West Sussex · England
Three Bridges External Mastic
External mastic across Three Bridges and nearby, with every bit of old sealant taken out first and a 12-month guarantee.
- Sealant that has lost its bond to the brick or render
- Brick movement joints where the sealant has split
- Water getting into walls through failed joints
How the job changes by surface
Copings and trims
Coping joints that leak let water straight down into the wall. Sealing them early saves the wall below.
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 if the joint can be cleared.
External mastic for homes and businesses in Three Bridges
A movement joint is a deliberate break that lets a wall expand and contract. Its sealant has to flex with the building, season after season, so once it splits or hardens, the joint stops working and water gets in. We work on façade panels, copings & trims and joints between brick and frames, and common reasons people get in touch are damp patches traced to an open external joint and rigid filler in a joint that should flex.
Outbuildings, garages and conservatories around homes in places like Three Bridges add more joints to look after. Gutter ends, garage door frames and the joints where an extension meets the house are typical spots for leaks.
Your job is guaranteed for a year, as with all our work.
- Where
- Three Bridges (RH10)
- Wider area
- West Sussex
- Guarantee
- One year on every job
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
What affects the cost of external mastic
Your quote is based on your job. We look at:
- The product the joint needs
- How much old sealant there is and how hard it is to remove
- How many rooms, windows or areas are involved
- Whether the work is at height
The cost depends on the amount of work, how hard the old material is to remove and access to the work. We give a clear quote before work begins.
Helping us quote
The more you tell us, the more accurate the quote. When you get in contact, it helps to mention:
- A few pictures by email, if you can
- Any access issues, like height or stairs
- Whether it has been sealed before
- What the problem is, such as mould, gaps, leaks or cracking
There’s no standard price list, as no two jobs are quite the same. Instead, we send you a clear quote for your job. To get started, call 0345 464 0079 or email us.
Keeping the joints in good condition
Looking after new joints is easy, and it makes a real difference:
- Get split or bare joints resealed while the damage is small
- Keep movement joints as flexible joints, not mortar
- Deal with leaking gutters that soak the joints below
- Avoid pressure-washing directly into sealant joints
Avoid pressure-washing straight into the joints. A strong jet can damage the edges of the bead.
Water getting behind cladding or render can go unnoticed for a long time. When it finally shows inside, the joint may have been open for years.
What we can’t put right
We’d rather tell you now than do work that will not last, so these are the limits:
- Cracking across the wall rather than at a joint
- Render that’s blown, hollow or coming away
- Damp that is not coming from the joint
If you’re not sure, just call 0345 464 0079 or email us and we’ll give you a straight answer before you book.
Surfaces we seal
- Copings & trims
- Brickwork movement joints
- Joints between brick and frames
- Render & cladding joints
- Concrete & block
- Façade panels
Leave it or put it right?
Water gets in through a failed movement joint. Dealing with it early keeps the repair to the joint, rather than the wall around it. Homes in smaller places like Three Bridges can face more weather, and failed outside joints let damp into walls. Inside, a split seal lets water into floors and panels just as it would anywhere.
What you pay reflects the work, not guesswork. That’s why we ask about the job first.
Why choose Mr Mastic in Three Bridges
- Neat joints and a tidy finish
- 4.9 on Google from 180+ five-star reviews
- Trusted Arbo and Everbuild sealants
- One-year guarantee on every job
See our cost guide and what customers say.
Three Bridges: your questions answered
Do you cover smaller places like Three Bridges?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Do you work for landlords with property near Three Bridges station?
Yes, landlords and agents are among the people we work for, and several properties can go on one quote. You can call 0345 464 0079 or email us with the details for a clear quote.
Do you work at height?
Each building is different. Send us pictures and a rough idea of the height and we will confirm how they can be reached safely.
Is there a guarantee?
Yes, for a year. If there’s a problem with our work in that time, tell us and we’ll put it right.
What do you need from me for a quote?
Just the basics: the address or postcode, what’s wrong and any access issues. Then ring 0345 464 0079 or email us.
How do I get a quote for external mastic in Three Bridges?
The cost depends on the size of the job, access and how much old sealant has to come out. Call for a quick quote.
Can you do several jobs on one visit?
Yes. Tell us about everything you’d like done and you will get one quote.
Do you have insurance?
Yes. Mr Mastic is fully insured, with over 20 years’ experience in sealant work.
What happens on the day
We bring everything the job needs with us, so there’s nothing for you to buy. Once we’ve agreed what’s being done, we protect the area and start. Most jobs take a few hours to a few days, depending on the length of joint and the access. For a job in Three Bridges, 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 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.
- We prime the faces where required.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Preparing for the visit
- Where the joints are inside, avoid wetting them before we arrive
- Keep children and pets away from the work area
- Clear items away from the joints we are working on
Get a quote
We quote each job on its own, so the first step is telling us about yours. Just phone 0345 464 0079 or drop us an email with the details.
Advice
Places near Three Bridges
What else we do in Three Bridges
Outside joints around Three Bridges
Three Bridges is part of Crawley, one of the post-war new towns. Many homes date from the post-war decades and were built in phases, so neighbouring houses often have rooflines and wall joints of the same age, wearing out at the same time. Historic houses like Gravetye Manor (about 4.9 miles south-east) are a reminder that the area around Three Bridges 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.
If you live in an older home near St Barnabas', an extension built onto an older house moves differently, and the joint between them takes the strain. For site and facilities teams at buildings such as Pound Hill Junior School, movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. If you let a flat or house near Three Bridges station, split movement joints are easy to miss on a rental until damp shows inside.
Three Bridges is about 1 mile east of Crawley, in West Sussex. We provide external mastic to homeowners, landlords and businesses in Three Bridges and the surrounding area, as part of our work across West Sussex. Our area takes in 371 places across West Sussex, from the larger towns to small villages.
All of RH10 is within our area for external mastic, from the main roads to the quietest streets. You will find streets such as Ash Road, Mill Road and North Road, and we cover them all. Other places close to Three Bridges include Pound Hill (1 mile north-east), Worth (1 mile south-east), Maidenbower (1 mile south-east), Tilgate (1 mile south-west) and Crawley (1 mile west). We also work in nearby towns such as Horsham (8 miles south-west), Haywards Heath (9 miles south), Burgess Hill (11 miles south), East Grinstead (7 miles east), Billingshurst (14 miles south-west) and Bewbush (3 miles west).
Landmarks near Three Bridges
Around Three Bridges, our work takes us to homes and buildings near Hazelwick School, Central Sussex College and Grattons Park. There’s a railway station in Three Bridges itself: Three Bridges station. Other landmarks nearby include Crawley Hospital (1.6 miles west) and Crawley Museum (1.2 miles west). Green spaces nearby include Tilgate Lake.
For landlords and businesses
For anyone letting property in or around Three Bridges, several properties can go on one quote. Just tell us the addresses and what each one needs.
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.