Hampshire · England
External Mastic in Stonymarsh
Professional external mastic in and around Stonymarsh, with every bit of old sealant taken out first.
- Weathered mastic that no longer stretches
- Water getting into walls through failed joints
- Movement joints filled with mortar instead of sealant
Stonymarsh: your questions answered
Is Stonymarsh within the area you cover?
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.
Do you cover Stonymarsh for external mastic?
Yes. We work across London and the South East, and Stonymarsh is part of that. Just call 0345 464 0079 or drop us an email with a few details of the job.
Can I add another job to the visit?
Yes. Just list everything you need.
What information do you need?
Where the job is, what the problem is and roughly how big it is. If you can, email a few photos.
Should I try DIY first?
That depends on the joint. 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.
Can you seal joints between two different materials?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. The colour is chosen to suit.
Can you reach joints on upper floors?
It depends on the building. Send us pictures and a rough idea of the height, and we’ll confirm what access is needed.
Do you work for hotels and businesses?
Yes. Larger jobs can be planned room by room or area by area to suit the site.
About our external mastic in Stonymarsh
Ground-floor and low-level joints are straightforward to reach. For joints higher up, give us some details of the building and we’ll confirm what access is needed. We are often asked to deal with movement joints filled with mortar instead of sealant and water getting into walls through failed joints, across render & cladding joints, concrete & block and joints between brick and frames.
Older homes in small places like Stonymarsh may be stone, brick or timber-framed, often with later extensions. Where one material meets another is where water generally gets in.
Your job is guaranteed for a year, as with all our work.
- Location
- Stonymarsh (SO51)
- Region
- Hampshire
- Cover
- 12 months on all our work
- Price
- A clear price before we start
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Aftercare tips
Joint life depends on how it’s used and looked after. We suggest:
- Leave the joints unpainted unless we’ve said otherwise
- Fix overflowing gutters above sealed joints
- Act on the first splits you see
- Keep soil, plants and ivy away from the joints
Keep the joints clear of soil, plants and climbing growth. Damp material against the sealant shortens its life.
Small splits are the time to act. At that stage it’s a simple cut out and reseal before water has had years to get in.
What we are called out for in Stonymarsh
Buildings move more than people expect. Brickwork grows a little over the years, blockwork and concrete shrink, and all of it moves with heat and moisture. The sealant in the movement joints takes that strain.
Common reasons people contact us are:
- Panel joints letting water in
- Sealant that has lost its bond to the brick or render
- Hard, crazed mastic that has stopped moving
- Movement joints with cracked, split or missing sealant
Rented homes near Mottisfont & Dunbridge station change hands often, and failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Comparing quotes
- When the joint can take water or movement
- Who turns up on the day
- Is VAT in the price?
- How hidden problems are handled
What we do, step by step
We work through the job in order: protection first, then preparation, sealing and a tidy-up. For most jobs that takes a few hours to a few days, depending on the length of joint and the access. Somewhere as small as Stonymarsh, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- We look at every joint and agree a colour to suit the wall.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- We prime the faces where required.
- We gun in low-modulus sealant and tool it neatly.
How to prepare
- Tell us if parking is tricky
- Keep pets and children clear of the area while we work
- Move anything stored near the joints
Get a quote
Want a quote for external mastic? Please call 0345 464 0079 or send us an email with a few details. You will know what we plan to do, and what it will cost, before any work begins.
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Towns and villages near Stonymarsh
Other services in Stonymarsh
What external mastic looks like in Stonymarsh
With historic houses such as Mottisfont Abbey (about 0.5 miles west) nearby, there’s older building stock in the area around Stonymarsh as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. 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.
In the older streets around Church of St Andrew, older walls, gutters and the joints where extensions meet them need a flexible sealant.
Stonymarsh is about 4 miles north-west of Romsey, in Hampshire. From the centre of Stonymarsh to the outskirts, we cover external mastic for every kind of property. Stonymarsh is one of 683 towns and villages in Hampshire where we work. You can also see our page for Southampton, roughly 10 miles from Stonymarsh.
Here we cover the SO51 postcode area for external mastic. Close by, we work in Mottisfont (1 mile west), Michelmersh (1 mile south-east), Kimbridge (1 mile south-west), Dunbridge (1 mile south-west) and Timsbury (1 mile south-east). Larger places within reach include Winchester (9 miles east), Eastleigh (9 miles south-east), Andover (12 miles north), Totton (8 miles south), Chandler's Ford (7 miles south-east) and Hedge End (13 miles south-east).
Landmarks near Stonymarsh
Locally, jobs take us to homes and businesses close to The Bear And Ragged Staff Public House. The nearest railway station is Mottisfont & Dunbridge station, roughly 1.1 miles west of the centre. A little further out are Romsey Community Hospital (3.7 miles south-east) and King Johns House (3.5 miles south). Not far away are Emer Bog and Baddesley Common.
Quotes for external mastic in Stonymarsh
The quote reflects the job in front of us. We take into account:
- How many areas need sealing
- The amount of work
- The product the joint needs
- Whether the work is at height
Instead of a standard rate, we price the job in front of us: the amount of work, the old material and the access. The price is agreed before we begin.
What to tell us for a quote
A few details help us give you an accurate quote. When you get in contact, it helps to mention:
- Pictures of the joints, sent by email
- The rough size of the job
- What’s wrong with the joints now
- Whether it has been sealed before
To get a quote, ring 0345 464 0079 or send us an email and tell us where the job is and what the problem looks like. We will send you a clear quote before any work starts.
How the job changes by surface
Cladding and façade panels
Panels heat up and cool down quickly, so the joint sealant has to cope with frequent movement. We choose the product to suit.
Copings and trims
Coping and trim joints face rain and sun head on. Each is resealed with a weatherproof, flexible sealant.
Should I try it myself first?
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and getting the depth right matters as much as the look.
Sealing over old silicone is the commonest DIY error. New silicone won’t bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
What we cannot put right
Some problems need a builder, plumber or other trade rather than us:
- Failed render or damaged cladding panels
- Cracked brickwork or render that needs a builder or plasterer
- Subsidence or other structural problems
If you are not sure, just call 0345 464 0079 or send us an email and we will give you a straight answer before you book.
Surfaces we seal
- Brickwork movement joints
- Copings & trims
- Façade panels
- Render & cladding joints
- Concrete & block
- Joints between brick and frames