Greater London · England
External & façade joints in Chislehurst, Greater London
External mastic across Chislehurst and nearby, with every bit of old sealant taken out first.
- Movement joints filled with mortar instead of sealant
- Failed seals between different materials
- Sealant pulling away from one side of the joint
DIY sealant or a professional job?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
External mastic for homes and businesses in Chislehurst
As ARBOMaster approved applicators, we choose exterior sealants to suit the joint and the surfaces. Some surfaces need a primer before sealing and we use one wherever it does. If you have failed sealant between panels on a façade and moss and dirt in joints with no sealant left, we can help.
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 Chislehurst, it’s worth checking who is responsible for the outside before booking.
You are covered for a year from the day we finish. If anything isn’t right with it, call 0345 464 0079 or email us.
- Place
- Chislehurst (BR7, BR1, BR2, SE9)
- Wider area
- Greater London
- Cover
- One year on every job
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
The process
The work is kept neat and contained to the area we’re working on, so you can get on with your day. The job usually takes a few hours to a few days, depending on the length of joint and the access, and we tell you how long to leave it before we go. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Chislehurst. It helps if you can point us to a visitor permit or a bay close to the door.
- Each joint is checked and the colour of the new sealant agreed.
- Failed sealant is removed back to clean, sound faces.
- Backing rod goes in so the sealant can stretch between the two faces.
- Primer is applied wherever the sealant needs it.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
How to prepare
- Let us know about earlier repairs to the joints
- For indoor joints, keep the area dry beforehand if you can
- Mention any parking rules near the property
Ask for a quote
Want a quote for external mastic? Please ring 0345 464 0079 or send us an email and tell us about the job. We’ll explain what we’d do and send you a clear quote before any work starts.
Advice
Chislehurst: your questions answered
Do you cover Chislehurst for external mastic?
Yes. Our work covers London and the South East, and Chislehurst is part of that. You can phone 0345 464 0079 or email us and tell us what needs doing.
Do you work for landlords with property near Chislehurst station?
Yes, rental work is part of what we do. You can phone 0345 464 0079 or send us an email with the address and a few details, and we’ll give you a fixed price before any work starts.
Can I add another job to the visit?
Yes. Just list everything you need and you’ll get one quote.
Are you an approved applicator?
Yes. We’re ARBOMaster approved, the scheme for applicators of Arbo sealants.
Is it worth trying it myself?
Some simple jobs can be done by a careful DIYer. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
What should I tell you?
The location, the problem and the rough size of the job. If you can, email a few pictures.
Are you fully insured?
Yes. Mr Mastic is fully insured.
Which products do you use?
It depends on the joint: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. Brands we use include Arbo and Everbuild.
External mastic in Chislehurst: local notes
With historic houses such as Bromley Palace (about 2 miles south-west) nearby, there’s older building stock in the area around Chislehurst as well as newer homes. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth. Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Letting a property close to Chislehurst station? Then outside joints that have cracked can let damp into a rental, so check them between lets. In the older streets around Parish Church The Annunciation Of Blessed Virgin Mary, an extension built onto an older house moves differently, and the joint between them takes the strain. As a London address, Chislehurst can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Chislehurst is about 3 miles north-west of Orpington, in Greater London. Homes, rented property, offices and hotels in Chislehurst can book us for external mastic, old or new, large or small. Every job comes with our one-year guarantee. Chislehurst is one of 764 towns and villages in Greater London where we work for external mastic. There’s also a page for London, roughly 9 miles from Chislehurst.
Here we cover the BR7, BR1, BR2 and SE9 postcode area for external mastic. If you need external mastic at a property on Chislehurst High Street, Sanderson Square and Wilderness Road or a nearby road, our applicators can take on the job. With the A208 and B264 close by, Chislehurst is simple for us to get to for external mastic. If you’re just outside Chislehurst, we cover Elmstead (1 mile west), Foxbury (1 mile east), Bickley (1 mile south-west), Widmore (1 mile south-west) and Coldharbour (1 mile north-west). Within a short drive, we also cover London (9 miles north-west), City of Westminster (12 miles north-west), Marylebone (12 miles north-west), Kensington (13 miles north-west), St Pancras (11 miles north-west) and Shoreditch (10 miles north-west).
Local landmarks in Chislehurst
We work in homes and buildings around The Queens Head pub, Coopers School and Chislehurst Common, among other places. Chislehurst’s nearest station is Chislehurst station, roughly 0.7 miles south-west. Other landmarks nearby include The Glades (2.2 miles west) and Queen Mary's Hospital (1.6 miles east). Green spaces nearby include The Tarn and Summer Hill.
What we can’t put right
New sealant can’t fix everything, and we’d rather say so up front. Sealant will not put right:
- Damp that isn’t coming from the joint
- Cracks in the bricks or render themselves, away from the joints
- Render that’s blown, hollow or coming away
If in doubt, ring 0345 464 0079 or email us and we will say what we think before booking.
What we seal
- Joints between brick and frames
- Copings & trims
- Façade panels
- Brickwork movement joints
- Render & cladding joints
- Concrete & block
Landlords, agents and businesses in Chislehurst
Failed sealant is one of the commonest items on a check-out report, and it’s easy to sort out between tenants. We can quote for more than one property at once.
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements and we’ll quote.
Why deal with it now?
A failed movement joint lets water into the wall, behind render and cladding. Resealing early keeps the job to the joint itself, rather than the wall around it. In London conversions, one flat’s bathroom is often above another flat’s ceiling, so a small leak from tired sealant can mean a neighbour’s ceiling and a lot of disruption. Dealing with it early is far simpler for homes in Chislehurst.
Rather than a set price list, we look at what your job involves: the amount of work, the old material and the access. The price is agreed before we begin.
What you get with us
- We never seal over old sealant
- Full insurance on every job
- Tidy, careful work
- 12-month guarantee on every job
Take a look at what affects the cost and customer reviews.
What the job involves on each surface
Copings and trims
Copings expand and contract through the day, so the joints need a sealant that stays flexible year round.
Brickwork movement joints
Brick movement joints are often mistaken for a missing mortar line. If that’s happened, we rake it out and reseal it properly if the joint can be cleared.
Other services in Chislehurst
How we quote for external mastic
Every job gets its own quote. This is what makes a difference:
- Any working-time requirements on site
- How much old sealant there is and how hard it is to remove
- The number of rooms or windows
- Access and height
Commercial jobs are quoted on the same basis as homes: how much there is to do, how we reach it and what it needs, along with when we can work on site. Ask us for a quote and we will go through it with you.
Helping us quote
When you call or email, it’s useful to know:
- The type of property
- Whether it has been sealed before
- Where the property is
- What’s wrong with the joints now
It all starts with a short chat. Describe the problem, the location and the size of the job, and we will talk you through what we’d do. When it suits you, ring 0345 464 0079 or drop us an email.