Greater London · England
Sand mastic for sash & case windows in Charlton, Greater London
Professional sand mastic in and around Charlton, with old sealant always removed completely and a one-year guarantee.
- Old sand mastic that has cracked, crumbled or fallen out
- Weathered mastic on the most exposed windows
- Patchy fillers round a sash window
Sand mastic for homes and businesses in Charlton
For a listed home or one in a conservation area, ask your local planning authority whether consent is needed for work to windows. Sand mastic is often favoured as a like-for-like material. If you have open joints round the window box and weathered mastic on the most exposed windows, we can help, on stone surrounds, sash and case windows and timber door frames alike.
London’s Victorian and Edwardian terraces were built with timber sash windows, and many still have them or their replacements. Whatever is in the opening now, the joint between frame and wall is what keeps the weather out, in Charlton as anywhere.
All our work comes with a 12-month guarantee.
- Location
- Charlton (SE7, SE18)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
How to look after the new joints
A little care helps the new joints last. We recommend:
- Inspect the joints round the windows every year or so
- Take care around the mastic when scraping paint
- Get any rot dealt with first
- Find out about consent before window work on a listed home
Leave the new mastic alone while it firms up. It forms a skin fairly soon, but takes longer to harden fully.
Sound mastic protects the frame. Failed mastic lets water reach the timber, which can lead to rot.
Towns and villages near Charlton
More services for Charlton
When it isn’t the sealant
We will not take on work that will not last, so here’s what sealant cannot put right:
- Sashes that need overhauling
- Timber that has rotted
- Cracked or broken glass
If you are not sure, just call 0345 464 0079 or email us and we will give you a straight answer.
Where we work in Charlton
- Brick reveals
- Tenement windows
- Sash and case windows
- Stone surrounds
- Timber door frames
- Period & listed homes
Charlton homes and the weather
In London conversions and blocks, the lease decides who is responsible for the frames, so check that before you book. Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
As a London address, Charlton can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. For landlords with property near Charlton station, older sash windows in a rental need their mastic kept sound to keep the weather out.
Charlton is about 2 miles west of Plumstead, in Greater London. Anywhere in SE7, we can carry out sand mastic at your property. Charlton is one of 764 towns and villages in Greater London where we work. London is on our list too, around 6 miles away.
We cover every part of SE7 and SE18 for sand mastic. Streets in the area include Floyd Road, Guild Road and Priolo Road, and we cover them all. Other places close to Charlton include New Charlton (1 mile north-west), Westcombe Park (1 mile west), Woolwich (1 mile east), Vanbrugh Park Estate (1 mile south-west) and Kidbrooke (2 miles south). We also work in nearby towns such as London (6 miles west), City of Westminster (8 miles west), Marylebone (8 miles west), Kensington (10 miles west), St Pancras (7 miles west) and Shoreditch (6 miles north-west).
Near you in Charlton
Typical jobs here are in homes near Charlton Park, Wildwood Montessori School and Royal Greenwich Trust School. Charlton has its own railway station: Charlton station. Nearby you’ll also find British Hospital for Mothers and Babies (0.5 miles east) and Gallions Reach Shopping Park (2.3 miles north-east). Open spaces near Charlton include Gilbert's Pit.
What happens if it’s left?
If you are redecorating, renew the mastic first. Paint over cracked mastic will not stop the gaps, and the new mastic is traditionally left unpainted. Damp from a failed joint spreads quietly in older London brickwork and timber, and once it shows in Charlton, the repair is bigger than a sealant job.
A few things move the cost up or down: how much old sealant there is and how stubborn it is, whether mould needs treating, and whether the work is at height. Your quote takes all of that into account.
Why choose Mr Mastic in Charlton
- Arbo and Everbuild products
- Domestic, commercial and hotel work
- 12-month guarantee on every job
- Full insurance on every job
Take a look at our cost guide or customer reviews.
Your questions about sand mastic in Charlton
Do you work for landlords with property near Charlton station?
Yes, landlords and agents are among the people we work for. Just call 0345 464 0079 or email us with the address and what needs doing, and we will give you a clear price.
Is Charlton in your area for sand mastic?
Yes. We work across London and the South East, and Charlton is part of that. Just phone 0345 464 0079 or email us with a few details of the job.
Do I need to be at home?
Access is agreed with you when the job is booked. For inside work, that normally means someone being in.
What sealant do you use?
Quality sealants from brands including Arbo and Everbuild, picked for each joint. We explain the product when we quote.
Can you quote for more than one area?
Yes. More than one area can be quoted together.
Where are you based?
Our base is in Crawley, West Sussex, and we cover South East England, London and all of Scotland.
Can I paint the new mastic?
Traditional guidance is not to paint over sand mastic. If you’re redecorating the window, ask us first and we’ll advise.
What’s sand mastic made of?
Sand mastic is a traditional material for pointing round windows and doors. It’s made with sand and a linseed-oil-based binder.
Do you need sand mastic in Charlton?
Most of it is simply age. Even well-laid mastic needs renewing in time, depending on exposure and upkeep.
Look out for these signs:
- Gaps where the frame meets the masonry
- Old sand mastic that has cracked, crumbled or fallen out
- Mastic that needs renewing before redecorating
- Mastic round period door frames that has failed
Managing a site like Thorntree Primary School? Then the mastic around its windows and doors needs looking after like any other building’s.
Before you book anyone
- What guarantee comes with the work
- Whether VAT is included
- When the joint can take water or movement
- Which colour the sealant will be
The process
When we arrive, we look over the joints with you first. We protect the surfaces around the joints before any work begins. Most jobs take a few hours for a single window, longer for several. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Charlton. It helps if you can point us to a visitor permit or a bay close to the door.
- First, we look at the surrounds with you and agree what needs doing.
- Old, loose mastic is raked out and the joint cleaned.
- Deep voids are packed so the mastic is the right thickness.
- We mix the sand mastic and apply it by hand, shaping it to the joint.
- We dress the surface so it sits neatly against the masonry.
Preparing for the visit
- Keep children and pets away from the work area
- Mention any parking rules near the property
- Let us know about stairs, lifts or work at height
Getting a quote
For sand mastic in Charlton, phone 0345 464 0079 or send us an email. Tell us what the problem is and where, and you’ll get a clear quote before we start.
Advice
Landlord and commercial work in Charlton
Letting agents and landlords in Charlton can book us as well as householders. Sealant work between tenants is a simple way to keep a property in good order.
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
What affects the quote in Charlton
Some jobs are bigger than they look, and some smaller. The main factors:
- Any mould that needs treating
- Working hours on commercial sites
- The number and length of the joints
- How many areas need sealing
Commercial jobs are quoted on the same basis as homes: how much there is to do, how we reach it and what it needs, plus any working-time requirements on site. Ask us for a quote and we will explain what it covers.
Asking for a quote
When you contact us, it’s useful to know:
- Any access issues, like height or stairs
- Where the job is, and your postcode
- Photos by email, if that is easy
- Whether it’s a home or a business
We do not publish a price list. Instead, we give you a clear quote for your job. To get started, call 0345 464 0079 or send us an email.