Greater London · England
Sand mastic for sash & case windows in Force Green, Greater London
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for Force Green, backed by a one-year guarantee. Call for a quick quote.
- Old cement repairs round a window that have failed
- Weathered mastic on the most exposed windows
- Mastic that needs renewing before redecorating
How we quote for sand mastic
Your quote is based on your job. We look at:
- Mould in or behind the old joints
- Access and height
- The number and length of the joints
- Which sealant suits the joint
We don’t show prices on the website, because the cost depends so much on the job itself. Call for a quick quote and we’ll talk you through it.
What to tell us for a quote
Photos by email are helpful but not essential. Please mention:
- What the problem is, such as mould, gaps, leaks or cracking
- Access, such as stairs, a lift or height
- If someone has resealed it before
- Pictures of the joints, sent by email
We don’t publish a price list, as no two jobs are quite the same. Instead, your job gets its own clear quote. To get started, phone 0345 464 0079 or email us.
Sand mastic in Force Green
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. We work on tenement windows, sash and case windows and period & listed homes, and the jobs we see most are open joints round the window box and failed mastic on an exposed elevation.
Much of London’s older housing was built with timber sash windows, some still in place and some long since replaced. Either way, the mastic between frame and brickwork is what stops draughts and rain getting in, in Force Green as anywhere.
The work is covered for a year after we finish. If anything is not right with it, phone 0345 464 0079 or email us.
- Place
- Force Green (TN16)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Quote
- A clear price before work begins
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Landlords, agents and businesses in Force Green
We also work for property managers and facilities teams. We can quote a run of properties together, and we’re fully insured.
Hotels need rooms back in use, so the work can be planned room by room. We have worked in hotels as well as homes and businesses.
What we’re called out for in Force Green
Shallow joints are a common cause. Mastic that’s too thin cracks and drops out so we make sure the new mastic is the right thickness.
Most people get in touch when they notice something like this:
- Cement or filler used on old window joints that has cracked
- Draughty sash windows at the surround
- Mastic dropping out of the joint
- Gaps where the frame meets the masonry
Force Green is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Questions to ask before you book
- Is the old sealant removed completely?
- Whether VAT is included
- Who turns up on the day
- Are they insured?
How the visit works
There’s no need to move everything out before we come, only the area right around the joints. We protect the rest, and the job takes a few hours per window, depending on the condition of the joints for a typical job. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- We look at the surrounds with you and agree the joints to renew.
- We remove the old, loose mastic.
- Deep gaps are packed so the mastic sits at the right depth.
- We apply the mastic by hand and shape it.
- We dress the finish so it sits neatly against the masonry.
Preparing for the visit
- Try not to wet indoor joints just before the visit
- Let us know about stairs, lifts or work at height
- Mention any parking rules near the property
How to get a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints, and email pictures if that is easy.
Related advice
Windows and doors in Force Green
With historic houses such as Quebec House (about 0.8 miles south) nearby, there’s older building stock in the area around Force Green as well as newer homes. Where a home is older, 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.
In the older streets around Church of St Mary the Virgin, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. For landlords with property near Oxted station, cracked sand mastic around sash windows lets in the draughts tenants complain about.
Force Green is about 5 miles west of Sevenoaks, in Greater London. We carry out sand mastic for householders, landlords and businesses in Force Green, as part of our work across Greater London. Our Greater London coverage runs to 764 places, and Force Green is one of them. For nearby work, see our Crawley page (16 miles or so).
All of TN16 is within our area for sand mastic. If you’re just outside Force Green, we cover Westerham (1 mile south), South Street (2 miles north-west), Moorhouse Bank (2 miles south-west), Tatsfield (2 miles north-west) and Titsey (2 miles west). We also work in nearby towns such as Orpington (7 miles north), New Cross (14 miles north), Thornton Heath (12 miles north-west), Croydon (10 miles north-west), East Dulwich (14 miles north-west) and Plumstead (14 miles north).
What’s near Force Green
Typical jobs here are in homes near The Olde House At Home Public House. For rail, the closest station is Oxted station, roughly 3.8 miles south-west. Nearby you’ll also find Tandridge Priory (2.7 miles south-west). The countryside around Force Green includes Dryhill Nature Reserve and Betsom's Hill.
How to look after the new joints
Simple care keeps the joints in good condition. Our advice:
- Don’t paint over the new mastic
- Take care around the mastic when scraping paint
- Find out about consent before window work on a listed home
- Keep sills and gutters clear so water drains away
Do not run silicone over the new mastic. If you see a crack, ask us to take a look rather than patching it.
Renewing mastic before redecorating saves doing it twice. Paint over cracked mastic only covers it up.
Towns and villages near Force Green
Other services in Force Green
What sealant work cannot fix
Honest advice matters more to us than a booking, so here’s what new sealant won’t do:
- Sashes that rattle, stick or won’t open
- Crumbling stone or brickwork round the window
- Cracked or broken glass
If in doubt, call 0345 464 0079 or send us an email and we will say what we think before you book.
Joints and surfaces we work on
- Sash and case windows
- Stone surrounds
- Timber door frames
- Tenement windows
- Period & listed homes
- Brick reveals
How the job changes by surface
Sash and case windows
Most of our sand mastic work is on sash windows. We renew the mastic round each box.
Timber door frames
Sand mastic is used round timber door frames too. The method is the same as for windows.
Common questions in Force Green
Can you do sand mastic in Force Green?
Yes, Force Green is within the area we cover. Our work covers London and the South East. Just call 0345 464 0079 or send us an email with a few details of the job.
Can parking be tricky for a visit in Force Green?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
Can you replace silicone on a period window with sand mastic?
Generally, yes. With the silicone removed and the joint cleaned, sand mastic is applied by hand.
I’m a tenant. Can you help?
Yes, though it’s best to check with your landlord first. Many landlords are glad to have it sorted.
What should I tell you?
The location, the problem and the rough size of the job. If you can, email a few pictures.
Is it OK to seal over old sealant?
No, and we never do. It can look neat for a few weeks, but the new bead soon lifts. Removing the old sealant completely is the only lasting way.
Can you work on commercial sites?
Yes. We work in offices, washrooms, hotels and other commercial premises. We can talk about working times when we quote.
How long does sand mastic take to go off?
A skin forms quite soon, but full hardening takes longer. We will tell you what to expect for your job.