Greater London · England
Window & door mastic in Three Mills, Greater London
Specialist window mastic for Three Mills: careful preparation, the right product and tidy work. Call for a quick quote.
- Black, perished sealant on frames
- Cracked internal joints between frame and plaster
- Leaking joints at the ends of sills
Keeping the joints in good condition
Good habits help new joints last longer. A few tips:
- Clean frames with a soft cloth and soapy water
- Ventilate rooms so frames don’t stay wet inside
- Keep timber frames painted
- Do not paint over the silicone
On timber frames, keep the paintwork in good order, since wood that gets wet swells and shrinks more. Keep paint off the silicone itself.
On timber windows, water behind the joint can lead to rot. Rotten timber needs a joiner, not a sealant, so it pays to reseal before that happens.
Window mastic in Three Mills
Over two decades of sealing frames has taught us which products suit which walls. We are fully insured ARBOMaster approved applicators, and we give a 12-month guarantee on the work. We work on aluminium frames, composite doors and uPVC windows, and common reasons people get in touch are gaps between the frame and the inside reveal and water coming in at the bottom corners of a door.
London’s Victorian and Edwardian terraces were built with timber sash windows, and many still have them or their replacements. Either way, the mastic between frame and brickwork is what stops draughts and rain getting in.
Your job is guaranteed for a year, as with all our work.
- Location
- Three Mills (E3, E15, E14)
- Wider area
- Greater London
- Cover
- One year on every job
- Quotes
- Quoted before any work starts
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
Surface by surface
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.
Window sills
Masonry sills can have joints where water gets in, including the one between the sill and the frame above. We seal those with a sealant suited to masonry.
When something else is needed
To be straight with you, there are a few things sealant will not fix:
- A frame that has rotted at the joint
- Damp coming through the wall itself rather than the frame joint
- A failed sealed unit that has misted up
If you are not sure, just phone 0345 464 0079 or send us an email and we’ll give you a straight answer before booking.
What we seal
- Aluminium frames
- uPVC windows
- Timber windows & doors
- Patio & French doors
- Composite doors
- Window sills
Also near Three Mills
What else we do in Three Mills
How we quote for window mastic
Jobs vary more than people expect. The main factors:
- Mould in or behind the old joints
- The size of the job
- How many rooms, windows or areas are involved
- How easy the joints are to reach
What you pay reflects the work, not a rough estimate. That’s why we ask a few questions first and send you a clear quote before we start.
Helping us quote
The more you tell us, the more accurate the quote. When you ask for a quote, tell us:
- Where the job is, and your postcode
- What the problem is, such as mould, gaps, leaks or cracking
- Whether it has been sealed before
- Photos by email, if that is easy
We do not publish a price list, because every job is different. Instead, your job gets its own clear quote. To get started, phone 0345 464 0079 or send us an email.
DIY sealant or a professional job?
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs call for the right materials, safe access and experience.
Windows and doors in Three Mills
With historic houses such as Sutton House (about 2.4 miles north-west) nearby, there’s older building stock in the area around Three Mills as well as newer homes. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that’s traditional sand mastic. In a converted house or block, who looks after the windows depends on the lease, so check that before you book.
Rented homes near West Ham station change hands often, and sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. If you look after a building such as East London Science School, its window and door frames need their mastic kept sound, just like a home’s. As a London address, Three Mills can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Three Mills is about 1 mile south of Stratford, in Greater London. From the centre of Three Mills to the outskirts, we cover window mastic for every kind of property. Our Greater London coverage runs to 764 places, Three Mills among them.
Work in E3, E15 and E14 is quoted and booked the same way as anywhere else. Streets in the area include Gay Road, Bruce Road and Edgar Road, all of which we cover. Neighbouring places we cover for window mastic include Mill Meads (1 mile north), Bromley (1 mile south-west), Old Ford (1 mile north-west), Bow (1 mile west) and Bow Common (1 mile south-west). Within a short drive, we also cover London (4 miles south-west), City of Westminster (6 miles west), Marylebone (6 miles west), Kensington (9 miles west), St Pancras (5 miles west) and Shoreditch (3 miles west).
Near you in Three Mills
Around Three Mills, our work takes us to homes and buildings near Manorfield Primary School, London International School of Performing Arts and Bob's Park, among other places. The closest station to Three Mills is West Ham station, about 0.5 miles east of the centre. A little further out are Stratford Centre (1 mile north) and St Clement's Hospital (0.9 miles west). For a walk, there’s Hollow Pond and Old Ford Island.
Questions from Three Mills
Is Three Mills in your area for window mastic?
Yes. Our work covers London and the South East, and Three Mills is part of that. Just phone 0345 464 0079 or send us an email with a few details of the job.
I let a flat near West Ham station. Can you help?
Yes, we work for landlords and agents. Just phone 0345 464 0079 or send us an email and tell us about the property, and we’ll send you a clear quote.
Will you leave a mess?
No. We protect the surfaces around the joints, and we tidy up before we go.
Will there be a smell?
Possibly a little. It fades as the sealant cures, and ventilation helps.
Is the new sealant paintable?
That depends on the product. Silicone isn’t paintable, but some hybrid sealants are. Mention any painting plans before any work starts.
Where is Mr Mastic based?
Our base is Crawley, with over 20 years’ experience. We work across South East England, London and Scotland.
Do you have sealant for grey or black windows?
Yes. We can use white, brown, anthracite grey, black or clear, so the joint suits the frame.
Can you do several jobs on one visit?
Of course. Combining jobs makes good use of the visit.
Leave it or put it right?
A quick bead over the top of old mastic looks like an easy fix, but new sealant can’t bond to old, crumbling mastic. It peels before long, and water still gets in behind. The old mastic has to come out. In a London flat, a failed joint rarely stays your problem alone: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
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 us?
- An ARBOMaster approved applicator
- Experience in homes, commercial sites and hotels
- We are fully insured
- We agree the colour with you first
Take a look at our cost guide and customer reviews.
What we do, step by step
Before we leave, we go over the finished joints with you. The work normally takes a few hours for a handful of frames, longer for a whole house, depending on how much there is to do. For a job in Three Mills, parking and access are the things to plan: let us know about parking, the floor we will be working on and any lift or shared entrance.
- We check how each frame can be reached safely.
- All the failed sealant is cut away, along with any loose debris.
- Frame and wall are cleaned and must be dry before sealing.
- Backing rod fills deep voids and the sealant goes in on top.
- We tool the joint so water runs off, then clear up.
Preparing for the visit
- Tell us about any previous sealing or DIY attempts
- Keep pets and children clear of the area while we work
- Clear the area around the work
Getting a quote
Asking for a quote is easy: let us know the job and the location and its rough size. Photos by email help us understand the job.