Greater London · England
Seething Wells Sand Mastic
Traditional burnt sand mastic around sash and case windows and doors in stone and brick in Seething Wells, with a one-year guarantee on every job. Call for a quick quote.
- Tired mastic found when preparing windows for paint
- Gaps between timber frames and stone or brick
- Mastic worn away on windows facing the weather
Aftercare tips
So the new joints stay in good condition:
- Leave the new mastic unpainted
- Go gently near the mastic when preparing windows
- Find out about consent before window work on a listed home
- Keep modern sealant off the mastic
Check the mastic when you check the paintwork. Catching cracks early keeps repairs small.
Renewing mastic before redecorating saves doing it twice. Paint over cracked mastic only covers it up.
About our sand mastic in Seething Wells
Sand mastic suits most period window surrounds. On modern frames we’d normally use a flexible sealant, and we’ll talk through which suits your home. If you are dealing with cement or filler used on old window joints that has cracked and crumbling sand mastic round a window, we can help.
Much of London’s older housing was built with timber sash windows, some still in place and some long since replaced. Whatever is in the opening now, the joint between frame and wall is what keeps the weather out, in Seething Wells as anywhere.
The work is covered for a year after we finish. If anything isn’t right with it, phone 0345 464 0079 or email us.
- Place
- Seething Wells (KT6, KT1, KT7)
- Region
- Greater London
- Guarantee
- 12 months on all our work
- Quote
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Should I try it myself first?
Sealing over old silicone is the commonest DIY error. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
How we quote for sand mastic
Jobs vary more than people expect. What affects the quote:
- How much there is to do
- Mould in or behind the old joints
- Whether old sealant or filler has to be cut out
- The type of sealant required
Commercial jobs are quoted on the same basis as homes: the amount of work, the access and the products needed, plus any working-time requirements on site. Ask us for a quote and we’ll go through it with you.
What we need to know
When you call or email, these details help:
- Pictures of the joints, sent by email
- Access, such as stairs, a lift or height
- The type of property
- If someone has resealed it before
Asking for a quote is easy: let us know the job and the location and its rough size. A few photos by email make the job easier to understand.
Honest limits
A few problems are outside what sealant work can do:
- Decayed frames that need repair
- Broken panes
- Masonry that needs repairing
Not sure which it is? You can phone 0345 464 0079 or drop us an email and we’ll tell you honestly.
Where we work in Seething Wells
- Stone surrounds
- Timber door frames
- Brick reveals
- Sash and case windows
- Period & listed homes
- Tenement windows
What we’re called out for in Seething Wells
Rain on the window surround works into any crack and pushes it out. Windows facing the weather tend to go first.
Common reasons people contact us include:
- Weathered mastic on the most exposed windows
- Open joints round the window box
- Mastic that needs renewing before redecorating
- Cement or filler used on old window joints that has cracked
Managing a site like Maple Infants' School? Then its window and door frames need their mastic kept sound, just like a home’s.
Questions to ask before booking
- How the surfaces are prepared before sealing
- Who turns up on the day
- How long to leave it before use
- Whether the sealant suits the joint
Towns and villages near Seething Wells
Other services in Seething Wells
Seething Wells: your questions answered
Is parking a problem for a job in Seething Wells?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. That way the visit can be planned around it.
Can you do sand mastic in Seething Wells?
Yes. We work across London and the South East, and Seething Wells is part of that. You can phone 0345 464 0079 or send us an email and tell us what needs doing, and we will give you a clear price.
Will the old sealant be removed?
Yes. All of the old material is cut out and the joint cleaned before applying anything new.
How long does sand mastic take to go off?
It skins over fairly quickly but takes longer to harden fully. We will explain what to expect before we leave.
Where are you based?
Our base is Crawley. We work across South East England, London and Scotland.
How long does the job take?
That depends on the amount of work, but as a guide it takes a few hours for a single window, longer for several. We will tell you when we quote.
What is sand mastic?
Sand mastic is a traditional material for pointing round windows and doors. It’s made with sand and a linseed-oil-based binder.
What does sand mastic cost?
It depends on the job, so we quote each one individually. To get one, call 0345 464 0079 or send us an email and let us know what needs doing and where.
How the visit works
All our tools and materials come with us in the van. Once we’ve agreed what’s being done, the area is protected and the work begins. It normally takes a few hours per window, depending on the condition of the joints. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Seething Wells. It helps if you can point us to a visitor permit or a bay close to the door.
- We check each window surround and the condition of the joint.
- The joint is raked out and cleaned.
- Large voids are packed out.
- We point the joint with sand mastic by hand.
- We finish the mastic to a tidy line.
How to prepare
- Keep pets and children clear of the area while we work
- Tell us about any water getting in
- Mention any parking rules near the property
Get a quote
It all starts with a short chat. Describe the problem, the location and the size of the job, and we will talk you through what we’d do. Whenever you are ready, ring 0345 464 0079 or send us an email.
Related advice
Seething Wells homes and the weather
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 London conversions and blocks, the lease decides who is responsible for the frames, so check that before booking.
In the older streets around St Andrew's Church, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. If you let a flat or house near Surbiton station, cracked sand mastic around sash windows lets in the draughts tenants complain about.
Seething Wells is about 4 miles north-west of Ewell, in Greater London. Across the KT6 area, our applicators can take on sand mastic. Our Greater London coverage runs to 764 places, and Seething Wells is one of them. We also work in London, about 12 miles from Seething Wells.
Here we cover the KT6, KT1 and KT7 postcode area for sand mastic. Streets in the area include Maple Road, Grove Road and North Road, all of which we cover. We also cover the places around Seething Wells: Surbiton Park (1 mile north-east), Long Ditton (1 mile south), Thames Ditton (1 mile west), Ditton Hill (1 mile south) and Weston Green (1 mile west). Within a short drive, we also cover London (12 miles north-east), City of Westminster (11 miles north-east), Marylebone (11 miles north-east), Kensington (9 miles north-east), St Pancras (12 miles north-east) and Shoreditch (14 miles north-east).
Around Seething Wells
In Seething Wells, that means homes and buildings near The Hollyfield School and Sixth Form Centre, The City Arms and Hampton Court Park, among other places. There’s a railway station in Seething Wells itself: Surbiton station. Other landmarks nearby include Chessington Castle Hill (2.6 miles south) and Metropolitan Police Mounted Branch Museum (1.6 miles west). For a walk, there’s The Wood and Kingston Hill Road area.
How the job changes by surface
Sash and case windows
Most of our sand mastic work is on sash windows. Each joint round the box is raked out and renewed.
Timber door frames
Period doors in stone or brick openings are often pointed with sand mastic. The method is the same as for windows.