Hampshire · England
Swanwick External Mastic
Professional external mastic in and around Swanwick, with old sealant always removed completely and a 12-month guarantee.
- Joints where the bead has come unstuck
- Weathered mastic that no longer stretches
- Damp patches traced to an open external joint
What external mastic looks like in Swanwick
Swanwick is within about 3 miles of the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. That’s hard on movement joints and outside wall joints, especially on the side facing the sea. Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Managing a site like Sarisbury Church of England Junior School? Then its movement joints, gutters and trims need looking after like any other building’s. If you let a flat or house near Bursledon station, split movement joints are easy to miss on a rental until damp shows inside.
Swanwick is about 2 miles south of Hedge End, in Hampshire. From the centre of Swanwick to the outskirts, external mastic is available for homes and businesses alike. Our area takes in 683 places across Hampshire.
We cover every part of the SO31 and PO15 postcode area for external mastic. That includes homes and businesses on Walpole Lane, Ashby Mews and Swanwick Lane and the roads around them. We also cover Lower Swanwick (1 mile north-west), Sarisbury (1 mile south-east), Park Gate (1 mile south-east), Burridge (1 mile north-east) and Sarisbury Green (1 mile south). Larger places within reach include Winchester (12 miles north), Gosport (8 miles south-east), Havant (13 miles east), Eastleigh (6 miles north-west), Fareham (4 miles south-east) and Horndean (12 miles east).
What’s near Swanwick
We work in homes and buildings around The Old Ship Inn and Brookfield Community School and Language College. The nearest railway station is Bursledon station, roughly 0.8 miles west. Nearby you will also find Bursledon Brickworks Industrial Museum (within half a mile north) and St Andrew's Castle (2.4 miles south-west). Not far away are Swanwick Lakes.
External mastic for homes and businesses in Swanwick
Getting the depth right is half the job. Backing rod controls how deep the sealant goes and keeps it off the back of the joint, so it bonds to the two sides only and can stretch. We work on façade panels, copings & trims and joints between brick and frames, and common reasons people get in touch are cracked joints where brick meets render or frames and rigid filler in a joint that should flex.
External sealant needs dry, clean surfaces, so work around Swanwick is planned for dry weather. Tell us about access to all sides of the building, including outbuildings and garages.
The work is covered for a year after we finish. If anything is not right with it, phone 0345 464 0079 or drop us an email.
- Location
- Swanwick (SO31, PO15)
- Region
- Hampshire
- Guarantee
- A year, on every job
- Quote
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
What we can’t put right
Before you book, it’s worth knowing the limits too:
- Rising or penetrating damp from elsewhere in the wall
- Cracking across the wall rather than at a joint
- Walls that need new movement joints cut into them
If in doubt, call 0345 464 0079 or drop us an email and we’ll say what we think.
What we seal
- Copings & trims
- Render & cladding joints
- Façade panels
- Concrete & block
- Joints between brick and frames
- Brickwork movement joints
Different surfaces, different methods
Cladding and façade panels
Metal and composite panels move a lot with temperature, so the joint sealant has to cope with frequent movement. The sealant is chosen with that in mind.
Concrete and blockwork
Concrete faces can be dusty and porous, so preparation is key. A primer goes on where the product requires one before sealing.
How it works
When we get to you, we compare the joints with what we discussed. If anything is different, we explain it before carrying on. Most jobs then take a few hours to a few days, depending on the length of joint and the access. In a small place like Swanwick, access is normally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- 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.
- We apply the sealant, tool it and check the whole run.
Before we arrive
- Mention any parking rules near the property
- Clear the area around the work
- Let us know about earlier repairs to the joints
Ask for a quote
Need a quote? Please phone 0345 464 0079 or drop us an email with a few details. We will explain what we’d do and give you a clear price before work begins.
Advice
Towns and villages near Swanwick
Also in Swanwick
Aftercare tips
To keep the joints looking good and working properly:
- Fix overflowing gutters above sealed joints
- Check external joints each spring
- Do not let climbing plants root in the sealant
- Wash walls gently around the sealant
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.
Act while the splits are small. Then it’s a straightforward cut-out and reseal.
Should I try it myself first?
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and does not move well, and getting the depth right matters as much as the look.
What a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions, and the work is guaranteed for a year.
Why act early in Swanwick
Done well, a resealed joint is a neat, straight line that suits the wall. A hurried job with smeared edges and no backing looks worse and fails sooner, so it pays to do it properly once. Where a wall is exposed, as many are in small places like Swanwick, wind-driven rain gets into any failed joint, and damp in older walls is slow to dry out.
Combining jobs into one visit usually makes better use of the time than several visits. We’ll send you a clear quote for the lot.
Why choose Mr Mastic in Swanwick
- Colour agreed with you before we start
- Every job guaranteed for a year
- Anti-fungal silicone where joints get wet
- We leave the area clean and tidy
Take a look at what affects the cost or our reviews.
Questions from Swanwick
Can you help a landlord with a rental near Bursledon station?
Yes, rental work is part of what we do. You can ring 0345 464 0079 or email us with the address and a few details, and we will give you a fixed price before any work starts.
Does the coastal weather in Swanwick affect outside sealant?
Coastal weather is harder on outside sealant: there’s more wind-driven rain and, closer to the shore, salt in the air. Choosing the right sealant for the frame and wall, laid at the right depth, helps it last.
Can new sealant go over the old?
No, and we never do. It can look neat for a few weeks, but the new layer lifts away from the old one. The old sealant has to come out completely.
Are you an approved applicator?
Yes. We are an ARBOMaster approved applicator.
Should I try DIY first?
It depends on the job. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional, while a short indoor joint may be within reach.
Why do you put foam in the joint first?
The foam is closed-cell backing rod. It stops the sealant going in too deep and bonding to three sides, which would stop it stretching.
Is it messy?
We keep the work tidy. Nearby surfaces are protected, and the area is left clean when we finish.
Can a movement joint be filled with mortar?
No. Rigid materials cannot move with the wall and the joint fails. Where a joint has been mortared, it can often be raked out and sealed properly.
Common problems we fix in Swanwick
Weeds, moss and debris in a joint are a sign the sealant has gone. Dirt and roots then trap moisture in the joint and speed up the damage.
It’s worth asking for a quote if you see:
- Moss and dirt in joints with no sealant left
- Leaking joints around cladding and façade panels
- Brick movement joints where the sealant has split
- Weathered mastic that no longer stretches
If you live in an older home near Church of St Paul, an extension built onto an older house moves differently, and the joint between them takes the strain.
What your quote should include
- How the colour is chosen
- What the quote includes, VAT included or not
- When the joint can take water or movement
- Are they insured?