Southampton · England
External & façade joints in Rownhams, Southampton
Problem with your movement joints in Rownhams? We remove the old material, prepare the joints and seal them properly, with a 12-month guarantee.
- Failed seals between different materials
- Sealant pulling away from one side of the joint
- Failed sealant between panels on a façade
About our external mastic in Rownhams
As ARBOMaster approved applicators, we choose exterior sealants to suit the joint and the surfaces. Some surfaces need a primer before sealing, and we don’t skip that step. If you’re dealing with weeds or debris growing in open joints and joints pointed up with cement by mistake, we can help, whatever the surface.
In a smaller place like Rownhams, some homes face open ground, and walls and rooflines facing the weather take the worst of it. That’s where gutter joints and wall joints tend to fail first.
Whatever the size of the job, it’s backed by our one-year guarantee in Rownhams and across Southampton.
- Where
- Rownhams (SO16)
- Region
- Southampton
- Guarantee
- One year on every job
- Price
- A clear price before we start
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Walls and rooflines in Rownhams
Rownhams 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. The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
For an older house near a landmark such as Church of St John, an extension built onto an older house moves differently, and the joint between them takes the strain. Rented homes near Redbridge station change hands often, and failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Rownhams is about 3 miles north-east of Totton, in Southampton. We provide external mastic to householders, landlords and businesses in Rownhams and the surrounding area. We cover 40 towns and villages across Southampton, from the larger towns to small villages.
All of SO16 is within our area for external mastic, from the main roads to the quietest streets. You’ll find streets such as Rownhams Way, Horns Drove and Rownhams Close. We also cover the places around Rownhams: Upton (1 mile west), Nursling (1 mile south-west), Hillyfields (1 mile south-west), Lordswood (1 mile south-east) and Toothill (1 mile north-west). We also work in nearby towns such as Southampton (3 miles south-east), Townhill Park (4 miles east), Midanbury (4 miles east), Thornhill (6 miles south-east), Chartwell Green (5 miles east) and Harefield (5 miles south-east).
What’s near Rownhams
Around Rownhams, our work takes us to homes and buildings near Oaklands Community School, St James' Park and Oasis Academy Lord's Hill. The closest station to Rownhams is Redbridge station, about 2.1 miles south. Nearby you will also find Princess Anne Hospital (1.3 miles south-east) and Eling Experience (2.4 miles south-west). Open spaces near Rownhams include Testwood Lakes.
What sealant work can’t fix
To be straight with you, some problems need a different trade:
- Cracking across the wall rather than at a joint
- Adding movement joints to masonry that has none
- Damp that is not coming from the joint
If in doubt, call 0345 464 0079 or email us and we’ll say what we think.
Joints and surfaces we work on
- Copings & trims
- Brickwork movement joints
- Façade panels
- Joints between brick and frames
- Render & cladding joints
- Concrete & block
How the job changes by surface
Brickwork movement joints
Vertical joints in long brick walls let the brickwork expand without cracking. We reseal them with a low-modulus sealant over backing rod coloured to suit the wall.
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.
Common problems we fix in Rownhams
Every building moves. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. The sealant in the movement joints takes that strain.
Common reasons people contact us include:
- Moss and dirt in joints with no sealant left
- Rain getting behind render or cladding at a joint
- Rigid filler in a joint that should flex
- Leaking joints around cladding and façade panels
Schools such as Rownhams St John's Church of England Primary School are buildings too, and movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
What your quote should include
- Whether all the old sealant comes out first
- Whether VAT is included
- What product goes in the joint
- What happens if the job turns out different
Keeping the joints in good condition
Aftercare is simple:
- Get split or bare joints resealed while the damage is small
- Look over the joints every year, ideally after winter
- Never let anyone fill a movement joint with mortar
- Keep water from gutters off the wall
Make sure anyone working on the wall later knows where the movement joints are. They should be kept open and resealed, not filled.
Act while the splits are small. At that stage it’s a simple cut out and reseal before water has had years to get in.
Why deal with it now?
An open joint keeps letting water into the wall with every downpour. Wet masonry is more easily damaged by frost near the open joint, so the problem grows beyond the joint itself. Homes in smaller places like Rownhams can face more weather, and failed outside joints let damp into walls. Inside, a split seal lets water into floors and panels just as it would anywhere.
A few things move the cost up or down: the old material and how easily it comes out, whether mould needs treating, and whether the work is at height. We take all of that into account in your quote.
Why choose Mr Mastic in Rownhams
- 4.9 on Google from 180+ five-star reviews
- Colour picked to suit the job
- More than 20 years in sealant work
- We leave the area clean and tidy
More services for Rownhams
Questions from Rownhams
Is external mastic in a coastal place like Rownhams any different?
Near the sea, outside joints face more wind, rain and salt than they would inland, so preparation and the right sealant matter all the more. Walls facing the sea are normally the first to need attention.
I let a flat near Redbridge station. Can you help?
Yes, landlords and agents are among the people we work for. You can ring 0345 464 0079 or email us with the details for a clear quote.
Do you have insurance?
Yes. We are fully insured.
Are you an approved applicator?
Yes. ARBOMaster is the approved applicator scheme for Arbo sealants, and we are part of it.
Is there a guarantee?
Yes. All our work carries a one-year guarantee.
How often do external joints need resealing?
That depends on the wall, the weather and the movement. Look for splits, hardening or edges coming away and have them redone then.
How much does external mastic cost in Rownhams?
The cost depends on the size of the job, access and how much old sealant has to come out. Call for a quick quote.
Do you come to Rownhams?
Yes. We cover Rownhams and the rest of Southampton. For a quote, ring 0345 464 0079 or drop us an email.
DIY versus a professional finish
If you’ve already had a go yourself, that is fine. We remove it and do the joint properly, so tell us about it when you ask for a quote.
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
What happens on the day
On the day, there’s very little for you to do. Show us the job and we will take it from there. The work itself takes anything from a few hours to several days, depending on the building from start to finish. In a smaller place like Rownhams, 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.
- We cut out the failed sealant and rake out any dirt or growth.
- We clean both faces of the joint and prime them where the product calls for it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Before we arrive
- Let us know about parking restrictions
- Where the joints are inside, avoid wetting them before we arrive
- Mention any leaks or damp you’ve noticed
Get a quote
Call for a quick quote, or send an email if you’d rather. Tell us about the joints that need doing and we will explain what’s involved.