Kent · England
Stonehill Green External Mastic
Sealing brickwork movement joints, render, cladding and façade joints for householders, landlords and businesses in Stonehill Green. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Weeds or debris growing in open joints
- Weathered mastic that no longer stretches
- Damp patches traced to an open external joint
Leave it or put it right?
The longer a joint stays open, the more water the wall takes in. Wet masonry is more easily damaged by frost, so the problem grows beyond the joint itself. Older cottages and farmhouses around Stonehill Green can have timber floors and frames, where water from a failed joint can cause rot if it’s left.
Every job is a little different, so we quote each one individually. The number of joints, how easy they are to reach and the sealant needed all play a part.
Why Stonehill Green customers choose us
- ARBOMaster approved applicator
- Over 20 years’ experience
- Anti-fungal sanitary silicone in wet areas
- Full insurance on every job
Take a look at our cost guide or what customers say.
How we handle external mastic in Stonehill Green
Low-level joints can generally be done from the ground. Where joints are higher up, tell us about the building when you get in touch and we will confirm what access is needed. If you’re dealing with cracked joints where brick meets render or frames and plants rooting in failed movement joints, we can put it right, on façade panels, brickwork movement joints and copings & trims alike.
Somewhere as small as Stonehill Green, homes and farm buildings often face open ground, where walls and rooflines take the weather head on. Gutter joints and wall joints there need a sealant that can flex and stay put.
There’s a 12-month guarantee on every job.
- Location
- Stonehill Green (DA2)
- Wider area
- Kent
- Cover
- A year, on every job
- Quote
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Also near Stonehill Green
Also in Stonehill Green
Quotes for external mastic in Stonehill Green
We quote each job individually. These are the things that affect it:
- The old material and how stubborn it is
- Access and height
- How much there is to do
- Which sealant suits the joint
Homes and businesses are quoted the same way: the amount of work, the access and the products needed, plus any working-time requirements on site. Ask us for a quote and we will explain what it covers.
What we need to know
The more you tell us, the more accurate the quote. When you ask for a quote, tell us:
- Any previous sealing or DIY work
- Roughly how big the job is
- The problem you’ve noticed
- How we’d reach the joints
To get a quote, call 0345 464 0079 or drop us an email with the location and a short description of the problem. You’ll have a clear quote before we start.
What the job involves on each surface
Cladding and façade panels
Panel systems often rely on sealant between and around the panels. We reseal them with a sealant suited to the panel material.
Copings and trims
Coping joints that leak let water straight down into the wall. Sealing them early saves the wall below.
Stonehill Green questions
Do you cover smaller places like Stonehill Green?
Yes, we do. We work across London and the South East, and smaller places are part of that. The journey is planned ahead, so it helps to know about access.
Do you work for landlords with property near Swanley station?
Yes. We work for letting agents and landlords as well as homeowners, and several properties can go on one quote. You can call 0345 464 0079 or send us an email with the details for a clear quote.
Are you an approved applicator?
Yes. We hold ARBOMaster approved applicator status, and we’re fully insured.
Do you use backing rod?
Backing rod controls the sealant depth and keeps it off the back of the joint. Then the sealant bonds to two faces and can move.
Where is Mr Mastic based?
Our base is Crawley, with over 20 years’ experience. We work across South East England, London and Scotland.
Will there be a smell?
There can be a smell while the sealant cures, which fades as it sets. Opening a window helps.
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. We use products from Arbo and Everbuild.
Does someone need to be in?
It depends on the job. For work indoors, someone needs to let us in, and for outside work we will agree access with you when we book.
How to look after the new joints
Once the sealant has cured, a few habits help it last:
- Show decorators and builders where the movement joints are
- Check external joints each spring
- Leave the joints unpainted unless we’ve said otherwise
- Have failed joints looked at early
Give the sealant the cure time we tell you before anything rubs against it. Most exterior sealants skin fast but take longer to cure right through.
Small splits are the time to act. Then it’s a straightforward cut-out and reseal before water has had years to get in.
Walls and rooflines in Stonehill Green
Historic houses like Hall Place and Gardens (about 2.4 miles north) are a reminder that the area around Stonehill Green has older buildings as well as new. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Schools such as Hextable School are buildings too, and its movement joints, gutters and trims need looking after like any other building’s. Homes close to St Peter include some older properties, and old and new materials meet at the roofline and walls, which is where sealant earns its keep. If you let a flat or house near Swanley station, split movement joints are easy to miss on a rental until damp shows inside.
Stonehill Green is about 3 miles south-east of Sidcup, in Kent. We provide external mastic to householders, landlords and businesses in Stonehill Green, as part of our work across Kent. Stonehill Green is one of 922 towns and villages in Kent where we work. You can also see our page for London, about 13 miles away.
We cover every part of the DA2 postcode area for external mastic and the streets around it. Close by, we work in Puddledock (1 mile north-east), Hextable (1 mile east), Joyden's Wood (1 mile north), Hockenden (1 mile south-west) and Upper Ruxley (1 mile west). Within a short drive, we also cover Dartford (3 miles north-east), Sevenoaks (9 miles south), Gravesend (9 miles east), Northfleet (8 miles east), Kings Hill (14 miles south-east) and Swanscombe (6 miles north-east).
Local landmarks in Stonehill Green
Around Stonehill Green, our work takes us to homes and buildings near The Ship pub, Hextable Primary School and Dartford Heath and the streets around them. For rail, the closest station is Swanley station, about 1.4 miles south. Well-known places in the area include Queen Mary's Hospital (2.8 miles west) and Eynsford Castle (3.6 miles south-east). Green spaces nearby include Summer Hill and The Warren.
Landlord and commercial work in Stonehill Green
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.
Hotels need rooms back in use, so the work can be planned room by room. Hotel work is part of what we do, alongside homes and businesses.
DIY sealant or a professional job?
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
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.
What happens on the day
On the day, there’s very little for you to do. Point us to the joints and we’ll get on with it. The job generally takes anything from a few hours to several days, depending on the building. For a village or hamlet like Stonehill Green, the journey is planned in advance: tell us about narrow lanes, gates, long drives and where we can park. Everything for the job comes with us, so a second trip is avoided where possible.
- We inspect the joints and agree which need resealing and how they’ll be reached.
- We cut out the failed sealant and rake out any dirt or growth.
- We clean both faces of the joint and prime them where the product calls for it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Getting ready for the visit
- On commercial sites, let us know about site rules
- Where the joints are inside, avoid wetting them before we arrive
- Keep children and pets away from the work area
Getting a quote
Getting a quote is simple: let us know what needs doing and where, and roughly how big it is. Photos by email help us understand the job.