Greater London · England
Window Mastic in North Wembley
Mastic around window and door frames, sills and patio doors for North Wembley, backed by a one-year guarantee. Ask us for a quote.
- Gaps where the sill meets the wall
- Untidy mastic left by window fitters
- Black, perished sealant on frames
How we handle window mastic in North Wembley
Frames and walls don’t move together. Plastic and aluminium frames move with the temperature, while masonry stays fairly still. So the sealant has to stretch and recover, which is why we use a low-modulus product. If you have cracked sealant at the sill ends and a bead that doesn’t match the frame, we can help, on composite doors, window sills 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. 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 12-month guarantee, wherever you are in Greater London.
- Where
- North Wembley (HA0, HA9, UB6)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before work begins
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Frames and glazing around North Wembley
In London conversions and blocks, the lease decides who is responsible for the frames, so check that before booking. Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
As a London address, North Wembley can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. Homes close to Church of St John include some older properties, and frames set in older brick or stone need a sealant that suits the wall as well as the frame.
North Wembley is about 2 miles south-east of Harrow, in Greater London. Whether you are in the middle of North Wembley or further out, window mastic is available for homes and businesses alike, from flats and houses to offices and hotels. North Wembley is one of 764 places in Greater London where we work for window mastic. For nearby work, see our London page, about 10 miles away.
Work in HA0, HA9 and UB6 works the same way as everywhere else we cover. You will find streets such as Elm Road, East Lane and High Road, all of which we cover. Being close to the A4089, North Wembley is easy for our applicators to reach. We also cover Brondesbury Park (1 mile north), Sudbury Hill (1 mile west), Sudbury (1 mile west), South Kenton (1 mile north) and Perivale (1 mile south-west). We also work in nearby towns such as London (10 miles south-east), City of Westminster (7 miles south-east), Marylebone (7 miles east), Kensington (6 miles south-east), St Pancras (8 miles east) and Shoreditch (10 miles east).
Local landmarks in North Wembley
Locally, jobs take us to homes and businesses close to Wembley High Technology College, Preston Park and J.J. Moon's pub and the streets around them. North Wembley has its own railway station: Wembley Central station. Other landmarks nearby include Clementine Churchill Hospital (1.4 miles north-west) and London Designer Outlet (0.8 miles east). The countryside around North Wembley includes Perivale Wood and Castlebar Hill.
Also near North Wembley
Also in North Wembley
Work for landlords, hotels and businesses
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
If you manage several properties in or around North Wembley, several properties can be quoted together. Send us the addresses and the work at each.
Should I try it myself first?
A DIY attempt doesn’t rule out a professional job. We remove it and do the joint properly.
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and doesn’t move well, and getting the depth right matters as much as the look.
The process
Most of a good job is in the preparation, and we don’t rush it. Every joint is cleaned and dried before new material goes in. All told, the work takes a morning for a couple of windows and a door. In a London area like North Wembley, the main things to plan are parking and access: tell us about permits, visitor bays or off-street space, which floor we are working on and whether there’s a lift.
- 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.
- 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 tricky access
- For indoor joints, keep the area dry beforehand if you can
- Tell us if parking is tricky
How to get a quote
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is. Whenever you’re ready, call 0345 464 0079 or email us.
Advice
What affects the quote in North Wembley
Jobs vary more than people expect. What affects the quote:
- Whether old sealant or filler has to be cut out
- Mould in or behind the old joints
- How much there is to do
- The type of sealant required
Instead of a standard rate, we look at what your job involves: how many joints, what’s in them now and how we reach them. The price is agreed before we begin.
Asking for a quote
There’s no need for technical detail. It helps if you can tell us:
- The type of property
- What the problem is, such as mould, gaps, leaks or cracking
- Any access issues, like height or stairs
- Where the property is
Want a quote for window mastic? Please call 0345 464 0079 or drop us an email and tell us about the job. We will explain what we’d do and send you a clear quote before we start.
Why it’s worth doing now in North Wembley
The work is quick compared with the damage it prevents: the visit takes most of a day for a typical house, less for a few frames. Wait for damp to appear and there may be plaster and decorating to sort out too. In a London flat, a failed joint rarely stays your problem alone: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
No two jobs are quite the same, so we quote each one individually. The number of joints, how easy they are to reach and the sealant needed all play a part.
Why choose Mr Mastic in North Wembley
- Tidy, careful work
- Over 20 years’ experience
- Colour agreed with you before work begins
- Arbo and Everbuild products
Read what affects the cost or customer reviews.
When it is not the sealant
We won’t take on work that will not last, so here’s what sealant can’t put right:
- Rotten timber, which needs a joiner first
- Draughts through the window seals rather than the frame
- Damp coming through the wall itself rather than the frame joint
If you are not sure, just phone 0345 464 0079 or send us an email and we’ll give you a straight answer.
Where we work in North Wembley
- uPVC windows
- Patio & French doors
- Timber windows & doors
- Composite doors
- Window sills
- Aluminium frames
Do you need window mastic in North Wembley?
Some failures date back to when the windows were fitted. Mastic laid onto dusty, damp or crumbling surfaces didn’t grip properly, so it comes away long before its time.
Look out for these signs:
- Mastic that has split away from the wall
- Rushed sealant from a window installation
- Whistling draughts around closed windows
- Leaking joints at the ends of sills
Letting a property close to Wembley Central station? Then sound mastic around windows and doors keeps out the draughts and damp that tenants notice first.
Questions to ask before you book
- When the joint can take water or movement
- Which sealant they’ll use, and why
- The length of the guarantee
- Is the old sealant removed completely?
Your questions about window mastic in North Wembley
Can you do window mastic in North Wembley?
Yes. We work across London and the South East, and North Wembley is part of that. Just call 0345 464 0079 or drop us an email with a few details of the job.
Is parking a problem for a job in North Wembley?
Parking in North Wembley, as in most of London, takes a little planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
Can you get sealant to suit coloured frames?
Yes. White, brown, anthracite grey, black and clear sealants are all available.
Should I try DIY first?
Some simple jobs can be done by a careful DIYer. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
What information do you need?
A short description and the location, with pictures by email if possible. We’ll ask anything else we need to know.
Can you seal over the old sealant?
No. We remove every bit of old sealant first, so the new joint bonds to clean surfaces.
Do you work on first-floor 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.
Are you an approved applicator?
Yes. We are approved under the ARBOMaster scheme, the approved applicator scheme for Arbo sealants.