Greater London · England
Window & door mastic in Coldharbour, Greater London
Specialist window mastic for Coldharbour: the right sealant, proper preparation and a neat finish. Ask us for a quick quote.
- Whistling draughts around closed windows
- Draughty joints inside around the window
- Rushed sealant from a window installation
How the visit works
At the end, we look at the finished work together and explain the cure time. The visit itself normally takes anything from an hour or two to a full day, depending on how many frames there are, depending on how much there is to do. In Coldharbour, as in most of London, parking needs a little planning. It helps if you can point us to a visitor permit or a bay close to the door.
- First, we go round the frames with you and agree the list.
- The old mastic is cut out and scraped back to clean surfaces.
- Where the gap is deep, backing rod goes in first.
- The new sealant goes on in white, brown, anthracite grey, black or clear to suit.
- We tool each bead neatly and check every joint is closed.
How to prepare
- Clear the area around the work
- Tell us if parking is tricky
- Mention any tricky access
How to get a quote
We do not publish a price list, because every job is different. Instead, we give you a clear quote for your job. To get started, call 0345 464 0079 or drop us an email.
Related advice
Window mastic in Coldharbour, done properly
A cold draught around a closed window often comes from the frame edge. A new joint stops the air getting through. Where the air is getting in through the window itself, we’ll say so. If you’re dealing with black, perished sealant on frames and damp patches on the reveal after heavy rain, we can put it right, whatever the surface.
Many London homes are flats, with windows high above the street. In a converted house or block, the lease usually says who is responsible for the windows, so it’s worth checking before booking.
There’s a 12-month guarantee on every job, whatever its size.
- Place
- Coldharbour (E14, SE10, E22)
- Wider area
- Greater London
- Cover
- One year on every job
- Price
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Looking after it afterwards
Joint life depends on how it’s used and looked after. We suggest:
- Look round the frames every year or so
- Wipe condensation off the frames
- Do not paint over the silicone
- Do not aim a pressure washer at the joints
Have a look at the joints once a year, ideally after winter. Small splits are simple to catch before they leak.
On timber windows, water behind the joint can lead to rot. Rotten timber needs a joiner, not a sealant, so early resealing is worth it.
Leave it or put it right?
Choosing the product is half the job. Interior caulk and bathroom silicone are not made for exterior frame joints. An exterior, low-modulus sealant stays flexible in sun and frost. In London conversions, one flat’s bathroom is often above another flat’s ceiling, so a small leak from tired sealant can mean a neighbour’s ceiling and a lot of disruption. Putting it right early is much less trouble.
A failed joint rarely gets cheaper to fix by waiting. If you’re unsure, phone 0345 464 0079 or email us and we’ll give you an honest view and a quote.
Why book with us
- A choice of colours where the product allows
- Experience in homes, commercial sites and hotels
- Rated 4.9 stars on Google
- Approved under the ARBOMaster scheme
Landlords, agents and businesses in Coldharbour
If you manage several properties in or around Coldharbour, jobs at different addresses can be quoted together. Just tell us the addresses and what each one needs, and pictures by email help.
Failed sealant is one of the commonest items on a check-out report, and it’s easy to sort out between tenants. We can quote for more than one property at once.
Also near Coldharbour
More services for Coldharbour
Coldharbour: your questions answered
Can parking be tricky for a visit in Coldharbour?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. That way the visit can be planned around it.
Can you help a landlord with a rental near Canary Wharf station?
Yes, we work for landlords and agents. Just call 0345 464 0079 or drop us an email and tell us about the property, and we’ll give you a clear quote.
How long will my window job take?
Allow a morning for a couple of windows and a door. Access and how stubborn the old mastic is affect the time most.
Do you come to Coldharbour?
Yes, we do. Our applicators work in Coldharbour, and the service is the same as everywhere else.
Can you seal over the old sealant?
No, and we never do. It can look neat for a few weeks, but the new layer lifts away from the old one. Removing the old sealant completely is the only lasting way.
Can you do upstairs windows?
Yes, where they can be reached safely. Let us know about access when you ask for a quote so we can plan the job.
Will it make a mess?
We keep the work tidy. We protect what’s around the joints, and we clear up when we’re done.
Where do you work from?
Mr Mastic is based in Crawley. Our applicators cover Coldharbour.
What we cannot put right
It helps to know what we can’t do too:
- Penetrating damp from a failed cavity tray or render
- A sash or casement that won’t close properly
- Worn gaskets, brush seals or a door that has dropped
Not sure which it is? You can call 0345 464 0079 or email us and we’ll tell you honestly before booking.
Joints and surfaces we work on
- Composite doors
- Timber windows & doors
- uPVC windows
- Window sills
- Patio & French doors
- Aluminium frames
Can I do it myself?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and does not move well, and the joint depth matters as much as the finish.
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
What affects the quote in Coldharbour
For a quick quote, just ask. The main things that affect it are:
- The old material and how stubborn it is
- Access and height
- The number of rooms or windows
- The size of the job
Commercial jobs are quoted on the same basis as homes: the amount of work, the access and the products needed, plus any working-time requirements on site. Ask us for a quote and we will go through it with you.
What to tell us for a quote
You don’t need to know the technical terms. It helps if you can tell us:
- The problem you’ve noticed
- A few photos by email, if you can
- Any previous sealing or DIY work
- How many joints, rooms or windows are involved
Getting a quote is simple: let us know what needs doing and where. Photos by email help us understand the job, and we’ll take it from there.
What window mastic looks like in Coldharbour
In London conversions and blocks, the lease decides who is responsible for the frames, so check that before you book. With historic houses such as Queen's House (about 1.5 miles south) nearby, there’s older building stock in the area around Coldharbour as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
For landlords with property near Canary Wharf station, sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. As a London address, Coldharbour can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. Schools such as Woolmore Primary School are buildings too, and its window and door frames need their mastic kept sound, just like a home’s.
Coldharbour is about 2 miles north of Greenwich, in Greater London. Whether you’re in the middle of Coldharbour or further out, we cover window mastic for every kind of property. Across Greater London, we cover 764 places, and Coldharbour is one of them.
Work in E14, SE10 and E22 works the same way as everywhere else we cover. That includes homes and businesses on Canada Square, Simpson's Road and Amsterdam Road and the roads around them. Coldharbour is on the A1206 and A1261, which makes it straightforward to reach. Neighbouring places we cover for window mastic include Blackwall (1 mile north-east), London Docklands (1 mile west), Poplar (1 mile north-west), Canary Wharf (1 mile west) and Heron Quays (1 mile west). Larger places within reach include London (4 miles west), City of Westminster (6 miles west), Marylebone (6 miles west), Kensington (8 miles west), St Pancras (5 miles west) and Shoreditch (3 miles north-west).
Around Coldharbour
Locally, jobs take us to homes and businesses close to Canary Wharf College 3, Mudchute Park and Farm and Tower Hamlets College, among other places. The closest station to Coldharbour is Canary Wharf station, about 0.5 miles north-west of the centre. Well-known places in the area include Old Royal Naval College (1.3 miles south) and Poplar Hospital (0.6 miles north). Open spaces near Coldharbour include Tower Hill and Lavender Pond.