West Sussex · England
External Mastic in Thorney Island
Problem with your movement joints in Thorney Island? We cut out the old, prepare the joints and apply the right sealant, with a 12-month guarantee.
- Water getting into walls through failed joints
- Movement joints filled with mortar instead of sealant
- Failed sealant between panels on a façade
FAQs for Thorney Island
Do you cover smaller places like Thorney Island?
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 Southbourne station?
Yes, we work for landlords and letting agents. Just ring 0345 464 0079 or email us and tell us about the property, and we’ll give you a clear quote.
What colours does the sealant come in?
We aim for a joint that suits the wall rather than one that jumps out. We will talk through colour options before we start from the range available.
When is the sealant fully cured?
Cure times vary by product and the conditions. We tell you how long to leave it before we go.
Do I have to be there?
It depends on the job. For work indoors, someone needs to let us in, and for outside work we will agree access with you when we book.
Is it messy?
No. We protect the surfaces around the joints, and we clear up the old sealant and our materials before we leave.
Is it worth trying it myself?
It depends on the job. High-level, external movement and fire-rated joints are professional jobs, while a short indoor joint may be within reach.
How much does external mastic cost in Thorney Island?
Every job is different, so each one gets its own quote. To get one, phone 0345 464 0079 or drop us an email and let us know what needs doing and where.
How we handle external mastic in Thorney Island
We cut out failed sealant, set the joint depth with closed-cell backing rod and reseal with a low-modulus exterior sealant. The colour is chosen to suit the brick or render. Typical jobs include joints pointed up with cement by mistake and panel joints letting water in, on brickwork movement joints, concrete & block and joints between brick and frames.
Around Thorney Island, older buildings can be stone, brick or timber-framed, many with extensions added later. Where one material meets another is where water usually gets in, and they need the right sealant at the right depth.
We guarantee the work for a year. If something is not right with it in that time, tell us and we’ll put it right.
- Place
- Thorney Island (PO10)
- Region
- West Sussex
- Guarantee
- A year, on every job
- Quote
- A clear price before work begins
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
What affects the cost of external mastic
Jobs vary more than people expect. The main factors:
- Mould in or behind the old joints
- The product the joint needs
- Access and height
- How many rooms, windows or areas are involved
What you pay reflects the work, not a rough estimate. That is why we ask a few questions first and give you a clear price before work begins.
What to tell us for a quote
The more you tell us, the more accurate the quote. When you ask for a quote, tell us:
- Access, such as stairs, a lift or height
- The rough size of the job
- The problem you’ve noticed
- If it’s domestic, commercial or a hotel
There’s no standard price list. Instead, your job gets its own clear quote. To get started, phone 0345 464 0079 or email us.
Also near Thorney Island
More services for Thorney Island
Why it’s worth doing now in Thorney Island
A low-modulus sealant is chosen because it moves without pulling hard at the edges. That protects surfaces like brick, render and concrete. A stiffer product can damage the joint edge as it fails. Around Thorney Island, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
Doing several joints on one visit normally makes better use of the time than several visits, so tell us about everything that needs sealing. We’ll give you a clear price for the lot.
Why book with us
- Colour picked to suit the job
- Experience in homes, commercial sites and hotels
- 20+ years of sealant experience
- Fully insured
Take a look at what affects the cost and customer reviews.
DIY versus a professional finish
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Sealing over old silicone is the commonest DIY error. 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.
How the visit works
Most of a good job is in the preparation, and we don’t rush it. Every joint is cleaned and dried before new material goes in. All told, the work takes anything from a few hours to several days, depending on the building. Somewhere like Thorney Island needs a little journey planning: let us know about lanes, gates and parking. Everything for the job comes with us, so a second trip is avoided where possible.
- We start by walking round the building and agreeing the joints and the access.
- We cut out the old mastic and rake out anything in the joint.
- 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
- Mention any sign-in or site rules at work premises
- Move anything stored near the joints
- Plan for the work area to be out of bounds to pets and children
Ask for a quote
If you’re in Thorney Island and need external mastic, ring 0345 464 0079 or send us an email. Tell us what the problem is and where, and we’ll agree the price before any work begins.
Related advice
What we can’t put right
Some problems need a builder, plumber or other trade rather than us:
- Walls that need new movement joints cut into them
- Damp that isn’t coming from the joint
- Structural movement, which needs a surveyor or engineer
If in doubt, phone 0345 464 0079 or email us and we’ll say what we think before you book.
Surfaces we seal
- Concrete & block
- Joints between brick and frames
- Copings & trims
- Façade panels
- Render & cladding joints
- Brickwork movement joints
What external mastic looks like in Thorney Island
Thorney Island is close to the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. That is hard on movement joints and outside wall joints, especially on the side facing the sea. With historic houses such as Warblington Castle (about 2.1 miles north-west) nearby, there’s older building stock in the area around Thorney Island 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.
For landlords with property near Southbourne station, failed wall and movement joints let damp in, so they’re worth checking between tenancies. If you live in an older home near The Parish Church of St Nicholas, old and new materials meet at the roofline and walls, which is where sealant earns its keep. If you look after a building such as Thorney Island Community Primary School, its movement joints, gutters and trims need looking after like any other building’s.
Thorney Island is about 4 miles south-east of Havant, in West Sussex. If you need external mastic in Thorney Island, please phone 0345 464 0079 or drop us an email for a quick quote. We cover West Sussex from our Crawley base. Across West Sussex, we cover 371 places, and Thorney Island is one of them. Our Portsmouth page covers work nearby (7 miles or so).
Jobs for external mastic in PO10 is quoted and booked the same way as anywhere else. Streets in the area include Hunter Road, Emsworth Road and Spartan Close. Neighbouring places we cover for external mastic include West Thorney (1 mile south-east), North Hayling (1 mile west), Tye (1 mile south-west), Northney (1 mile west) and Emsworth (2 miles north). Within a short drive, we also cover Bognor Regis (11 miles east), Chichester (7 miles east), Selsey (9 miles south-east), Portfield (7 miles east), Yapton (14 miles east) and East Wittering (5 miles south-east).
Near you in Thorney Island
We work in homes and buildings around Bourne Community College and Eames Farm. The closest station to Thorney Island is Southbourne station, roughly 1.8 miles north-east of the centre. A little further out are Havant War Memorial Hospital (3.2 miles north-west) and Emsworth Museum (1.6 miles north). Not far away are Nutborne Marshes.
Looking after it afterwards
How long the joints last depends on use and care. We suggest:
- Have failed joints looked at early
- Clear growth from the base of walls and joints
- Wash walls gently around the sealant
- Look over the joints every year, ideally after winter
If you have more work done on the wall, such as new render, cladding or an opening, show the contractor the movement joints. They should be kept open and resealed, not filled.
Water getting behind cladding or render can go unnoticed for a long time. By the time there’s a damp patch, the damage can be well established so early resealing is worth it.
Work for landlords, hotels and businesses
Whether it’s one flat or a portfolio, the work is the same standard: the old material taken out, careful preparation and a 12-month guarantee.
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.