Greater London · England
Sand mastic for sash & case windows in West Brompton, Greater London
Window and door surrounds in West Brompton need attention? We cut out the old, prepare the joints and apply the right sealant, with a 12-month guarantee.
- Mastic round period door frames that has failed
- Old sand mastic that has cracked, crumbled or fallen out
- Mastic worn away on windows facing the weather
Sand mastic in West Brompton
Sand mastic skins over fairly quickly but full hardening takes longer. Traditionally, sand mastic is left unpainted and we’ll advise if you are redecorating. We work on timber door frames, period & listed homes and brick reveals, and people most often call us about mastic dropping out of the joint and gaps round a timber door in stone or brick.
From mansion-block windows to modern glazing in new flats, London has every kind of frame. Over the years, the sealant around them shrinks, cracks and pulls away, letting in draughts and water.
The work is covered for a year after we finish. If there’s a problem with it, please phone 0345 464 0079 or send us an email.
- Location
- West Brompton (SW6, SW10, SW5)
- Region
- Greater London
- Guarantee
- One year on every job
- Quotes
- A clear price before work begins
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
DIY versus a professional finish
Overfilling a joint is a classic DIY mistake. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
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.
Common questions in West Brompton
Can parking be tricky for a visit in West Brompton?
Parking in West Brompton, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly.
Do you cover West Brompton for sand mastic?
Yes. We work across London and the South East, and West Brompton is part of that. You can phone 0345 464 0079 or drop us an email and tell us what needs doing.
Can old silicone round a sash window be swapped for sand mastic?
Often, yes. Once the silicone is out and the joint prepared, sand mastic is applied by hand.
How long does sand mastic take?
That depends on the amount of work, but most jobs take anything from a few hours to a full day, depending on how many windows. We will tell you when we quote.
Can you seal over the old sealant?
No. New silicone will not bond to old silicone, and anything trapped underneath, including mould and water, stays there. We remove it all first.
Are you an approved applicator?
Yes. We are ARBOMaster approved, the scheme for applicators of Arbo sealants.
Will there be a smell?
Some sealants have a smell while they cure, but it fades. Ventilation helps.
Do you do commercial work?
Yes. Hotels, offices and other businesses use us, and we are fully insured.
West Brompton homes and the weather
Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. In London conversions and blocks, the lease decides who is responsible for the frames, so it’s worth checking before booking.
As a London address, West Brompton can be tricky for parking: let us know about parking bays, permits or a driveway. In the older streets around Church of St Luke, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
West Brompton is about 1 mile south of Kensington, in Greater London. Every kind of property in West Brompton is covered for sand mastic, old or new, large or small. The work is guaranteed for a year. Across Greater London, we cover 764 places, and West Brompton is one of them.
Postcode districts we cover here for sand mastic: SW6, SW10 and SW5. If you need sand mastic at a property on Sun Road, Star Road and Farm Lane or a nearby road, our applicators can take on the job. Being close to the A3218 and A3220, West Brompton is easy for our applicators to reach for sand mastic. Other places close to West Brompton include Earl's Court (1 mile north), Walham Green (1 mile south), World's End (1 mile south-east), Little Chelsea (1 mile east) and South Kensington (1 mile north-east). Within a short drive, we also cover London (4 miles east), City of Westminster (3 miles north-east), Marylebone (3 miles north-east), St Pancras (4 miles north-east), Shoreditch (6 miles north-east) and Walthamstow (10 miles north-east).
What’s near West Brompton
Around West Brompton, our work takes us to homes and buildings near The London Oratory School, The Fulham Boys School and Gwendwr Garden, among other places. Other local landmarks include Natural History Museum Library and Archives (1.1 miles north-east) and Coleherne public house (under half a mile north-east). West Brompton has its own railway station: West Brompton station. Nearby you’ll also find Kensington Arcade (1 mile north) and Chelsea Stadium Tour And Museum (within half a mile south-east). For a walk, there’s The Long Water and WWT London Wetland Centre.
Looking after it afterwards
No joint lasts for ever, but care makes a real difference. Our tips:
- Get any rot dealt with first
- Don’t paint over the new mastic
- Plan mastic work ahead of painting
- Avoid patching sand mastic with silicone
When preparing windows for paint, take care around the mastic. It can be damaged by heavy scraping.
Small cracks are a sign the mastic is ageing. It’s easier to renew it before it drops out.
Nearby places to West Brompton
Also in West Brompton
What we cannot put right
A few problems are outside what sealant work can do:
- Whether work needs listed building consent
- Timber that has rotted
- Putty and glazing repairs
Not sure which it is? You can ring 0345 464 0079 or send us an email and we will tell you honestly.
Joints and surfaces we work on
- Period & listed homes
- Tenement windows
- Stone surrounds
- Brick reveals
- Sash and case windows
- Timber door frames
How we quote for sand mastic
For a quick quote, just ask. What matters most is:
- Which sealant suits the joint
- Whether the work is at height
- The size of the job
- Whether old sealant or filler has to be cut out
The cost depends on the size of the job, how hard the old material is to remove and access to the work. We give a clear quote before any work starts.
Helping us quote
Photos by email are helpful but not essential. Try to tell us:
- Any previous sealing or DIY work
- The problem you’ve noticed
- Pictures of the joints, sent by email
- Any access issues, like height or stairs
Need a quote? Please call 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 work begins.
What happens on the day
You don’t need to clear the whole room or building, just the space around the work. Everything nearby is protected, and the job takes a few hours per window, depending on the condition of the joints for a typical job. In West Brompton, 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 the window surrounds and agree which joints need renewing.
- We rake out the old mastic and clean the joint.
- We pack any deep gaps so the mastic sits at the right depth.
- The mastic is mixed, pressed into the joint by hand and shaped.
- The finish is dressed so it sits neatly against the stone or brick.
Getting ready for the visit
- Keep children and pets away from the work area
- Clear the area around the work
- For business premises, tell us about site rules or sign-in
Ask for 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’ll talk you through the work.
Related advice
When to call us in West Brompton
Shallow joints are a common cause. Mastic that is too thin cracks and drops out so we make sure the new mastic is the right thickness.
If you can see any of these, it’s time to have the joints looked at:
- Draughts and rain around sash boxes
- Gaps between timber frames and stone or brick
- Cement or filler used on old window joints that has cracked
- Cracked mastic round a front door frame
If you let a flat or house near West Brompton station, cracked sand mastic around sash windows lets in the draughts tenants complain about.
Questions to ask before booking
- Whether they seal over old material or remove it
- Whether you can choose the colour
- How hidden problems are handled
- Whether the sealant suits the joint
Landlords, agents and businesses in West Brompton
Failed sealant is one of the commonest items on a check-out report. Several properties can go on one quote.
Hotels need rooms back in use, so we plan the work room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.