Kent · England
Horns Green External Mastic
We cover Horns Green for sealing brickwork movement joints, render, cladding and façade joints. Old material cut out, joints cleaned and sealed neatly and a one-year guarantee.
- Weeds or debris growing in open joints
- Rain getting behind render or cladding at a joint
- Old sealant gone brittle and cracked
Horns Green questions
Do you work for landlords with property near Knockholt 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 work begins.
Can you do external mastic in Horns Green?
Yes. We work across London and the South East, and Horns Green is part of that. You can ring 0345 464 0079 or drop us an email and let us know what needs doing.
Why is there a gap in my brick wall?
A movement joint is a planned break in the wall that absorbs expansion and shrinkage. It should be filled with flexible sealant, never mortar.
What do you put in the joint?
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.
Do you work for hotels and businesses?
Yes. We can plan bigger jobs in stages to suit the site.
Can you match the colour of my brickwork?
We choose a sealant colour to suit the brick, stone or render so the joint blends in. Exterior sealants come in a good range of colours.
Can you reach joints on upper floors?
That depends on the building and the joints. Where joints can be reached safely, we’ll do them. Tell us about the building and we will confirm what access is needed.
Is there any odour?
Sometimes, a little. It fades as the sealant cures.
External mastic in Horns Green, done properly
Low-level joints can generally be done from the ground. For joints higher up, give us some details of the building and we will confirm what access is needed. Common call-outs are for weathered mastic that no longer stretches and leaking joints around cladding and façade panels, on brickwork movement joints, façade panels and copings & trims.
External sealant needs dry, clean surfaces, so work around Horns Green is planned for dry weather. Tell us about access to all sides of the building, including outbuildings and garages.
Each job carries a 12-month guarantee, large or small.
- Where
- Horns Green (TN14)
- Region
- Kent
- Guarantee
- One year on every job
- Quotes
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Common problems we fix in Horns Green
Sunlight, wet weather and frost wear exterior sealant down. Over the years it hardens, cracks on the surface and loses its give, so the joint eventually tears or comes away from one side.
The problems people generally mention when they call are:
- Movement joints filled with mortar instead of sealant
- Weathered mastic that no longer stretches
- Panel joints letting water in
- Failed seals between different materials
For site and facilities teams at buildings such as Charles Darwin School, movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
Comparing quotes
- Which colour the sealant will be
- Is VAT in the price?
- The length of the guarantee
- How hidden problems are handled
Towns and villages near Horns Green
Also in Horns Green
Should I try it myself first?
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it fails, we can still redo it.
How the visit works
Once we’re on site, 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 for a handful of joints, longer for a whole elevation. Somewhere like Horns Green needs a little journey planning: let us know about lanes, gates and parking. We bring what the job needs, so it can be finished in one trip where possible.
- We start by walking round the building and agreeing the joints and the access.
- Every bit of old sealant and any mortar or debris is cut out.
- Joint faces are cleaned back and primed if the sealant needs it.
- We fit closed-cell backing rod to control the depth.
- The exterior sealant is applied, tooled and checked along its length.
Getting ready for the visit
- Tell us about access, such as stairs, a lift or high-level joints
- Mention if the joints have been sealed before
- Mention any sign-in or site rules at work premises
Getting a quote
To get a quote, call 0345 464 0079 or email us with the location and a short description of the problem. We’ll give you a clear price before any work starts.
Advice
Looking after it afterwards
No joint lasts for ever, but care makes a real difference. A few tips:
- Check the sealant is paintable before painting near it
- Have failed joints looked at early
- Check external joints each spring
- Don’t let climbing plants root in the sealant
Keep the joints clear of soil, plants and climbing growth. Anything that holds water against the joint wears it out sooner.
If you can see gaps, plants or bare sections in a joint, have it checked. Earlier resealing means a smaller job and a better result.
Work for landlords, hotels and businesses
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 and landlords in Horns Green can book us as well as homeowners. Sealant work between tenants keeps a property looking cared for before the next move-in.
Horns Green buildings and the weather
Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. With historic houses such as Down House (about 2.1 miles north-west) nearby, there’s older building stock in the area around Horns Green as well as newer homes. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material.
If you live in an older home near Church of St Peter and St Paul, old and new materials meet at the roofline and walls, which is where sealant earns its keep. Rented homes near Knockholt station change hands often, and outside joints that have cracked can let damp into a rental, so check them between lets.
Horns Green is about 5 miles west of Sevenoaks, in Kent. We carry out external mastic for homes and businesses in Horns Green and nearby, as part of our work across Kent. Our area takes in 922 places across Kent, large and small. We also work in London, about 15 miles from Horns Green.
Work in TN14 works the same way as everywhere else we cover. External mastic is available to properties on Cudham Lane South and Thrift Lane and the roads around them. We also cover Burlings (1 mile north-east), Cudham (1 mile north-west), Berry's Green (1 mile north-west), Single Street (1 mile north-west) and Aperfield (2 miles west). Larger places within reach include Dartford (11 miles north-east), Sevenoaks (5 miles east), Royal Tunbridge Wells (14 miles south-east), Gravesend (15 miles north-east), Tonbridge (11 miles south-east) and Northfleet (14 miles north-east).
Landmarks near Horns Green
Typical jobs here are in homes near The Blacksmith's Arms, among other places. Horns Green’s nearest station is Knockholt station, roughly 3.4 miles north-east of the centre. Well-known places in the area include Orpington Hospital (3.8 miles north). The countryside around Horns Green includes Downe Bank and Betsom's Hill.
How the job changes by surface
Concrete and blockwork
The face of concrete or block is often dusty, so preparation is key. We prime where the sealant needs it before sealing.
Brickwork movement joints
Brick movement joints are often mistaken for a missing mortar line. If that is happened, we rake it out and reseal it properly where it can be done safely.
When it isn’t the sealant
It helps to know what we cannot do:
- Damp that is not coming from the joint
- Movement that is more than a sealant joint can take
- Cracked brickwork or render that needs a builder or plasterer
If you are not sure, just call 0345 464 0079 or email us and we’ll give you a straight answer before you book.
What we seal
- Joints between brick and frames
- Concrete & block
- Copings & trims
- Brickwork movement joints
- Façade panels
- Render & cladding joints