tones. We pick the one that suits your wall best so the joint doesn’t draw the eye.
Do I need to be at home?
Access is agreed with you when the job is booked. Indoors, that usually means someone at home.
How long should I leave it?
That depends on the sealant used, so please follow the time we give you.
DIY sealant or a professional job?
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
A DIY attempt does not rule out a professional job. We cut it out and start again.
Outside joints around Old Coulsdon
Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. In terraces and conversions, gutters and walls are often shared with the neighbours, so check who is responsible for the outside before booking.
Schools such as Keston Primary School are buildings too, and movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. Homes close to Church of St John the Evangelist include some older properties, and older walls, gutters and the joints where extensions meet them need a flexible sealant.
Old Coulsdon is about 1 mile south-east of Coulsdon, in Greater London. From the centre of Old Coulsdon to the outskirts, external mastic is available for homes and businesses alike, from flats and houses to offices and hotels. Our Greater London coverage runs to 764 places, Old Coulsdon among them. Our London page covers work nearby, about 14 miles away.
All of CR5, CR3 and CR8 is covered for external mastic. Whether your property is on Ellis Road, Tollers Lane and Court Avenue or anywhere close by, we can help. We also cover the places around Old Coulsdon: Coulsdon (1 mile north-west), Chipstead (2 miles west), Purley (2 miles north), Woodcote (2 miles north-west) and Woodmansterne (3 miles west). We also work in nearby towns such as London (14 miles north), City of Westminster (15 miles north), Marylebone (15 miles north), Kensington (14 miles north), Whitechapel (15 miles north) and Brompton (14 miles north).
Local landmarks in Old Coulsdon
Typical jobs here are in homes near Sunnydown School, Dollypers Hill and The Tudor Rose pub. For rail, the closest station is Coulsdon South station, about 1.4 miles north-west of the centre. Other landmarks nearby include East Surrey Museum (2 miles south-east) and St Lawrence's Hospital (1.3 miles south-east). Open spaces near Old Coulsdon include Nore Hill and Mercers Lake.
Different surfaces, different methods
Cladding and façade panels
Where a cladding system has its own specified sealant, we follow it or an approved alternative. Send us any details you have about the façade.
Concrete and blockwork
Concrete and block walls shrink as they dry and move with temperature. Their movement joints are sealed over backing rod with a flexible sealant.