Hampshire · England
South Down Sand Mastic
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for householders, landlords and businesses in South Down. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Old cement repairs round a window that have failed
- Mastic that needs renewing before redecorating
- Old sand mastic that has cracked, crumbled or fallen out
How we handle sand mastic in South Down
Sand mastic suits most period window surrounds. Newer frames generally get a flexible sealant instead, and we will talk through which suits your home. We work on sash and case windows, period & listed homes and brick reveals, and the jobs we see most are old cement repairs round a window that have failed and mastic worn away on windows facing the weather.
Around South Down, many homes face open ground, so their windows and doors take the full weather. Exposed frames and sills lose their mastic sooner than sheltered ones.
Each job carries a 12-month guarantee, large or small.
- Where
- South Down (SO21)
- Region
- Hampshire
- Cover
- One year on every job
- Quote
- A clear price before we start
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Quotes for sand mastic in South Down
Your quote is based on your job. We take into account:
- Whether there’s mould to deal with
- How easy the joints are to reach
- The old material and how stubborn it is
- Working hours on commercial sites
The cost reflects the work involved, not a rough estimate. That is why we ask a few questions first and give you a clear quote before we start.
Asking for a quote
When you contact us, these details help:
- Whether it’s a home or a business
- What the problem is, such as mould, gaps, leaks or cracking
- Whether it has been sealed before
- How many joints, rooms or windows are involved
For a quote, ring 0345 464 0079 or drop us an email with the location and a short description of the problem. You will have a clear quote before any work starts.
For landlords and businesses
Hotels need rooms back in use, so the work can be planned room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
Water getting past a failed joint can damage the building, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance that we can handle for you.
What happens if it’s left?
New sash windows are a major, costly change and on a listed home, consent may be needed. If the frames are sound, renewing the mastic deals with gaps and draughts at the surround. Where a wall is exposed, as many are in small places like South Down, wind-driven rain gets into any failed joint, and damp in older walls is slow to dry out.
The cost depends on the size of the job, how hard the old material is to remove and how easy the joints are to reach. We give a clear quote before work begins.
Why book with us
- ARBOMaster approved applicator
- We never seal over old sealant
- Rated 4.9 stars on Google
- Fully insured
Take a look at what affects the cost or our reviews.
Places near South Down
Other services in South Down
DIY sealant or a professional job?
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, and the work is guaranteed for a year.
Different surfaces, different methods
Tenement and terrace windows
In shared buildings, the windows may be part of a wider repair, so check who is responsible first.
Timber door frames
Sand mastic is used round timber door frames too. The method is the same as for windows.
The process
Before we leave, we go over the finished joints with you. The work normally takes anything from a few hours to a full day, depending on how many windows, depending on the size of the job. Somewhere like South Down needs a little journey planning: tell us about narrow lanes, gates, long drives and where we can park. Everything for the job comes with us, so a second trip is avoided where possible.
- We check each window surround and the condition of the joint.
- The joint is raked out and cleaned.
- Large voids are packed out.
- New sand mastic is applied and shaped by hand.
- We finish the mastic to a tidy line.
How to prepare
- Let us know about parking restrictions
- Clear items away from the joints we’re working on
- For business premises, tell us about site rules or sign-in
How to get a quote
A good description makes for an accurate quote. Tell us where the job is, what’s wrong and how much there is, and add photos by email if you can.
Read more
Sand mastic in South Down: local notes
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 All Saints, the joint between an old wall and a newer frame is usually the first place rain gets in. Managing a site like Twyford St Mary's Church of England Primary School? Then larger buildings have plenty of frames, and the mastic around each one ages.
South Down is about 3 miles north-east of Chandler's Ford, in Hampshire. Jobs in South Down get the same care as everywhere else we work: old sealant removed completely, careful preparation and a one-year guarantee. Our Hampshire coverage runs to 683 places, South Down among them. Our Southampton page covers work nearby (7 miles or so).
Our applicators cover all of SO21 for sand mastic and the streets around it. Streets in the area include Cross Way, Fairfield Road and Grove Road, and we cover them all. Close by, we work in Compton (1 mile north), Otterbourne (1 mile south-west), Shawford (1 mile north-east), Twyford (1 mile east) and Oliver's Battery (2 miles north). Larger places within reach include Winchester (3 miles north), Eastleigh (3 miles south), Fareham (13 miles south-east), Andover (15 miles north-west), Totton (10 miles south-west) and Chandler's Ford (3 miles south-west).
What’s near South Down
In South Down, that means homes and buildings near The Bridge Inn and Thornden School, among other places. For rail, the closest station is Shawford station, roughly 0.6 miles north-east of the centre. A little further out are Balfour Museum of Hampshire Red Cross History (2.9 miles north) and Wolvesey Castle (3.2 miles north). Green spaces nearby include Twyford Down and Shawford Down.
Your questions about sand mastic in South Down
Can you do sand mastic in South Down?
Yes, South Down is within the area we cover. We work across London and the South East. You can call 0345 464 0079 or email us and tell us what needs doing.
Do you cover smaller places like South Down?
Yes, we do. We work across London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
What exactly is sand mastic?
A traditional pointing material made from sand and a linseed-oil-based binder, used between timber frames and stone or brick.
What sealant do you use?
Products from Arbo and Everbuild, among others, picked for each joint. We’ll tell you what we are using and why.
Can I paint the new mastic?
The usual advice is to leave sand mastic unpainted. Ask us before you decorate around it and we will talk you through it.
Can new sealant go over the old?
No. Fresh sealant doesn’t stick to old sealant, and it traps any mould or water underneath. We remove it all first.
Where is Mr Mastic based?
Our base is Crawley. Our area covers South East England, London and Scotland.
Do you do commercial work?
Yes. We’ve worked for hotels, offices and other businesses, and we are fully insured.
Common problems we fix in South Down
Timber frames move with the seasons. The movement cracks the mastic little by little.
Common reasons people contact us are:
- Open joints round the window box
- Old cement repairs round a window that have failed
- Crumbling sand mastic round a window
- Window mastic to renew ahead of painting
Rented homes near Shawford station change hands often, and cracked sand mastic around sash windows lets in the draughts tenants complain about.
What your quote should include
- Whether they’re fully insured
- What the cure time is
- How much experience the applicator has
- Is VAT in the price?