Greater London · England
Window Mastic in Greenwich
Mastic around window and door frames, sills and patio doors in Greenwich, with a 12-month guarantee on every job. Call for a quick quote.
- Gaps between the frame and the inside reveal
- Rain getting in at the frame or under the sill
- Gaps where the sill meets the wall
What we cannot put right
Honest advice matters more to us than a booking, so here’s what new sealant won’t do:
- A frame that has rotted at the joint
- Faulty window hardware
- Damp coming through the wall itself rather than the frame joint
If you are not sure, just ring 0345 464 0079 or email us and we will give you a straight answer before you book.
Joints and surfaces we work on
- Window sills
- Aluminium frames
- Timber windows & doors
- uPVC windows
- Composite doors
- Patio & French doors
Window mastic in Greenwich
The new joint does not have to be white. We can seal in white, brown, anthracite grey, black or clear, so the bead blends with the window rather than framing it. If you have whistling draughts around closed windows and cracked sealant at the sill ends, we can put it right, on patio & French doors, aluminium frames and timber windows & doors alike.
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.
We guarantee the work for a year. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Location
- Greenwich (SE10, SE3, SE8)
- Wider area
- Greater London
- Guarantee
- A year, on every job
- Price
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
How we quote for window mastic
We don’t publish a price list. What we look at:
- How many rooms, windows or areas are involved
- Whether there’s mould to deal with
- How much old sealant there is and how hard it is to remove
- How easy the joints are to reach
A few things move the cost up or down: the old material and how easily it comes out, whether mould needs treating, and whether we need extra access for height. Your quote takes all of that into account.
Asking for a quote
What to tell us when you ask for a quote:
- If someone has resealed it before
- How we’d reach the joints
- Whether it’s a home or a business
- Where the property is
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.
Why act early in Greenwich
Draughts and leaks don’t always mean new windows. If the frames and glass are in good order, resealing the joints is often all that is needed. Problems with the glass or gaskets are for a window company, and we will say so. 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 Greenwich, the repair is bigger than the sealant job would have been.
Every job is a little different, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all make a difference, and we’ll explain the quote if you ask.
Why choose Mr Mastic in Greenwich
- Arbo and Everbuild products
- Colour agreed with you before we start
- A sealant colour to suit the surroundings
- Fully insured
Greenwich questions
Can you do window mastic in Greenwich?
Yes. We work across London and the South East, and Greenwich is part of that. You can phone 0345 464 0079 or send us an email and tell us what needs doing, and we’ll give you a clear price.
Do you work for landlords with property near Maze Hill station?
Yes. We work for letting agents and landlords as well as householders, and several properties can go on one quote. You can ring 0345 464 0079 or email us with the details for a clear quote.
What do you put in the joint?
Products from Arbo and Everbuild, among others, picked for each joint. We’ll tell you what we’re using and why.
What should I tell you?
Just the basics: where it is, what you’ve noticed and how we reach it. After that, simply ring 0345 464 0079 or drop us an email.
Do I need to be at home?
We need access to the joints, so we will agree that with you when we book. Indoors, that generally means someone at home.
Do you remove the old sealant?
Yes, every time. New silicone doesn’t stick to old silicone, so the joint is cleaned back first.
Can you quote for more than one area?
Yes, and it often makes sense. Combining jobs makes good use of the visit.
Do the sealants smell?
There can be a smell while the sealant cures, which fades as it sets. Opening a window helps.
Also near Greenwich
Other services in Greenwich
Landlord and commercial work in Greenwich
If you manage several properties in or around Greenwich, several properties can go on one quote. Send us the addresses and the work at each.
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements and we’ll give you a quote.
Aftercare tips
After the cure time, these simple habits help:
- Keep jet washers away from the mastic
- Make sure the drainage slots aren’t blocked
- Repaint timber before it’s bare
- Avoid harsh chemicals near the mastic
On timber frames, keep the paintwork in good order, because bare, wet timber moves more and pulls at the joint. Keep paint off the silicone itself.
Look out for the warning signs: cracks in the mastic, gaps you can see light through, damp on the reveal or mould around the inside of the frame. If you notice one, it’s time to get the joint looked at.
Frames and glazing around Greenwich
London and the South East are among the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. In a converted house or block, who looks after the windows depends on the lease, so it’s worth checking before booking.
As a London address, Greenwich can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. Schools such as Meridian Primary School are buildings too, and its window and door frames need their mastic kept sound, just like a home’s. Rented homes near Maze Hill station change hands often, and cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets.
Greenwich is about 4 miles east of London, in Greater London. From the centre of Greenwich to the outskirts, window mastic is available for homes and businesses alike, from flats and houses to offices and hotels. Our area takes in 764 places across Greater London.
We cover every part of SE10, SE3 and SE8 for window mastic and the streets around it. That includes homes and businesses on Cade Road, Webb Road and Creek Road. Main roads around Greenwich include the A2203 and A2211. Neighbouring places we cover for window mastic include Maze Hill (1 mile north-east), Vanbrugh Park Estate (1 mile east), Blackheath (1 mile south-east), Westcombe Park (1 mile east) and Isle of Dogs (1 mile north-west). We also work in nearby towns such as London (4 miles west), City of Westminster (7 miles west), Marylebone (7 miles west), Kensington (9 miles west), St Pancras (6 miles north-west) and Shoreditch (5 miles north-west).
Local landmarks in Greenwich
Around Greenwich, our work takes us to homes and buildings near The Plume of Feathers pub, John Roan School and Royal School of Naval Architecture and Marine Engineering and the streets around them. Other local landmarks include Island Gardens (0.6 miles north-west) and St. Paul's (1.1 miles west). Greenwich has its own railway station: Maze Hill station. Other landmarks nearby include Greenwich Castle (under half a mile south-west) and Greenwich District Hospital (0.5 miles north-east). Not far away are Tower Hill and Creekside Discovery Centre.
Should I try it myself first?
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. Everything old must be removed first.
If you’ve already had a go yourself, that is fine. We cut it out and start again.
What we do, step by step
Good joint work is mostly preparation, and we don’t rush it. Joints are cleaned back and dried before anything new goes in. In total, it normally takes a few hours for a handful of frames, longer for a whole house. In Greenwich, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- First, we go round the frames with you and agree the list.
- We remove the old mastic and clean the frame edge and wall.
- Where the gap is deep, backing rod goes in first.
- A flexible exterior sealant is applied in a colour to suit the frame.
- Every joint is tooled smooth and checked before we leave.
Getting ready for the visit
- Clear items away from the joints we’re working on
- On commercial sites, let us know about site rules
- Plan for the work area to be out of bounds to pets and children
Get a quote
A good description makes for an accurate quote. Tell us where the job is, what’s wrong and how much there is, and add photos by email if you can.