Portsmouth · England
External Mastic in Landport
External mastic in Landport from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Failed sealant between panels on a façade
- Weathered mastic that no longer stretches
- Failed seals between different materials
For landlords and businesses
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.
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements.
External mastic in Landport
A movement joint is only as good as its depth. Backing rod controls how deep the sealant goes and keeps it off the back of the joint, leaving it bonded to two faces so it can move with the wall. If you’re dealing with movement joints with cracked, split or missing sealant and failed seals between different materials, we can help.
Around Landport, garages, outbuildings and extensions all add to the joints on the outside of a home. Leaks generally start at a gutter end, a garage door frame or where an extension meets the house.
A one-year guarantee comes as standard.
- Where
- Landport (PO1, PO2, PO5)
- Wider area
- Portsmouth
- Guarantee
- A year, on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Updated
- 26 October 2026
What we can’t put right
We won’t take on work that won’t last, so here’s what sealant can’t put right:
- Render that is blown, hollow or coming away
- Structural movement, which needs a surveyor or engineer
- Cracks in the bricks or render themselves, away from the joints
If you’re not sure, just call 0345 464 0079 or email us and we will give you a straight answer.
Joints and surfaces we work on
- Concrete & block
- Façade panels
- Copings & trims
- Brickwork movement joints
- Joints between brick and frames
- Render & cladding joints
Common problems we fix in Landport
Poor preparation causes many early failures: joint faces that were dusty or damp, unprimed where they needed it, or still carrying old sealant. The new sealant then lets go long before it should.
People normally contact us after spotting one of these:
- Old sealant gone brittle and cracked
- Joints with sealant missing in places
- Plants rooting in failed movement joints
- Movement joints filled with mortar instead of sealant
In the older streets around Church of All Saints, older walls, gutters and the joints where extensions meet them need a flexible sealant.
Questions to ask before you book
- Which colour the sealant will be
- Whether all the old sealant comes out first
- When the joint can take water or movement
- Who does the work, and how experienced they are
External mastic in Landport: local notes
Landport is within about 1 mile of the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. That’s hard on movement joints and outside wall joints, especially on the side facing the sea. London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
For site and facilities teams at buildings such as Ark Dickens Primary Academy, 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 Portsmouth & Southsea station, failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Landport is about 1 mile south-west of Portsmouth, in Portsmouth. Whether you are in the middle of Landport or further out, external mastic is available for homes and businesses alike. Our Portsmouth coverage runs to 19 places, and Landport is one of them.
Postcode districts we cover here for external mastic: PO1, PO2 and PO5. You’ll find streets such as Lake Road, Watts Road and Alfred Road, all of which we cover. Nearby, we also carry out external mastic in Portsmouth (1 mile north-east), Fratton (1 mile east), Rudmore (1 mile north), Kingston (1 mile east) and North End (1 mile north). Further out, we also cover Wymering (3 miles north), Paulsgrove (3 miles north), Cosham (3 miles north), Drayton (3 miles north-east) and Farlington (4 miles north-east).
Landmarks near Landport
Typical jobs here are in homes near The Painters Arms, St Edmund's Catholic School and Alexandra Park and the streets around them. Landport has its own railway station: Portsmouth & Southsea station. Well-known places in the area include Royal Portsmouth Hospital (within half a mile south-west) and Charles Dickens Birthplace Museum (less than half a mile north). The countryside around Landport includes Milton Locks and Portsdown Hill.
Landport questions
Can you help a landlord with a rental near Portsmouth & Southsea station?
Yes, we work for landlords and letting agents. You can call 0345 464 0079 or drop us an email with the address and a few details, and we’ll give you a fixed price before any work starts.
Does the coastal weather in Landport affect outside sealant?
Coastal homes put outside sealant through more weather than inland ones, so preparation and the right sealant matter all the more. It’s worth checking the walls that face the sea first.
Can you match the colour of my brickwork?
There’s a good range of exterior colours, including greys, browns, whites and stone tones. We pick the one that suits your wall best so the joint does not draw the eye.
Can you seal joints between render and window frames?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. The colour is chosen to suit.
Do you work at height?
Each building is different. Tell us the height, the number of joints and what’s below them and we’ll confirm how they can be reached safely.
How long will you be here?
A typical job takes a few hours for a handful of joints, longer for a whole elevation, including preparation and clearing up. We’ll confirm how long when we quote.
What’s an expansion joint in brickwork?
Walls move with heat, cold and moisture, and planned joints take up that movement. It’s closed with backing rod and a flexible sealant.
Are you an approved applicator?
Yes. We hold ARBOMaster approved applicator status and we are fully insured too.
The process
There isn’t much for you to do on the day. Point us to the joints and we will get on with it. The job generally takes a few hours for a handful of joints, longer for a whole elevation. In a smaller place like Landport, parking is seldom the issue; lanes, gates and long drives are worth mentioning. If the job is outside, tell us about side access and how high the joints are.
- We inspect the joints and agree which need resealing and how they’ll be reached.
- Old sealant and any debris are cut and raked out.
- Both sides are cleaned back to sound material and primed if needed.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- We gun in a flexible exterior sealant in a colour that suits the wall and tool it neatly.
Before we arrive
- Plan for the work area to be out of bounds to pets and children
- Let us know about stairs, lifts or work at height
- Mention any sign-in or site rules at work premises
How to get a quote
We quote each job on its own, so start by telling us what you need. Simply ring 0345 464 0079 or drop us an email and describe the job and send pictures if you have them.
Advice
DIY versus a professional finish
A DIY attempt does not rule out a professional job. We remove it and do the joint properly.
The difference is mostly in the preparation and the product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, then guaranteed for a year.
Why act early in Landport
Pointing a movement joint with mortar might seem a neat fix, but it stops the joint moving. The wall then cracks somewhere else. A flexible sealant over backing rod is what the joint needs. Around Landport, water from a failed joint in an older home can soak into timber and plaster, which is far harder to put right than the sealant itself.
What it costs depends on the size of the job, how much old material has to come out and access to the work. You will have a clear quote before any work starts, so you know where you stand.
Why choose Mr Mastic in Landport
- ARBOMaster approved applicator
- Anti-fungal sanitary silicone in wet areas
- Domestic, commercial and hotel work
- A 12-month guarantee on all work
Also in Landport
Aftercare tips
Simple care keeps the joints in good condition. Our advice:
- Check external joints each spring
- Leave the joints unpainted unless we’ve said otherwise
- Keep movement joints as flexible joints, not mortar
- Keep water from gutters off the wall
Give the sealant the cure time we tell you before anything rubs against it. The surface skins over quickly, but full cure takes longer.
Act while the splits are small. At that stage it’s a simple cut out and reseal with no damage behind it to deal with.