Southampton · England
Sand Mastic in Swaythling
Sand mastic in Swaythling from a team with over 20 years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Weathered mastic on the most exposed windows
- Window mastic to renew ahead of painting
- A silicone bead on a sash window that spoils the look
Signs you need sand mastic in Swaythling
Previous repairs in cement or silicone often trap water or crack away. They don’t suit the joint and we normally remove them.
The problems people normally mention when they call include:
- Failed mastic on an exposed elevation
- Window mastic to renew ahead of painting
- Cracked mastic round a front door frame
- Gaps between timber frames and stone or brick
For landlords with property near Swaythling station, cracked sand mastic around sash windows lets in the draughts tenants complain about.
Before you book anyone
- How hidden problems are handled
- Which sealant they’ll use, and why
- Is VAT in the price?
- What insurance they hold
Sand mastic for homes and businesses in Swaythling
Sand mastic doesn’t last for ever, leaving gaps round the window. Renewing it closes the gap and tidies the surround. We work on sash and case windows, tenement windows and stone surrounds, and common reasons people get in touch are modern sealant on a period surround and mastic that needs renewing before redecorating.
Homes around Swaythling range from older properties to newer houses, and their windows range just as widely. The right sealant depends on the frame and on what it sits in.
There’s a 12-month guarantee on every job, whatever its size.
- Place
- Swaythling (SO16, SO18, SO17)
- Region
- Southampton
- Cover
- 12 months on all our work
- Price
- A clear price before work begins
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
For landlords and businesses
Whether it’s one flat or a portfolio, the work is the same standard: old sealant fully removed, joints prepared properly and a 12-month guarantee.
Housing providers, facilities teams and property managers book us too in Swaythling and across Southampton. We can quote a run of properties together, and we are fully insured.
How we quote for sand mastic
You will get a clear quote before work begins. It takes into account:
- The old material and how stubborn it is
- How many rooms, windows or areas are involved
- Which sealant suits the joint
- When we can work, for business premises
The cost depends on the amount of work, how much old material has to come out and how easy the joints are to reach. We give a clear quote before we start, so you know where you stand.
Asking for a quote
What to tell us when you ask for a quote:
- The type of property
- The address or postcode of the job
- Roughly how big the job is
- What the problem is, such as mould, gaps, leaks or cracking
We do not publish a price list. Instead, we give you a clear price for your job. To get started, phone 0345 464 0079 or send us an email.
Swaythling questions
Can you help a landlord with a rental near Swaythling station?
Yes, we work for landlords and letting agents. You can call 0345 464 0079 or email us with the address and a few details, and we will give you a fixed price before any work starts.
Can you do sand mastic in Swaythling?
Yes, Swaythling is within the area we cover. We work across London and the South East. You can phone 0345 464 0079 or email us and tell us what needs doing, and we will send you a clear quote.
Do you hold any approvals?
Yes. We’re ARBOMaster approved, the scheme for applicators of Arbo sealants.
Do I need to be at home?
For indoor joints, yes, someone needs to let us in. After that, you can carry on with your day.
What is sand mastic?
It’s the traditional filler for the joint round timber windows and doors. It’s made with sand and a linseed-oil-based binder.
How long does the job take?
Typically it takes anything from a few hours to a full day, depending on how many windows. Bigger jobs take longer, and we will tell you how long to expect.
Should I try DIY first?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. Most DIY failures come from sealing over old material, wet joints or too much sealant.
Which is right for my windows, sand mastic or modern sealant?
For period timber windows in stone or brick, sand mastic is often the better fit. On modern frames, we’d normally use a flexible sealant, and we will explain why.
DIY sealant or a professional job?
If you’ve already had a go yourself, that’s fine. We cut it out and start again, so just mention it when you contact us.
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.
How to look after the new joints
Good habits help new joints last longer. A few tips:
- Avoid patching sand mastic with silicone
- Do not paint over the new mastic
- Sort the mastic before the decorators arrive
- Make sure water runs off the sill
Avoid sealing over the mastic with silicone. If you see a crack, ask us to take a look rather than patching it.
It’s best to renew mastic before painting the windows. Painting over failed mastic hides the problem for a while.
What happens on the day
Our applicators work methodically: protection first, then preparation, sealing and a tidy-up. Typically it takes a few hours for a single window, longer for several and we leave things clean and tidy. A visit to Swaythling is planned like any other: the time, the access and where to park are agreed in advance. Outdoor jobs depend on a dry day, since sealant needs a dry surface.
- Each surround is checked first.
- The joint is raked out and cleaned.
- We fill deep gaps so the new mastic is not too thick.
- New sand mastic is applied and shaped by hand.
- The finish is dressed neatly.
How to prepare
- Let us know about parking restrictions
- Let us know about earlier repairs to the joints
- Where the joints are inside, avoid wetting them before we arrive
Get a quote
To get a quote, call 0345 464 0079 or drop us an email and tell us where the job is and what the problem looks like. You will have a clear quote before work begins.
Advice
Nearby places to Swaythling
More services for Swaythling
Different surfaces, different methods
Timber door frames
Sand mastic is used round timber door frames too. We renew it the same way as on windows.
Tenement and terrace windows
Tenements and terraces often have many sash windows with ageing mastic. We can do one window or several.
Frames and glazing around Swaythling
With historic houses such as South Stoneham House (about 0.3 miles south-east) nearby, there’s older building stock in the area around Swaythling as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window. Rainfall in the South East is lower than in much 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 St. Mary's Church, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. Managing a site like Mansbridge Primary School? Then its window and door frames need their mastic kept sound, just like a home’s.
Swaythling is about 2 miles north of Southampton, in Southampton. For sand mastic in and around Swaythling, please ring 0345 464 0079 or email us for a quick quote. We cover Southampton from our Crawley base. 40 places in Southampton are on our list, large and small.
All of SO16, SO18 and SO17 is within our area for sand mastic, from the main roads to the quietest streets. Local streets include High Road, Wide Lane and Lilac Road, and we cover them all. Neighbouring places we cover for sand mastic include Bassett Green (1 mile west), Mansbridge (1 mile east), North Stoneham (1 mile north), Portswood (1 mile south-west) and St Denys (1 mile south). Larger places within reach include Shirley (3 miles south-west), Regents Park (3 miles south-west), Thornhill (3 miles south-east), Itchen (3 miles south), Sholing (3 miles south) and Maybush (3 miles west).
Landmarks near Swaythling
Typical jobs here are in homes near Saint George Catholic Voluntary Aided College Southampton, Riverside Park and Saint George Catholic Voluntary Aided College Southampton. There’s a railway station in Swaythling itself: Swaythling station. Nearby you will also find Marlands Shopping Centre (2.6 miles south-west) and Bitterne Local History Society Heritage And Research Centre (1.9 miles south). Open spaces near Swaythling include Netley Common.