Hampshire · England
External & façade joints in Cheriton, Hampshire
External mastic in Cheriton from a team with over 20 years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Brick movement joints where the sealant has split
- Gaps where render, brick and frames meet
- Rigid filler in a joint that should flex
DIY sealant or a professional job?
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach 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. Silicone doesn’t stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
External mastic in Cheriton
A movement joint is only as good as its depth. Closed-cell backing rod sets the depth and stops the sealant sticking to the back, leaving it bonded to two faces so it can move with the wall. Typical jobs include rain getting behind render or cladding at a joint and rigid filler in a joint that should flex, on joints between brick and frames, façade panels and copings & trims.
In a village or hamlet like Cheriton, older cottages and farm buildings often stand in the open, where walls and rooflines take the weather head on. Joints on those walls need a sealant that moves with the building and stays in place.
The work is guaranteed for twelve months. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Location
- Cheriton (SO24)
- Region
- Hampshire
- Cover
- 12 months on all our work
- Price
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
The process
Our applicators work methodically: protect, prepare, seal, tidy. Typically it takes anything from a few hours to several days, depending on the building. Somewhere like Cheriton 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 look at every joint and agree a colour to suit the wall.
- Failed sealant is removed back to clean, sound faces.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- Primer is applied wherever the sealant needs it.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
How to prepare
- Mention any tricky access
- Let us know about parking restrictions
- Mention if the joints have been sealed before
How to get a quote
To get a quote, phone 0345 464 0079 or email us and tell us where the job is and what the problem looks like. We will give you a clear quote before any work starts.
Advice
How the job changes by surface
Brickwork movement joints
Clay brickwork grows slightly over its life and moves with the weather. The movement joint takes that up, so its sealant has to stay flexible.
Joints between dissimilar materials
Joints where frames, sills or panels meet the wall are common leak points. We cut out the old sealant and reseal with a product suited to both surfaces.
Cheriton: your questions answered
Can you do external mastic in Cheriton?
Yes. We work across London and the South East, and Cheriton is part of that. Just call 0345 464 0079 or drop us an email with a few details of the job, and we’ll send you a clear quote.
Will you come out to Cheriton?
Yes, we do. We work across London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
Is there a guarantee?
Yes. All our work carries a 12-month guarantee.
Where is Mr Mastic based?
Our base is in Crawley, and we work across South East England, London and Scotland.
Can new sealant go over the old?
No, and we never do. It may look fine at first, but the new layer lifts away from the old one. The old sealant has to come out completely.
Is it OK to fill a movement joint with cement?
No. Cement or mortar cannot stretch and the joint fails. If it has already been filled, we can generally cut it out and reseal it.
Will you leave a mess?
We keep the work tidy. We protect what’s around the joints, and we clear up when we are done.
How long does the job take?
Most jobs take anything from a few hours to several days, depending on the building, including preparation and clearing up. Your quote will say how long we expect yours to take.
Looking after it afterwards
Aftercare is simple:
- Have failed joints looked at early
- Make sure movement joints aren’t pointed over
- Look over the joints every year, ideally after winter
- Ask before painting over external sealant
Do not paint over the new sealant unless we’ve said the product is paintable. Paint can crack on a flexible joint, and paint can crack as the joint moves.
Act while the splits are small. Then it’s a straightforward cut-out and reseal before water has had years to get in.
Quotes for external mastic in Cheriton
Some jobs are bigger than they look, and some smaller. The main factors:
- How many areas need sealing
- Any mould that needs treating
- The amount of work
- How much old sealant there is and how hard it is to remove
Some things make a job bigger or smaller: how much old sealant there is and how stubborn it is, any mould to treat, and whether we need extra access for height. We take all of that into account in your quote.
What to tell us for a quote
Photos by email are helpful but not essential. Please mention:
- Roughly how big the job is
- Where the job is, and your postcode
- Whether it has been sealed before
- If it’s domestic, commercial or a hotel
Want a quote for external mastic? Please ring 0345 464 0079 or email us with a few details. You will know what we plan to do, and what it will cost, before any work begins.
More services for Cheriton
What we’re called out for in Cheriton
Every building moves. Brickwork grows a little over the years, blockwork and concrete shrink, and all of it moves with heat and moisture. All of that ends up in the joint sealant.
Signs it’s time to call us include:
- Sealant pulling away from one side of the joint
- Rain getting behind render or cladding at a joint
- Old sealant gone brittle and cracked
- Cracked joints where brick meets render or frames
Homes close to Church of St Michael include some older properties, and an extension built onto an older house moves differently, and the joint between them takes the strain.
Questions to ask before you book
- How the surfaces are prepared before sealing
- How long to leave it before use
- The length of the guarantee
- Who turns up on the day
Walls and rooflines in Cheriton
Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Historic houses like Hinton Ampner House (about 0.8 miles south-east) are a reminder that the area around Cheriton has older buildings as well as new. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth.
Schools such as Cheriton Primary School are buildings too, and movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
Cheriton is about 7 miles east of Winchester, in Hampshire. Wherever you are in the SO24 postcode area, we can carry out external mastic at your property. Our area takes in 683 places across Hampshire, from the larger towns to small villages. Our Southampton page covers work nearby, about 14 miles away.
Postcode districts we cover here for external mastic: SO24. Streets in the area include Lower Lamborough Lane, Raebarn Close and Markall Close. Nearby, we also carry out external mastic in Hinton Ampner (1 mile east), Beauworth (2 miles south-west), Bramdean (2 miles east), New Alresford (2 miles north) and Bishop's Sutton (3 miles north-east). We also work in nearby towns such as Basingstoke (15 miles north), Winchester (7 miles west), Havant (15 miles south-east), Eastleigh (10 miles south-west), Fareham (14 miles south) and Horndean (12 miles south-east).
Local landmarks in Cheriton
In Cheriton, that means homes and buildings near The Flowerpots Inn. For a walk, there’s Beacon Hill and Shutts Copse.
What sealant work can’t fix
We won’t take on work that will not last, so here’s what sealant cannot put right:
- Subsidence or other structural problems
- Loose or hollow render, which needs re-rendering
- Cracks in the bricks or render themselves, away from the joints
Not sure which it is? You can ring 0345 464 0079 or email us and we’ll tell you honestly before you book.
Surfaces we seal
- Joints between brick and frames
- Concrete & block
- Copings & trims
- Brickwork movement joints
- Render & cladding joints
- Façade panels