Kent · England
External Mastic in Borough Green
Movement joints in Borough Green need attention? We cut out the old, prepare the joints and apply the right sealant, with a 12-month guarantee.
- Movement joints with cracked, split or missing sealant
- Gaps where render, brick and frames meet
- Movement joints filled with mortar instead of sealant
How we handle external mastic in Borough Green
As ARBOMaster approved applicators, we choose exterior sealants to suit the joint and the surfaces. Porous or awkward surfaces are primed where the sealant needs it and we use one wherever it does. If you are dealing with movement joints filled with mortar instead of sealant and movement joints with cracked, split or missing sealant, we can put it right, whatever the surface.
Outbuildings, garages and conservatories around homes in places like Borough Green add more joints to look after. Leaks normally start at a gutter end, a garage door frame or where an extension meets the house.
The work is covered for a year after we finish. If anything isn’t right with it, ring 0345 464 0079 or send us an email.
- Location
- Borough Green (TN15)
- Region
- Kent
- Guarantee
- A year, on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
How the visit works
When we get to you, we check the joints match what you told us. If we find something unexpected, we talk it through with you first. After that, the work takes anything from a few hours to several days, depending on the building. For a job in Borough Green, we agree the time, the access and parking before the day. Outdoor jobs depend on a dry day, since sealant needs a dry surface.
- We start by checking each joint, agreeing the ones to redo and how we’ll reach them.
- The old mastic and anything lodged in the joint is removed.
- 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.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
Getting ready for the visit
- Plan for the work area to be out of bounds to pets and children
- Let us know about parking restrictions
- Try not to wet indoor joints just before the visit
Getting a quote
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints, and add photos by email if you can.
Read more
Borough Green questions
Do you cover smaller places like Borough Green?
Yes, we do. Our work covers London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
Can you help a landlord with a rental near Borough Green & Wrotham station?
Yes, rental work is part of what we do. Just ring 0345 464 0079 or send us an email and tell us about the property, and we will give you a clear price.
Can you seal joints between two different materials?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. We pick a colour that works with both materials.
What colours does the sealant come in?
We aim for a joint that suits the wall rather than one that jumps out. Colour is agreed with you before we begin from the range available.
Does someone need to be in?
We need access to the joints, so we’ll agree that with you when we book. For inside work, that normally means someone being in.
Can new sealant go over the old?
No, it will not last. It can look neat for a few weeks, but the new bead soon lifts. Removing the old sealant completely is the only lasting way.
What is backing rod for?
Closed-cell backing rod sets the depth of the sealant and stops it sticking to the back of the joint. Then the sealant bonds to two faces and can move.
Where are you based?
Our base is in Crawley, West Sussex, and we cover South East England, London and all of Scotland.
Places near Borough Green
More services for Borough Green
What we cannot put right
We won’t take on work that won’t last, so these are the limits:
- Cracks in the bricks or render themselves, away from the joints
- Subsidence or other structural problems
- Render that is blown, hollow or coming away
If you’re not sure, just ring 0345 464 0079 or drop us an email and we will give you a straight answer before you book.
Joints and surfaces we work on
- Brickwork movement joints
- Concrete & block
- Copings & trims
- Render & cladding joints
- Joints between brick and frames
- Façade panels
DIY versus a professional finish
If you are set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
Borough Green buildings and the weather
With historic houses such as Old Soar Manor (about 2.1 miles south) nearby, there’s older building stock in the area around Borough Green 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.
If you look after a building such as Borough Green Primary School, its movement joints, gutters and trims need looking after like any other building’s. For an older house near a landmark such as The Church of the Good Shepherd, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
Borough Green is about 5 miles east of Sevenoaks, in Kent. We provide external mastic to homes and businesses in Borough Green and the surrounding area, as part of our work across Kent. Borough Green is one of 922 towns and villages in Kent we cover for external mastic. For nearby work, see our London page, about 23 miles away.
Every address in TN15 is covered for external mastic, from the main roads to the quietest streets. External mastic is available to properties on Station Road, High Street and Hill View. If you’re just outside Borough Green, we cover Basted (1 mile south), Platt (1 mile east), Crouch (1 mile south), Claygate Cross (1 mile south) and Comp (1 mile east). Larger places within reach include Maidstone (10 miles east), Dartford (11 miles north), Sevenoaks (5 miles west), Royal Tunbridge Wells (11 miles south), Gravesend (10 miles north) and Tonbridge (7 miles south).
Near you in Borough Green
In Borough Green, that means homes and buildings near Wrotham School, Red Lion Public House and Wrotham School and the streets around them. Borough Green has its own railway station: Borough Green & Wrotham station. Well-known places in the area include Ightham Court (0.9 miles west) and Sevenoaks Hospital (4.9 miles west).
What the job involves on each surface
Copings and trims
Copings expand and contract through the day, so a flexible sealant suits them best year round.
Cladding and façade panels
Metal and composite panels move a lot with temperature, so the joints work hard every day. We choose the product to suit.
Aftercare tips
How long the joints last depends on use and care. We suggest:
- Fix overflowing gutters above sealed joints
- Check the sealant is paintable before painting near it
- Keep soil, plants and ivy away from the joints
- Tell anyone working on the walls about the movement joints
Keep pressure washers away from the sealant. High-pressure water can lift the edges and let water in behind.
Act while the splits are small. At that stage it’s a simple cut out and reseal with no damage behind it to deal with.
Signs you need external mastic in Borough Green
Sometimes a movement joint was filled with mortar or a rigid filler by mistake. The joint can’t move, so the wall cracks somewhere else instead.
If you can see any of these, it’s time to have the joints looked at:
- Old sealant gone brittle and cracked
- Cracked joints where brick meets render or frames
- Leaking joints around cladding and façade panels
- Damp patches traced to an open external joint
Rented homes near Borough Green & Wrotham station change hands often, and split movement joints are easy to miss on a rental until damp shows inside.
What to look for in a quote
- Whether the sealant suits the joint
- What happens if they find a problem under the old sealant
- Whether you can choose the colour
- How the joint is cleaned and prepared
How we quote for external mastic
Your quote is based on your job. We look at:
- Which sealant suits the joint
- The size of the job
- Mould in or behind the old joints
- Access and height
Doing several joints on one visit normally makes better use of the time than several visits, so it’s worth mentioning everything you’d like done. We will give you a clear quote for the lot.
Asking for a quote
A few details help us give you an accurate quote. When you get in contact, it helps to mention:
- Whether it has been sealed before
- A few pictures by email, if you can
- What’s wrong with the joints now
- How we’d reach the joints
Quotes start with a quick conversation. Describe the problem, the location and the size of the job. Whenever you’re ready, phone 0345 464 0079 or email us.