Hampshire · England
External Mastic in Northney
External mastic for Northney and the surrounding area: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Panel joints letting water in
- Moss and dirt in joints with no sealant left
- Failed seals between different materials
DIY sealant or a professional job?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and does not move well, and the joint depth matters as much as the finish.
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
External mastic in Northney, done properly
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, leaving it bonded to two faces so it can move with the wall. If you have plants rooting in failed movement joints and joints with sealant missing in places, we can put it right, whatever the surface.
Outside joints can only be sealed when they’re dry, so work in Northney is booked around the forecast. Let us know about access to every wall, plus any garages or outbuildings.
You get a one-year guarantee, the same in Northney as everywhere else we work.
- Where
- Northney (PO11)
- Wider area
- Hampshire
- Guarantee
- A year, on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Updated
- 26 October 2026
What sealant work can’t fix
We won’t take on work that won’t last, so here’s what sealant can’t put right:
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
- Cracks in the bricks or render themselves, away from the joints
- Walls that need new movement joints cut into them
Not sure which it is? You can call 0345 464 0079 or drop us an email and we’ll tell you honestly before you book.
Joints and surfaces we work on
- Concrete & block
- Façade panels
- Joints between brick and frames
- Render & cladding joints
- Brickwork movement joints
- Copings & trims
What external mastic looks like in Northney
Northney is close to 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. Historic houses like Warblington Castle (about 1.1 miles north) are a reminder that the area around Northney 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.
Homes close to Church of St Peter include some older properties, and the joints between older walls, newer extensions and the roofline need a sealant that can move. Rented homes near Warblington station change hands often, and split movement joints are easy to miss on a rental until damp shows inside. Managing a site like Warblington School? Then movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
Northney is about 3 miles south-east of Havant, in Hampshire. Northney gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a one-year guarantee. Northney is one of 683 towns and villages in Hampshire we cover for external mastic.
Every address in PO11 is covered for external mastic. You will find streets such as Northney Lane, Spinnaker Grange and Northney Road, and we cover them all. Close by, we work in North Hayling (1 mile south), Warblington (1 mile north), Tye (1 mile south), Stoke (1 mile south-west) and Langstone (1 mile north-west). We also work in nearby towns such as Gosport (8 miles west), Havant (3 miles north-west), Fareham (10 miles west), Horndean (6 miles north), Waterlooville (5 miles north-west) and Petersfield (12 miles north).
Local landmarks in Northney
Around Northney, our work takes us to homes and buildings near Eames Farm and The Ship Inn, among other places. The closest station to Northney is Warblington station, about 1.7 miles north of the centre. Other landmarks nearby include Havant Museum (1.7 miles north-west) and Havant War Memorial Hospital (2.1 miles north-west). For a walk, there’s Hayling Billy.
Northney: your questions answered
Is external mastic in a coastal place like Northney any different?
Coastal homes put outside sealant through more weather than inland ones, so the choice of sealant and the preparation matter even more. It’s worth checking the walls that face the sea first.
Do you cover smaller places like Northney?
Yes, we do. Our work covers London and the South East, from towns to the smallest places. The journey is planned ahead, so it helps to know about access.
Can you reach joints on upper floors?
It depends on the building. Tell us the height, the number of joints and what’s below them, and we will confirm what access is needed.
When is the sealant fully cured?
That depends on the sealant used, so please follow the time we give you when we finish.
Will you leave a mess?
No. We work neatly, protect the area around the joints and tidy up afterwards.
What does external mastic cost?
The cost depends on the size of the job, access and how much old sealant has to come out. Call for a quick quote and we’ll talk you through it.
Can I add another job to the visit?
Of course. Combining jobs makes good use of the visit.
Are you fully insured?
Yes. Mr Mastic is fully insured.
Work for landlords, hotels and businesses
From a single let to a portfolio, the work is the same standard: old sealant fully removed, joints prepared properly and a 12-month guarantee.
For anyone letting property in or around Northney, several properties can be quoted together. Send us the addresses and the work at each, and photos by email help.
What affects the quote in Northney
For a quick quote, just ask. The main things that affect it are:
- How many areas need sealing
- Any mould that needs treating
- The type of sealant required
- How much old sealant there is and how hard it is to remove
A failed joint rarely gets cheaper to fix by waiting, because water and mould keep working on it. If you’re unsure, phone 0345 464 0079 or email us for an honest opinion and a quote.
What to tell us for a quote
Photos by email are helpful but not essential. Try to tell us:
- The type of property
- How many joints, rooms or windows are involved
- If someone has resealed it before
- Where the property is
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints, and add photos by email if you can.
Towns and villages near Northney
Other services in Northney
Why act early in Northney
A low-modulus sealant is chosen because it moves without pulling hard at the edges. That matters on brick, render and concrete, which can be weaker at the face. Too stiff a sealant can pull at the edges and break them. Where a wall is exposed, as many are in small places like Northney, wind-driven rain gets into any failed joint, and damp in older walls is slow to dry out.
What it costs depends on how much there is to do, how hard the old material is to remove and how easy the joints are to reach. We give a clear quote before any work starts, so you know where you stand.
Why us?
- A choice of colours where the product allows
- Over 20 years’ experience
- Quality sealants from Arbo and Everbuild
- Domestic, commercial and hotel work
Take a look at what affects the cost or what customers say.
The process
When we arrive, we start by going over the job with you, so you know exactly what we are doing. Surfaces next to the work are protected before work begins. Most jobs take anything from a few hours to several days, depending on the building. Somewhere as small as Northney, access is often the only tricky part. 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.
- Every bit of old sealant and any mortar or debris is cut out.
- The faces are brushed clean and primed where the product requires 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
- Let us know if you’ve seen damp or leaks
- Let us know about stairs, lifts or work at height
- Keep children and pets away from the work area
Get a quote
Want a quote for external mastic? Please phone 0345 464 0079 or drop us an email and tell us about the job. You will know what we plan to do, and what it will cost, before any work begins.
Related advice
How to look after the new joints
Once the sealant has cured, a few habits help it last:
- Show decorators and builders where the movement joints are
- Keep water from gutters off the wall
- Act on the first splits you see
- Keep soil, plants and ivy away from the joints
If you have more work done on the wall, such as new render, cladding or an opening, show the contractor the movement joints. They must stay as flexible joints, never rendered or pointed over.
Once a joint can’t move, the wall finds another way, normally as cracking in the brickwork or render nearby. Catch it early and you reduce the risk.