Surrey · England
External Mastic in Box Hill
Sealing brickwork movement joints, render, cladding and façade joints for homeowners, landlords and businesses in Box Hill. Fully insured, ARBOMaster approved and guaranteed for a year.
- Rigid filler in a joint that should flex
- Panel joints letting water in
- Weathered mastic that no longer stretches
Box Hill buildings and the weather
The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. Historic houses like Polesden Lacey (about 3.9 miles west) are a reminder that the area around Box Hill has older buildings as well as new. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material.
Managing a site like The Ashcombe School? Then movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. If you live in an older home near St. Andrew's Church, an extension built onto an older house moves differently, and the joint between them takes the strain. Letting a property close to Betchworth station? Then outside joints that have cracked can let damp into a rental, so check them between lets.
Box Hill is about 2 miles north-east of Dorking, in Surrey. We provide external mastic to homes and businesses in Box Hill and the surrounding area, as part of our work across Surrey. We cover 395 towns and villages across Surrey, from the larger towns to small villages. We also work in Crawley, about 11 miles from Box Hill.
All of KT20 is covered for external mastic. We cover properties on Boxhill Road, Usherwood Close and Fort Road and the roads around them. Neighbouring places we cover for external mastic include Betchworth (1 mile south-east), Brockham (1 mile south), Buckland (1 mile south-east), Strood Green (2 miles south) and Headley (2 miles north). Within a short drive, we also cover Guildford (12 miles west), Woking (13 miles west), Epsom (6 miles north), Horley (7 miles south-east), Redhill (5 miles east) and Ewell (7 miles north).
Near you in Box Hill
Typical jobs here are in homes near Brockham Limeworks, among other places. The closest station to Box Hill is Betchworth station, roughly 0.8 miles east. A little further out are Headley Court (2.8 miles north) and Reigate Priory Museum (3.6 miles east). The countryside around Box Hill includes Colley Hill and Reigate Heath.
How we handle external mastic in Box Hill
Many failed façade joints only get noticed once there’s a stain or a damp patch inside. We inspect them, agree which need doing and reseal with a weatherproof, flexible sealant. If you have movement joints filled with mortar instead of sealant and sealant pulling away from one side of the joint, we can help, whatever the surface.
Older homes in small places like Box Hill may be stone, brick or timber-framed, often with later extensions. The joints where those materials meet are the weak points, and they need the right sealant at the right depth.
The work is covered for a year after we finish. If anything is not right with it, ring 0345 464 0079 or send us an email.
- Location
- Box Hill (KT20)
- Wider area
- Surrey
- Guarantee
- One year on every job
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Your questions about external mastic in Box Hill
Do you work for landlords with property near Betchworth station?
Yes, rental work is part of what we do. Just ring 0345 464 0079 or email us and tell us about the property, and we will send you a clear quote.
Do you cover smaller places like Box Hill?
Yes, Box Hill is covered. Our work covers London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
Do you do commercial work?
Yes, regularly. We can plan bigger jobs in stages.
Will the new joint stand out?
We aim for a joint that suits the wall rather than one that jumps out. Colour is agreed with you before we begin, matched as closely as the range allows.
Which products do you use?
Quality sealants from brands including Arbo and Everbuild, picked for each joint. We will tell you what we’re using and why.
Do you hold any approvals?
Yes. Mr Mastic is an ARBOMaster approved applicator, and we’re fully insured.
Can new sealant go over the old?
No, because it fails. We remove every bit of old sealant first, so the new sealant bonds properly.
How long does external mastic last?
It varies with how exposed the wall is and how much the joint moves. Signs to watch for are cracking, hardening and gaps at the edges, and reseal at that point.
DIY sealant or a professional job?
Sealing over old silicone is the commonest DIY error. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Nearby places to Box Hill
More services for Box Hill
How it works
You do not need to clear the whole room or building, just the space around the work. We protect the rest, and the work takes anything from a few hours to several days, depending on the building in most cases. For a village or hamlet like Box Hill, 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 look at every joint and agree a colour to suit the wall.
- Failed sealant is removed back to clean, sound faces.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- Primer is applied wherever the sealant needs it.
- We gun in low-modulus sealant and tool it neatly.
Preparing for the visit
- Mention any leaks or damp you’ve noticed
- For business premises, tell us about site rules or sign-in
- Let us know about earlier repairs to the joints
How to get a quote
For external mastic in Box Hill, ring 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and you will get a clear quote before any work starts.
Read more
Aftercare tips
Joint life depends on how it’s used and looked after. We suggest:
- Get split or bare joints resealed while the damage is small
- Don’t let climbing plants root in the sealant
- Tell anyone working on the walls about the movement joints
- Check external joints each spring
Only paint over the joint if we have confirmed the sealant can take paint. Many exterior sealants are not designed to be painted, and paint can crack as the joint moves.
Leave a failed movement joint and water keeps getting into the wall. That can lead to damp patches, staining and frost damage which cost more to put right than the joint.
Landlords, agents and businesses in Box Hill
Mouldy or split sealant often shows up at the end of a tenancy, and it’s quick to put right between tenancies. Several properties can go on one quote.
We work for landlords and agents as well as householders. Resealing between tenancies keeps a property looking cared for.
What affects the cost of external mastic
We do not publish a price list, because jobs vary so much. The quote depends on:
- Any mould that needs treating
- The old material and how stubborn it is
- Which sealant suits the joint
- How many rooms, windows or areas are involved
Commercial jobs are quoted on the same basis as homes: the amount of work, the access and the products needed, along with when we can work on site. Ask us for a quote and we’ll explain what it covers.
Asking for a quote
There’s no need for technical detail. It helps if you can tell us:
- Where the property is
- Any access issues, like height or stairs
- What’s wrong with the joints now
- If someone has resealed it before
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is, and we will explain how we’d tackle it. When it suits you, ring 0345 464 0079 or send us an email.
When something else is needed
A few problems are outside what sealant work can do:
- Structural movement, which needs a surveyor or engineer
- Adding movement joints to masonry that has none
- Rising or penetrating damp from elsewhere in the wall
If in doubt, ring 0345 464 0079 or drop us an email and we will say what we think before booking.
What we seal
- Brickwork movement joints
- Joints between brick and frames
- Copings & trims
- Façade panels
- Concrete & block
- Render & cladding joints
Why it’s worth doing now in Box Hill
The longer a joint stays open, the more water the wall takes in. In cold weather, frost can damage wet brick and render, so the problem grows beyond the joint itself. Older cottages and farmhouses around Box Hill can have timber floors and frames, and water through a failed joint can rot timber if it’s left.
Some things make a job bigger or smaller: how much old sealant there is and how stubborn it is, any mould to treat, and whether we need extra access for height. Your quote takes all of that into account.
Why us?
- We are fully insured
- Neat joints and a tidy finish
- A choice of colours where the product allows
- You choose the colour before work begins
Take a look at what affects the cost or what customers say.