Greater London · England
Sand mastic for sash & case windows in Winchmore Hill, Greater London
Our applicators work in Winchmore Hill on traditional burnt sand mastic around sash and case windows and doors in stone and brick. Old material cut out, joints cleaned and sealed neatly.
- Open joints round the window box
- Wind and rain getting in round a sash window
- Cracked mastic round a front door frame
Sand mastic in Winchmore Hill
Sand mastic does not last for ever, leaving gaps round the window. Renewing it closes the gap and tidies the surround. We work on brick reveals, period & listed homes and tenement windows, and common reasons people get in touch are cement or filler used on old window joints that has cracked and gaps where the frame meets the masonry.
London’s Victorian and Edwardian terraces were built with timber sash windows, and many still have them or their replacements. Either way, the mastic between frame and brickwork is what stops draughts and rain getting in.
We stand behind the work with a 12-month guarantee, so you’re not left on your own once the job is done.
- Where
- Winchmore Hill (N21, N13, N9)
- Wider area
- Greater London
- Cover
- A year, on every job
- Quotes
- A clear price before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Your questions about sand mastic in Winchmore Hill
Can you help a landlord with a rental near Winchmore Hill station?
Yes. We work for landlords and agents as well as householders. Just phone 0345 464 0079 or send us an email with the address and what needs doing, and we’ll give you a clear quote.
Is Winchmore Hill in your area for sand mastic?
Yes. Our work covers London and the South East, and Winchmore Hill is part of that. Just ring 0345 464 0079 or drop us an email with a few details of the job, and we will give you a clear price.
Is it possible to take out silicone and use sand mastic instead?
Generally, yes. Once the silicone is out and the joint prepared we point it with sand mastic.
Where are you based?
We work from Crawley. We cover Winchmore Hill and the rest of Greater London, along with the rest of our area.
Are you insured?
Yes. We’re fully insured.
How long does sand mastic take to go off?
It takes a while. The skin forms first, and the full set comes later, and we’ll tell you what to expect.
How long does the job take?
Typically it takes a few hours for a single window, longer for several. Larger jobs naturally take longer.
Do you remove the old sealant?
Yes. All of the old material is cut out and the joint cleaned.
DIY versus a professional finish
The biggest DIY mistake is sealing over old sealant. New silicone won’t bond to old, so it lifts and traps water and mould underneath. All the old material has to come out first.
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
When to call us in Winchmore Hill
Previous repairs in cement or silicone often trap water or crack away. They do not suit the joint and we normally remove them.
The most common problems we see are:
- Mastic worn away on windows facing the weather
- Mastic dropping out of the joint
- Wind and rain getting in round a sash window
- Mastic round period door frames that has failed
Letting a property close to Winchmore Hill station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about.
Comparing quotes
- What guarantee comes with the work
- What the cure time is
- Whether the sealant suits the joint
- Whether they seal over old material or remove it
Leave it or put it right?
Not every filler suits an old window surround. Sand mastic matches what was there and that can be important for listed homes. Damp from a failed joint spreads quietly in older London brickwork and timber, and by the time it shows on a wall or ceiling in Winchmore Hill, the repair is bigger than the sealant job would have been.
Homes and businesses are quoted the same way: how much there is to do, how we reach it and what it needs. Call for a quick quote and we will explain what it covers.
Why book with us
- A 12-month guarantee on all work
- Fully insured
- We never seal over old sealant
- More than 20 years in sealant work
Winchmore Hill homes and the weather
Historic houses like Bruce Castle (about 2.6 miles south-east) are a reminder that the area around Winchmore Hill has older buildings as well as new. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window. In London conversions and blocks, the lease decides who is responsible for the frames, so check that before booking.
Winchmore Hill is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. For site and facilities teams at buildings such as St. Paul's School, its window and door frames need their mastic kept sound, just like a home’s.
Winchmore Hill is about 2 miles north-west of Edmonton, in Greater London. Whether you’re in the middle of Winchmore Hill or further out, we cover sand mastic for every kind of property. Our area takes in 764 places across Greater London. You can also see our page for London, roughly 9 miles from Winchmore Hill.
We work across N21, N13 and N9 for sand mastic and the streets around it. Streets in the area include Farm Road, Arlow Road and Hurst Road. Nearby, we also carry out sand mastic in Bush Hill (1 mile north-east), Bush Hill Park (1 mile north-east), Enfield (1 mile north-east), Enfield Chase (2 miles north) and Edmonton (2 miles south-east). Larger places within reach include London (9 miles south), City of Westminster (9 miles south), Marylebone (8 miles south), Kensington (10 miles south-west), St Pancras (7 miles south) and Shoreditch (8 miles south).
Landmarks near Winchmore Hill
Typical jobs here are in homes near Winchmore School, Keble Preparatory School and The Kings Head pub and the streets around them. There’s a railway station in Winchmore Hill itself: Winchmore Hill station. Well-known places in the area include Museum of Enfield (1.4 miles north-east) and Edmonton Green Shopping Centre (1.9 miles east). The countryside around Winchmore Hill includes Darland's Lake and Barfield Allotments Nature Park.
When it isn’t the sealant
Honest advice matters more to us than a booking, so here’s what sealant cannot fix:
- Whether work needs listed building consent
- Sashes that rattle, stick or won’t open
- Broken panes
If you are not sure, just phone 0345 464 0079 or email us and we’ll give you a straight answer.
Surfaces we seal
- Period & listed homes
- Timber door frames
- Stone surrounds
- Sash and case windows
- Tenement windows
- Brick reveals
How it works
Once we are on site, we compare the joints with what we discussed. If we find something unexpected, we talk it through with you first. After that, the work takes anything from a few hours to a full day, depending on how many windows. In Winchmore Hill, flats, stairs and shared entrances are part of the routine. If the building has a concierge, managing agent or access rules, tell us when you book.
- We check each window surround and the condition of the joint.
- 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.
- We finish the mastic to a tidy line.
Getting ready for the visit
- On commercial sites, let us know about site rules
- Mention any parking rules near the property
- Clear items away from the joints we’re working on
Get a quote
For a quick quote, get us on the phone, or send an email if you’d rather. Describe what needs sealing and we will talk you through the work.
Advice
Landlord and commercial work in Winchmore Hill
We regularly work with letting and managing agents. Tell us the address, the job and how access works and we’ll quote.
Failed sealant is one of the commonest items on a check-out report, and it’s easy to sort out between tenants. We can quote for more than one property at once.
How we quote for sand mastic
Every job gets its own quote. These are the things that affect it:
- How much old sealant there is and how hard it is to remove
- Working hours on commercial sites
- The amount of work
- How many rooms, windows or areas are involved
No two jobs are quite the same, so we quote each one individually. The number of joints, how easy they are to reach and the sealant needed all play a part.
What to tell us for a quote
When you contact us, it’s useful to know:
- How many joints, rooms or windows are involved
- Any previous sealing or DIY work
- How we’d reach the joints
- What the problem is, such as mould, gaps, leaks or cracking
Want a quote for sand mastic? Please ring 0345 464 0079 or drop us an email with a few details. We’ll explain what we’d do and give you a clear price before any work starts.