Greater London · England
Window & door mastic in Cowley, Greater London
Professional window mastic in and around Cowley, with every bit of old sealant taken out first and a 12-month guarantee.
- White mastic on grey or black frames
- Leaking joints at the ends of sills
- Hard, cracked sealant around windows
Window mastic in Cowley
A cold draught around a closed window often comes from the frame edge. A new joint stops the air getting through. If the draught is through the window seals instead, we will tell you. We work on uPVC windows, timber windows & doors and composite doors, and the jobs we see most are cold air getting in at the frame edge and cracked internal joints between frame and plaster.
Much of London’s older housing was built with timber sash windows, some still in place and some long since replaced. Whatever is in the opening now, the joint between frame and wall is what keeps the weather out.
All our work is covered by our one-year guarantee, wherever you are in Greater London.
- Location
- Cowley (UB8, UB7, UB10)
- Region
- Greater London
- Guarantee
- One year on every job
- Quotes
- A clear quote up front
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Honest limits
Sealant isn’t the answer to every problem, and we’d rather say so up front. Sealant won’t put right:
- Penetrating damp from a failed cavity tray or render
- Broken hinges, locks or handles
- Misting between the panes of a double-glazed unit (that needs a new unit)
Not sure which it is? You can phone 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
- Aluminium frames
- Patio & French doors
- uPVC windows
- Window sills
How the visit works
At the end, we look at the finished work together and explain the cure time. The visit itself normally takes most of a day for a typical house, less for a few frames, depending on the size of the 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.
- Each frame is looked over and we agree which ones need resealing.
- The old mastic is cut out and scraped back to clean surfaces.
- Where the gap is deep, backing rod goes in first.
- A flexible exterior sealant is applied in a colour to suit the frame.
- We tool each bead neatly and check every joint is closed.
Before we arrive
- Mention any sign-in or site rules at work premises
- Tell us about access, such as stairs, a lift or high-level joints
- Where the joints are inside, avoid wetting them before we arrive
Ask for a quote
Every job is quoted individually. Just ring 0345 464 0079 or send us an email with the details, and pictures are welcome.
Advice
DIY sealant or a professional job?
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
If you do try it yourself, take your time over the preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it doesn’t work out, we can still put it right.
Landlord and commercial work in Cowley
Letting agents often deal with us directly. Tell us the address, the job and how access works and we will quote.
Mouldy or split sealant often shows up at the end of a tenancy, and it’s quick to put right between tenancies. Several properties can go on one quote.
Cowley: your questions answered
Do you cover Cowley for window mastic?
Yes. We work across London and the South East, and Cowley is part of that. Just ring 0345 464 0079 or email us with a few details of the job.
Can you help a landlord with a rental near West Drayton 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’ll give you a clear price.
Can you reach windows above the ground floor?
Yes, as long as they can be reached safely. Tell us about access when you get in touch so we can plan the job.
What do you put in the joint?
We choose the sealant for the joint, not the other way round. Where it moves, gets wet or faces the weather makes a difference, and we will explain our choice.
Where do you work from?
We are based in Crawley, West Sussex, and we work across South East England, London and Scotland.
Is the work guaranteed?
Yes. Every job comes with our one-year guarantee, and we are ARBOMaster approved applicators.
Do you take out the old sealant first?
Yes, every time. New silicone doesn’t stick to old silicone, so any old material comes out before anything new goes in.
Are you fully insured?
Yes. We’re fully insured.
Surface by surface
uPVC windows
Plastic frames move a lot between a hot afternoon and a cold night, so the joint needs a low-modulus sealant that stays flexible. We match white, brown, anthracite grey and black frames.
Composite doors
A composite door generally sits in a plastic outer frame, and the joint around it is sealed like a window. The bead is colour-matched to the frame.
Signs you need window mastic in Cowley
Plenty of failed mastic was poorly applied in the first place. Mastic laid onto dusty, damp or crumbling surfaces didn’t grip properly, and it lets go sooner than it should.
Signs it’s time to call us include:
- Cold air getting in at the frame edge
- Rushed sealant from a window installation
- Cracked or shrunken mastic around the frame
- Rain getting in at the frame or under the sill
Cowley is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Before you book anyone
- When the joint can take water or movement
- Is VAT in the price?
- Which colour the sealant will be
- What happens if they find a problem under the old sealant
What happens if it’s left?
Working on frames from a ladder with a sealant gun is not easy, especially on upper floors. A professional job is cut out properly, backed where needed and finished neatly, in a sealant suited to the wall. Converted houses in London often have a bathroom above someone else’s living room, and a slow leak from a failed seal can end up in the flat below. Putting it right early is much less trouble for homes in Cowley.
Instead of a standard rate, we look at what your job involves: the amount of work, the old material and the access. You’ll know the price before we begin.
What you get with us
- We leave the area clean and tidy
- Anti-fungal sanitary silicone in wet areas
- Experience in homes, commercial sites and hotels
- A 12-month guarantee on all work
Read how sealant jobs are priced or our reviews.
Windows and doors in Cowley
In a converted house or block, who looks after the windows depends on the lease, so it’s worth checking before booking. The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
For landlords with property near West Drayton station, sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. In the older streets around Church of St Laurence, the joint between an old wall and a newer frame is usually the first place rain gets in.
Cowley is about 2 miles south-west of Hillingdon, in Greater London. We provide window mastic to homeowners, landlords and businesses in Cowley and nearby. Our Greater London coverage runs to 764 places, and Cowley is one of them. There’s also a page for London, about 17 miles away.
Postcode districts we cover here for window mastic: UB8, UB7 and UB10. You will find streets such as Iver Lane, High Road and The Avenue, all of which we cover. We also cover the places around Cowley: Uxbridge (1 mile north), Yiewsley (1 mile south-east), Hillingdon (2 miles north-east), Thorney (2 miles south) and New Denham (2 miles north). Larger places within reach include City of Westminster (14 miles east), Marylebone (14 miles east), Kensington (12 miles east), Hampstead (13 miles east), Ruislip (5 miles north-east) and Brompton (14 miles east).
Landmarks near Cowley
Around Cowley, our work takes us to homes and buildings near The Crown pub, Uxbridge High School and West Middlesex College. The nearest railway station is West Drayton station, about 1.3 miles south of the centre. Other landmarks nearby include British Airways Heritage Collection (0.7 miles north-west) and The Chimes (1.3 miles north). Not far away are Uxbridge Moor and Northala Fields.