Greater London · England
Window & door mastic in Church End, Greater London
We cover Church End for mastic around window and door frames, sills and patio doors. Old material cut out, joints cleaned and sealed neatly and every job guaranteed for a year.
- Sealant in the wrong colour for the frame
- Draughts coming in around windows and doors
- Cracked internal joints between frame and plaster
About our window mastic in Church End
Behind a thin line of old mastic there’s sometimes a deep void. Packing it solid with sealant gives a joint that cannot flex, so we fit backing rod to set the right depth. That way the new bead bonds to the frame and the wall only. We work on aluminium frames, composite doors and patio & French doors, and common reasons people get in touch are gaps left after new windows were fitted and old mastic that has gone black or come away.
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, in Church End as anywhere.
A 12-month guarantee comes with the work, just as it does everywhere we cover.
- Place
- Church End (NW10, NW2)
- Wider area
- Greater London
- Cover
- One year on every job
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
How the job changes by surface
Timber windows & doors
Soft or rotten wood cannot be sealed successfully. If we find rot, we’ll tell you before going ahead, as that’s a job for a joiner.
Window sills
Sills catch the water running down the glass, so the sill ends and the joint under the frame are vital. They’re cut out and resealed with exterior sealant.
What happens if it’s left?
Choosing the product is half the job. Decorators’ caulk and bathroom silicone aren’t designed for outside joints that move. A low-modulus exterior sealant keeps its stretch through hot and cold weather. 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 Church End.
Doing several joints on one visit is normally more efficient than separate visits, so it’s worth mentioning everything you’d like done. You’ll get one clear quote for the whole job.
Why Church End customers choose us
- Rated 4.9 stars on Google
- A sealant colour to suit the surroundings
- A 12-month guarantee on all work
- Quality sealants from Arbo and Everbuild
Read what affects the cost and what customers say.
Also near Church End
More services for Church End
Questions from Church End
Can you help a landlord with a rental near Harlesden station?
Yes. We work for landlords and agents as well as householders, and several properties can go on one quote. Just phone 0345 464 0079 or email us with the address and what needs doing, and we’ll give you a clear price.
Can parking be tricky for a visit in Church End?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
Can new sealant go over the old?
No. New silicone will not bond to old silicone, and anything trapped underneath, including mould and water, stays there. We remove it all first.
What does window mastic cost?
There’s no set price, as it depends on the job: its size, the old material, access and the product needed. We agree the price before any work begins.
Can you quote for more than one area?
Yes. Tell us about everything you’d like done and we will quote it together.
Will resealing my frames help with draughts?
If the draught is coming in around the frame, yes. If it’s coming through the window seals, we will tell you.
Do I need to be at home?
For indoor joints, yes, someone needs to let us in. After that, you can carry on with your day.
Does the work come with a guarantee?
Yes. Each job is covered for 12 months, inside or out.
Signs you need window mastic in Church End
Mastic ages in the weather. Sunlight dries the surface out, and over the years it loses its give, cracks and comes away.
The problems people normally mention when they call are:
- Mastic that has split away from the wall
- Gaps left after new windows were fitted
- Rain getting in at the frame or under the sill
- Cracked sealant at the sill ends
If you look after a building such as St Mary's CofE Primary School, its window and door frames need their mastic kept sound, just like a home’s.
Questions to ask before booking
- Are they insured?
- How the colour is chosen
- What guarantee comes with the work
- What happens if the job turns out different
Windows and doors in Church End
Historic houses like Fenton House (about 3.2 miles east) are a reminder that the area around Church End has older buildings as well as new. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window. London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
As a London address, Church End can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. Homes close to Church of St Mary include some older properties, and the joint between an old wall and a newer frame is generally the first place rain gets in.
Church End is about 3 miles west of Hampstead, in Greater London. We provide window mastic to homeowners, landlords and businesses in Church End and nearby. 764 places in Greater London are on our list, large and small. For nearby work, see our London page, about 7 miles away.
Postcode districts we cover here for window mastic: NW10 and NW2. Whether your property is on Fry Road, Park Road and High Road or a nearby road, we can help. We also cover the places around Church End: Brent Park (1 mile north-west), Stonebridge (1 mile south-west), Neasden (1 mile north), Harlesden (1 mile south) and Willesden (1 mile east). Larger places within reach include London (7 miles south-east), City of Westminster (5 miles south-east), Marylebone (5 miles south-east), Kensington (4 miles south-east), St Pancras (6 miles east) and Shoreditch (8 miles east).
Local landmarks in Church End
We work in homes and buildings around Stonebridge Park Public House, The Swaminarayan School and St Claudine's Catholic School for Girls, among other places. For rail, the closest station is Harlesden station, roughly 0.7 miles south-west. Well-known places in the area include Neasden Hospital (0.5 miles north-west) and Brent Museum and Archives (1 mile east). The countryside around Church End includes The Long Water and Castlebar Hill.
When it is not the sealant
We won’t take on work that won’t last, so these are the limits:
- Draughts through the window seals rather than the frame
- Condensation trapped between the panes
- Soft or decayed wood in the frame
Not sure which it is? You can ring 0345 464 0079 or drop us an email and we will tell you honestly.
Surfaces we seal
- Patio & French doors
- Composite doors
- Timber windows & doors
- uPVC windows
- Window sills
- Aluminium frames
DIY sealant or a professional job?
If you’ve already had a go yourself, that is fine. We cut it out and start again, so tell us about it when you ask for a quote.
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it fails, we can still redo it.
The process
Our applicators work methodically: protection first, then preparation, sealing and a tidy-up. For most jobs that takes a morning for a couple of windows and a door. In a London area like Church End, the main things to plan are parking and access: let us know about parking, the floor we will be working on and any lift or shared entrance.
- First, we go round the frames with you and agree the list.
- The old mastic is cut out and scraped back to clean surfaces.
- Deep gaps get closed-cell backing rod to set the depth.
- 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
- For indoor joints, keep the area dry beforehand if you can
- Let us know if you’ve seen damp or leaks
- Tell us about any previous sealing or DIY attempts
How to get a quote
For a quote, call 0345 464 0079 or drop us an email with the location and a short description of the problem. We’ll send you a clear quote before any work starts.
Advice
For landlords and businesses
Housing providers, facilities teams and property managers book us too. We can quote a run of properties together, and we’re fully insured.
Hotels need rooms back in use, so the work can be planned room by room. We’ve worked in hotels as well as homes and businesses.