West Sussex · England
External Mastic in Southbourne
Movement joints in Southbourne 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
- Old sealant gone brittle and cracked
- Rain getting behind render or cladding at a joint
External mastic in Southbourne, done properly
Ground-floor and low-level joints are straightforward to reach. Where joints are higher up, tell us about the building when you get in touch and we will confirm what’s needed to reach them safely. If you have weeds or debris growing in open joints and water getting into walls through failed joints, we can help, on concrete & block, render & cladding joints and copings & trims alike.
Houses in smaller places like Southbourne can stand more in the open than those in a built-up town, and walls and rooflines facing the weather take the worst of it. Joints on those sides are generally the first to go.
The work is covered for a year after we finish. If there’s a problem with it, please call 0345 464 0079 or send us an email.
- Where
- Southbourne (PO10)
- Region
- West Sussex
- Cover
- 12 months on all our work
- Quotes
- A clear price before we start
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
How the job changes by surface
Copings and trims
Coping joints that leak let water straight down into the wall. Resealing them is a small job that protects a lot.
Joints between dissimilar materials
Where a frame or panel meets masonry, water often finds a way in. We cut out the old sealant and reseal with a product suited to both surfaces.
Common problems we fix in Southbourne
Sometimes a movement joint was filled with mortar or a rigid filler by mistake. The joint cannot move, so the wall cracks somewhere else instead.
Look out for these signs:
- Sealant that has lost its bond to the brick or render
- Hard, crazed mastic that has stopped moving
- Water getting into walls through failed joints
- Brick movement joints where the sealant has split
If you live in an older home near St. John's, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
Before booking anyone
- Whether all the old sealant comes out first
- What insurance they hold
- What happens if the job turns out different
- Is VAT in the price?
What we cannot put right
New sealant can’t fix everything, and we’d rather say so up front. It will not solve:
- Cracking across the wall rather than at a joint
- Failed render or damaged cladding panels
- Damp that is not coming from the joint
If in doubt, call 0345 464 0079 or drop us an email and we will say what we think.
Joints and surfaces we work on
- Concrete & block
- Brickwork movement joints
- Render & cladding joints
- Façade panels
- Copings & trims
- Joints between brick and frames
FAQs for Southbourne
Can you help a landlord with a rental near Southbourne station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. Just phone 0345 464 0079 or email us with the address and what needs doing, and we’ll give you a clear price.
Does the coastal weather in Southbourne affect outside sealant?
Near the coast, wind-driven rain and, nearer the shore, salt air make outside sealant work harder. The right product, a clean joint and the right depth all help it cope.
Do you work in Southbourne?
Yes. We cover Southbourne. For a quote, call 0345 464 0079 or drop us an email.
Do you use backing rod?
We fit closed-cell backing rod wherever the joint depth needs controlling. It sets the sealant depth and prevents three-sided bonding.
How do you reach high-level joints?
That depends on how high the joints are and the ground below. Ground-floor joints are simple; for higher ones, send details and we’ll confirm the access.
Should I point up the gap in my brickwork?
No. Mortar locks the joint solid, so the movement cracks the wall elsewhere. Use a flexible sealant with backing rod.
When will the joints need doing again?
It varies from wall to wall: sunny, exposed elevations and busy joints wear faster. A yearly look will tell you when they need doing. Our work comes with a one-year guarantee.
Can I add another job to the visit?
Yes, we can. More than one area can be quoted together.
Walls and rooflines in Southbourne
Southbourne is close to the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. Both are hard on movement joints and outside wall joints, which can dry out and crack sooner where a building faces the weather. Historic houses like Warblington Castle (about 2.5 miles west) are a reminder that the area around Southbourne 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.
Rented homes near Southbourne station change hands often, and failed wall and movement joints let damp in, so they’re worth checking between tenancies. For site and facilities teams at buildings such as Southbourne Junior School, its movement joints, gutters and trims need looking after like any other building’s.
Southbourne is about 4 miles east of Havant, in West Sussex. Wherever you are in the PO10 postcode area, we can carry out external mastic at your property. Our area takes in 371 places across West Sussex, large and small. There’s also a page for Portsmouth, about 8 miles away.
Postcode districts we cover here for external mastic: PO10. Whether your property is on Lodgebury Close, Manor Road and Northcote Gardens or a nearby road, our applicators can take on the job. Neighbouring places we cover for external mastic include Woodmancote (1 mile north), Lumley (1 mile west), Westbourne (1 mile north-west), Emsworth (1 mile west) and Thorney Island (2 miles south-west). Larger places within reach include Bognor Regis (11 miles south-east), Chichester (6 miles east), Selsey (10 miles south-east), Portfield (6 miles east), Yapton (13 miles east) and East Wittering (6 miles south).
Landmarks near Southbourne
Around Southbourne, our work takes us to homes and buildings near The Traveller's Joy Public House, Eames Farm and Bourne Community College. There’s a railway station in Southbourne itself: Southbourne station. Well-known places in the area include Warblington Castle (2.5 miles west) and Emsworth Museum (1.3 miles west). Open spaces near Southbourne include Stoke Down and Brook Meadow (Emsworth).
Why it’s worth doing now in Southbourne
Done well, a resealed joint is a neat, straight line that suits the wall. A rushed bead with no backing looks untidy and does not last. In a smaller place like Southbourne, wherever a wall is exposed, a failed outside joint is a real source of damp. Inside, a split seal lets water into floors and panels just as it would anywhere.
A few things move the cost up or down: the old material and how easily it comes out, any mould to treat, and whether the work is at height. We take all of that into account in your quote.
Why Southbourne clients choose us
- Colour picked to suit the job
- We leave the area clean and tidy
- 4.9 on Google from 180+ five-star reviews
- We agree the colour with you first
Read our cost guide and our reviews.
DIY sealant or a professional job?
If you’ve already had a go yourself, that is fine. We cut it out and start again, so just mention it when you contact us.
The biggest DIY mistake is sealing over old sealant. New silicone won’t bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
Aftercare tips
No joint lasts for ever, but care makes a real difference. Our tips:
- Deal with leaking gutters that soak the joints below
- Make sure movement joints aren’t pointed over
- Walk round the building once a year and look at the joints
- Get split or bare joints resealed while the damage is small
Follow the cure time we give you before the joint is knocked or disturbed. The surface skins over quickly, but full cure takes longer.
Once a joint cannot move, the wall finds another way, often as cracks near the joint. Resealing it early helps prevent that.
Places near Southbourne
What else we do in Southbourne
How the visit works
There is not much for you to do on the day. Show us the job and we’ll take it from there. The work itself takes a few hours for a handful of joints, longer for a whole elevation, including the tidy-up. Parking around Southbourne is usually easier than in a town centre, but mention any lanes, gates or long drives. For outside work, side access and the height of the joints help us plan.
- We look at every joint and agree a colour to suit the wall.
- We take out the old sealant until the faces are sound.
- 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.
Getting ready for the visit
- Where the joints are inside, avoid wetting them before we arrive
- For business premises, tell us about site rules or sign-in
- Keep pets and children clear of the area while we work
Ask for a quote
We quote each job on its own, so the first step is telling us about yours. Just ring 0345 464 0079 or send us an email with the details.