Greater London · England
Window Mastic in Northfields
Mastic around window and door frames, sills and patio doors for homes and businesses in Northfields and across Greater London. ARBOMaster approved applicators, fully insured, with a 12-month guarantee.
- Draughty joints inside around the window
- A bead that does not match the frame
- Cracked sealant at the sill ends
Window mastic in Northfields
Most frames have an outside joint and an inside one. Outside, the mastic keeps rain out; the internal joint closes the gap to the plaster and stops draughts. Either or both can be done. We work on uPVC windows, timber windows & doors and composite doors, and the jobs we see most are cracked sealant at the sill ends and a bead that doesn’t match the frame.
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 Northfields as anywhere.
You’re covered for a year from the day we finish. If there’s a problem with it, please ring 0345 464 0079 or send us an email.
- Where
- Northfields (W5, W13, TW8)
- Wider area
- Greater London
- Cover
- One year on every job
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
What affects the quote in Northfields
We quote each job individually. These are the things that affect it:
- The amount of work
- How many rooms, windows or areas are involved
- The type of sealant required
- Any mould that needs treating
What you pay reflects the work, not guesswork. That’s why we ask about the job first and give you a clear price before work begins.
Helping us quote
The more you tell us, the more accurate the quote. When you get in contact, it helps to mention:
- The address or postcode of the job
- Pictures of the joints, sent by email
- Any access issues, like height or stairs
- What’s wrong with the joints now
Asking for a quote is easy: let us know the job and the location, and roughly how big it is. Photos by email help us understand the job, and we will come back to you with a quote.
Should I try it myself first?
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
If you are set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it does not work out, we can still put it right.
Questions from Northfields
Is Northfields in your area for window mastic?
Yes, Northfields is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or drop us an email and let us know what needs doing, and we’ll send you a clear quote.
Is parking an issue for window mastic in Northfields?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly.
Is it worth trying it myself?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Do you work on first-floor windows?
Yes, in most cases. We plan safe access before the job, so mention the height and anything in the way.
Do you work for hotels and businesses?
Yes. We’ve worked for hotels, offices and other businesses.
Can new sealant go over the old?
No. We remove every bit of old sealant first, so the new sealant bonds properly.
What information do you need?
A short description and the location, with photos by email if possible. If we need more, we’ll ask.
Is it messy?
Very little: the area around the joints is protected first, and we tidy up before we go.
When to call us in Northfields
Joint shape matters as much as the product. A skim of sealant over a wide gap soon tears, while a joint packed solid can’t stretch. Backing rod sets the right depth.
Common reasons people contact us include:
- Cracked or shrunken mastic around the frame
- Cold air getting in at the frame edge
- Untidy mastic left by window fitters
- White mastic on grey or black frames
For landlords with property near Brentford station, cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets.
What your quote should include
- Whether all the old sealant comes out first
- How the colour is chosen
- Whether VAT is included
- Who turns up on the day
Nearby places to Northfields
What else we do in Northfields
How the job changes by surface
Timber windows & doors
Older timber windows in stone or brick can suit sand mastic rather than modern sealant. We can talk through the options.
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.
The process
Good joint work is mostly preparation, and we don’t rush it. Every joint is cleaned and dried before new material goes in. In total, it normally takes most of a day for a typical house, less for a few frames. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Northfields. A visitor permit or a nearby bay makes the visit run more smoothly.
- Each frame is looked over and we agree which ones need resealing.
- We remove the old mastic and clean the frame edge and wall.
- Where the gap is deep, backing rod goes in first.
- The new sealant goes on in white, brown, anthracite grey, black or clear to suit.
- Every joint is tooled smooth and checked before we leave.
Before we arrive
- Let us know about earlier repairs to the joints
- Tell us if parking is tricky
- Tell us about any water getting in
Ask for a quote
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is.
Related advice
Windows and doors in Northfields
The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. In London conversions and blocks, the lease decides who is responsible for the frames, so it’s worth checking before booking.
Northfields is in London, so parking needs planning: let us know about parking bays, permits or a driveway. Schools such as Mount Carmel Catholic Primary School are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages.
Northfields is about 1 mile south of Ealing, in Greater London. Jobs in Northfields get the same care as everywhere else we work: old sealant removed completely, careful preparation and a 12-month guarantee. Northfields is one of 764 towns and villages in Greater London we cover. There’s also a page for London, roughly 9 miles from Northfields.
Our applicators cover all of W5, W13 and TW8 for window mastic. If you need window mastic at a property on Burns Road, South Road and Elers Road or anywhere close by, we can help. Northfields is on the A3002, so it’s easy for us to get to with everything needed for window mastic. Nearby, we also carry out window mastic in Brentford (1 mile south-east), Gillette Corner (1 mile south-west), Brentford End (1 mile south), Osterley (2 miles south-west) and Spring Grove (2 miles south-west). Larger places within reach include London (9 miles east), City of Westminster (7 miles east), Marylebone (7 miles east), Kensington (5 miles east), St Pancras (9 miles east) and Shoreditch (10 miles east).
Local landmarks in Northfields
In Northfields, that means homes and buildings near Ealing Fields High School, Great Ealing School and Ealing Park Tavern, among other places. Also close by are Library for Iranian Studies (1.8 miles east) and Lammas Park (less than half a mile north). The closest station to Northfields is Brentford station, about 0.8 miles south of the centre. Other landmarks nearby include Gunnersbury Park House - Large Mansion (1.2 miles east) and Treaty Centre (3 miles south-west). Open spaces near Northfields include Middle Lake and Long Wood.
Honest limits
New sealant cannot fix everything, and we’ll tell you before work begins. Sealant will not put right:
- A frame that has rotted at the joint
- Damp problems in the wall away from the window
- A sash or casement that will not close properly
If in doubt, call 0345 464 0079 or drop us an email and we’ll say what we think before booking.
What we seal
- Composite doors
- Timber windows & doors
- Window sills
- uPVC windows
- Patio & French doors
- Aluminium frames
Landlord and commercial work in Northfields
Whether it’s one flat or a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a one-year guarantee.
We also work for property managers and facilities teams. Several sites can be quoted together, and we’re fully insured for the work.