Greater London · England
Window & door mastic in Bow, Greater London
Window mastic for Bow, by sealant specialists with 20+ years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Draughty joints inside around the window
- Black, perished sealant on frames
- A bead that doesn’t match the frame
How we handle window mastic in Bow
The new joint does not have to be white. White, brown, anthracite grey, black and clear sealants are all available, so the bead blends with the window rather than framing it. We work on composite doors, window sills and patio & French doors, and the jobs we see most are black, perished sealant on frames and gaps where the sill meets the wall.
From mansion-block windows to modern glazing in new flats, London has every kind of frame. The mastic around them dries out and cracks with age, letting in draughts and water.
We stand behind the work with a one-year guarantee, so you’re covered after we’ve gone.
- Where
- Bow (E3)
- Region
- Greater London
- Guarantee
- One year on every job
- Quotes
- A clear quote up front
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Signs you need window mastic in Bow
Sills take more water than any other part of a window, and the ends of the sill, where it meets the wall, are where it gets in. When that sealant fails, water gets into the wall or under the frame.
Look out for these signs:
- Damp patches on the reveal after heavy rain
- Black, perished sealant on frames
- Gaps left after new windows were fitted
- Cracked or shrunken mastic around the frame
Rented homes near Hackney Wick station change hands often, and sound mastic around windows and doors keeps out the draughts and damp that tenants notice first.
What your quote should include
- How the joint is cleaned and prepared
- Are they insured?
- Whether they seal over old material or remove it
- What guarantee comes with the work
How to look after the new joints
Good habits help new joints last longer. Our tips:
- Use gentle cleaners on frames and sealant
- Check the mastic once a year
- Keep timber frames painted
- Keep drainage slots and sill grooves clear
Wipe the frames with soapy water when you clean the windows, and keep solvents and harsh chemicals off the joint.
Water gets in quietly when mastic fails. Often the first sign is a damp patch inside or flaking paint on the reveal. Early resealing stops it reaching that point.
Surface by surface
Window sills
Sills catch the water running down the glass, so the joints at each end and underneath matter. They’re cut out and resealed with exterior sealant.
Aluminium frames
Coated aluminium needs a compatible sealant and we avoid acetoxy silicones, which can react with some metals. Neutral-cure sealant is the safe choice.
DIY versus a professional finish
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
What we do, step by step
There is not much for you to do on the day. Show us the job and we’ll take it from there. The job generally takes a few hours for a few frames, or a day or more for a whole house. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. Mention any building rules, key holders or managing agents when you book.
- We check each frame and agree which ones need doing.
- We remove the old mastic and clean the frame and the wall.
- Deep gaps are filled with backing rod to set the depth.
- New exterior sealant goes on in a matching colour and is tooled smooth.
- Every joint is checked before we leave.
How to prepare
- Tell us about any water getting in
- Keep pets and children clear of the area while we work
- Mention any parking rules near the property
Ask for a quote
Asking for a quote is easy: tell us what needs doing and where and its rough size. Photos by email help us understand the job, and we’ll come back to you with a quote.
Read more
Work for landlords, hotels and businesses
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.
We also work for property managers and facilities teams. We can quote a run of properties together, and we’re fully insured.
Honest limits
Sealant is not the answer to every problem, and we’d rather say so up front. It won’t solve:
- Faulty window hardware
- Rotten timber, which needs a joiner first
- Draughts through the window seals rather than the frame
Not sure which it is? You can phone 0345 464 0079 or send us an email and we’ll tell you honestly.
Surfaces we seal
- Aluminium frames
- Patio & French doors
- Composite doors
- Window sills
- uPVC windows
- Timber windows & doors
Bow homes and the weather
With historic houses such as Sutton House (about 1.6 miles north-west) nearby, there’s older building stock in the area around Bow as well as newer homes. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that’s traditional sand mastic. 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 the older streets around St Paul Old Ford, the joint between an old wall and a newer frame is generally the first place rain gets in. For site and facilities teams at buildings such as Old Ford Primary - A Paradigm Academy, its window and door frames need their mastic kept sound, just like a home’s.
Bow is about 1 mile south-east of Hackney, in Greater London. For window mastic in and around Bow, please call 0345 464 0079 or drop us an email for a quick quote. We cover Greater London from our Crawley base. Across Greater London, we cover 764 places, Bow among them.
We cover every part of E3 for window mastic and the streets around it. Whether your property is on Trellis Square, Sheffield Square and Bromley High Street or a nearby road, our applicators can take on the job. Bow sits on or near the B142, which makes travel easy. Other places close to Bow include Donnybrook Quarter (1 mile north), Old Ford (1 mile north-east), Mile End (1 mile south), Fish Island (1 mile north) and Bromley (1 mile south-east). Further out, we also cover London (4 miles south-west), City of Westminster (6 miles west), Marylebone (5 miles west), Kensington (8 miles west), St Pancras (4 miles west) and Walthamstow (4 miles north).
Around Bow
Typical jobs here are in homes near Lord Tredegar Public House, Grove Hall Park and Mulberry UTC and the streets around them. The nearest railway station is Hackney Wick station, about 0.9 miles north. Nearby you will also find V&A East (0.9 miles north-east) and St Clement's Hospital (within half a mile south). Not far away are Hollow Pond and Old Ford Island.
Your questions about window mastic in Bow
Is Bow in your area for window mastic?
Yes. Our work covers London and the South East, and Bow is part of that. You can phone 0345 464 0079 or drop us an email and let us know what needs doing.
Do you work for landlords with property near Hackney Wick station?
Yes, rental work is part of what we do. Just call 0345 464 0079 or send us an email and tell us about the property, and we will send you a clear quote.
What information do you need?
Only a few details: the address or postcode, what’s wrong and any access issues. Then phone 0345 464 0079 or email us.
Can you match the sealant to my frames?
Yes, we choose a colour to suit the frame. Anthracite grey, black, brown and white cover most frames, with clear as an option.
Will new mastic stop draughts?
Yes, if the air is getting in around the frame. If it’s through the window’s own seals or a hinge, that’s a different fix, and we’ll say so.
Can you work on commercial sites?
Yes. We’ve worked for hotels, offices and other businesses.
How long should I leave it?
Many sealants skin over quickly but take longer to cure fully. We will give you the cure time for the product we used.
How long does it take to reseal the windows on a house?
The work takes a few hours for a handful of frames, longer for a whole house. Access and the amount of old mastic make the biggest difference.