Greater London · England
Sand mastic for sash & case windows in Clapton, Greater London
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for householders, landlords and businesses in Clapton. Fully insured, ARBOMaster approved and guaranteed for a year.
- Silicone on a period window that looks wrong
- Mastic worn away on windows facing the weather
- Old sand mastic that has cracked, crumbled or fallen out
Sand mastic in Clapton
We renew sand mastic around sash windows and doors in stone and brick. Out comes the old, loose mastic, the joint is prepared and new mastic is shaped by hand. We are often asked to deal with gaps where the frame meets the masonry and cracked mastic round a front door frame, on brick reveals, stone surrounds and period & listed homes.
Many London homes are flats, with windows high above the street. Who looks after the outside of the frames can depend on the lease, so check that first, and access in Clapton is something to talk through when you book.
Your job is guaranteed for a year, as with all our work.
- Location
- Clapton (E5, N16, E8)
- Region
- Greater London
- Cover
- One year on every job
- Quotes
- A clear price before we start
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
What happens if it’s left?
New mastic over crumbling mastic won’t hold. We remove the loose material first so the new work lasts. In a flat in Clapton, failed sealant seldom stays inside your own four walls: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
There are no prices on our website, because the cost depends so much on the job itself. Call for a quick quote.
Why book with us
- 4.9 on Google from 180+ five-star reviews
- Old sealant always removed completely
- Anti-fungal silicone where joints get wet
- Homes, businesses and hotels
Take a look at our cost guide or customer reviews.
DIY versus a professional finish
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it fails, we can still redo it.
How to look after the new joints
How long the joints last depends on use and care. Here’s what we suggest:
- Renew mastic before redecorating the windows
- Check with your local planning authority if your home is listed
- Avoid patching sand mastic with silicone
- Make sure water runs off the sill
When preparing windows for paint, take care around the mastic. Hard scraping can loosen it.
It’s best to renew mastic before painting the windows. Painting over failed mastic hides the problem for a while.
What we can’t put right
Honest advice matters more to us than a booking, so here’s what sealant can’t fix:
- Damaged stone surrounds
- Whether work needs listed building consent
- Sashes that rattle, stick or will not open
Not sure which it is? You can call 0345 464 0079 or send us an email and we will tell you honestly before you book.
Surfaces we seal
- Timber door frames
- Stone surrounds
- Brick reveals
- Sash and case windows
- Tenement windows
- Period & listed homes
Signs you need sand mastic in Clapton
Shallow joints are a common cause. Mastic that is too thin cracks and drops out, which is why we pack deep voids first and get the depth right.
These are the problems we are asked about most:
- Patchy fillers round a sash window
- Mastic worn away on windows facing the weather
- Gaps between timber frames and stone or brick
- Tired mastic found when preparing windows for paint
Schools such as BSix Sixth Form College are buildings too, and its window and door frames need their mastic kept sound, just like a home’s.
Questions to ask before you book
- How long to leave it before use
- Is VAT in the price?
- Which colour the sealant will be
- Are they insured?
What the job involves on each surface
Sash and case windows
On a sash window, the mastic joint shows on the outside, so a neat, even finish matters.
Timber door frames
Doors face weather and wear and the mastic can crack early. We rake it out and renew it.
Common questions in Clapton
Do you work for landlords with property near Clapton station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. Just call 0345 464 0079 or drop us an email with the address and what needs doing, and we’ll give you a clear quote.
Is parking an issue for sand mastic in Clapton?
Parking in Clapton, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly.
Do you take out the old sealant first?
Yes, every time. New sealant won’t bond properly to old, so the joint is cleaned back first.
Should I use sand mastic or silicone?
That depends on your windows. Period windows in stone or brick generally suit sand mastic and newer frames normally get a flexible sealant.
Can I do it myself?
Sometimes. The key is preparation: remove all the old material and work on a clean, dry joint. We can always put it right if it fails.
Is it possible to paint over sand mastic?
Sand mastic is normally left unpainted, which is what traditional guidance recommends. Talk to us before any painting near it.
Is there any odour?
It depends on the product. Some smell for a while, some hardly at all.
Do you work in Clapton?
Yes. We work in Clapton and the rest of Greater London, as part of our work across South East England, London and Scotland. To book, ring 0345 464 0079 or email us.
Windows and doors in Clapton
Rainfall in the South East is lower than in much of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. In London conversions and blocks, the lease decides who is responsible for the frames, so check that before you book.
As a London address, Clapton can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. For landlords with property near Clapton station, older sash windows in a rental need their mastic kept sound to keep the weather out.
Clapton is about 2 miles east of Highbury, in Greater London. Every kind of property in Clapton is covered for sand mastic, old or new, large or small. The work is guaranteed for a year. Our area takes in 764 places across Greater London, large and small.
Our applicators cover all of E5, N16 and E8 for sand mastic and the streets around it. Whether your property is on Muir Road, Downs Road and Tilia Road or anywhere close by, our applicators can take on the job. Other places close to Clapton include Lea Bridge (1 mile north-east), West Hackney (1 mile west), Homerton (1 mile south-east), Lower Clapton (1 mile south-east) and Shacklewell (1 mile south-west). Within a short drive, we also cover London (4 miles south), City of Westminster (5 miles south-west), Marylebone (5 miles south-west), Kensington (7 miles south-west), St Pancras (3 miles south-west) and Whitechapel (3 miles south).
Near you in Clapton
Around Clapton, our work takes us to homes and buildings near The Amhurst Arms Public House, Baden-Powell School and Millfields Park, among other places. Clapton has its own railway station: Clapton station. Other landmarks nearby include Clowns Gallery-Museum (1.2 miles south-west) and Tower of London (3.6 miles south). Green spaces nearby include Dartmouth Park Hill and Hollow Pond.
What we do, step by step
On the day, there’s very little for you to do. Point us to the joints and we’ll get on with it. The job generally takes a few hours for a single window, longer for several from start to finish. For a job in Clapton, parking and access are the things to plan: tell us about permits, visitor bays or off-street space, which floor we’re working on and whether there’s a lift.
- Each surround is checked first.
- 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
- Clear items away from the joints we are working on
- Tell us about access, such as stairs, a lift or high-level joints
- Let us know about parking restrictions
How to get a quote
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is, and add photos by email if you can.