Greater London · England
Window & door mastic in Harringay, Greater London
Mastic around window and door frames, sills and patio doors for Harringay, backed by a 12-month guarantee. Call for a quick quote.
- Cracked sealant at the sill ends
- A bead that doesn’t match the frame
- Cracked internal joints between frame and plaster
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.
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.
Window mastic in Harringay
Frames and walls do not 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 mastic that’s falling out in pieces and gaps where the sill meets the wall, we can help, whatever the surface.
Many London homes are flats, with windows high above the street. In a converted house or block, the lease normally says who is responsible for the windows, so it’s worth checking before booking.
You’re covered for a year from the day we finish. If anything is not right with it, call 0345 464 0079 or email us.
- Place
- Harringay (N4, N15, N8)
- Region
- Greater London
- Guarantee
- A year, on every job
- Price
- A clear price before we start
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
When it isn’t the sealant
Some problems need a builder, plumber or other trade rather than us:
- Damp coming through the wall itself rather than the frame joint
- Soft or decayed wood in the frame
- Draughts through the window seals rather than the frame
If you’re not sure, just phone 0345 464 0079 or send us an email and we’ll give you a straight answer before you book.
Surfaces we seal
- Aluminium frames
- Patio & French doors
- uPVC windows
- Composite doors
- Timber windows & doors
- Window sills
Can I do it myself?
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, and the work is guaranteed for a year.
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.
Also near Harringay
More services for Harringay
When to call us in Harringay
Sun, frost and rain wear sealant out. Sunlight dries the surface out, until it loses its stretch and starts to crack.
Most people get in touch after spotting one of these:
- Draughts coming in around windows and doors
- Old mastic that has gone black or come away
- Cracked sealant at the sill ends
- Water coming in at the bottom corners of a door
If you live in an older home near St Paul's Harringay, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Comparing quotes
- When the joint can take water or movement
- How the joint is cleaned and prepared
- Whether VAT is included
- Whether you can choose the colour
Surface by surface
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.
uPVC windows
We clean the frame edge carefully so the plastic isn’t marked, then the new bead is laid against the frame and the wall and tooled smooth.
Frames and glazing around Harringay
Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. With historic houses such as Bruce Castle (about 1.6 miles north-east) nearby, there’s older building stock in the area around Harringay as well as newer homes. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that’s traditional sand mastic.
As a London address, Harringay can be tricky for parking: let us know about parking bays, permits or a driveway. Schools such as South Harringay Infant School are buildings too, and its window and door frames need their mastic kept sound, just like a home’s.
Harringay is about 2 miles north-west of West Hackney, in Greater London. Across the N4 area, our applicators can take on window mastic. Harringay is one of 764 places in Greater London where we work for window mastic. There’s also a page for London, about 6 miles away.
Jobs for window mastic in N4, N15 and N8 is quoted and booked the same way as anywhere else. Whether your property is on Elyne Road, Denton Road and Warham Road or a nearby road, our applicators can take on the job. If you’re just outside Harringay, we cover Duckett's Green (1 mile north), West Green (1 mile north-east), St Ann's (1 mile east), Manor House (1 mile south) and Seven Sisters (1 mile east). We also work in nearby towns such as London (6 miles south), City of Westminster (5 miles south-west), Marylebone (5 miles south-west), Kensington (7 miles south-west), St Pancras (4 miles south) and Shoreditch (4 miles south).
Landmarks near Harringay
In Harringay, that means homes and buildings near Chestnuts Park, Park View School and Moselle Upper School and the streets around them. You’ll also find The Salisbury pub (under half a mile north) and Church of St Andrew (1.1 miles south-east). There’s a railway station in Harringay itself: Harringay Green Lanes station. A little further out are Montfichet's Tower (4.7 miles south) and Markfield Beam Engine and Museum (1.6 miles east). For a walk, there’s Railway Fields and Highgate Hill.
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 the size of the job. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Harringay. A visitor permit or a nearby bay makes the visit run more smoothly.
- We check how each frame can be reached safely.
- All the failed sealant is cut away.
- Frame and wall are cleaned and must be dry before sealing, and primed where the sealant calls for it.
- Deep voids are backed, then the sealant is gunned in.
- The joint is shaped to shed water and the area tidied.
Preparing for the visit
- Mention any tricky access
- Clear items away from the joints we are working on
- Try not to wet indoor joints just before the visit
Get a quote
Call for a quick quote, or send an email if you’d rather. Tell us about the joints that need doing and we will explain what’s involved.
Read more
Why it’s worth doing now in Harringay
Resealing frames is a short job: it takes most of a day for a typical house, less for a few frames. Leave it until water is coming in and you may need plastering and decorating as well. 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.
What it costs depends on the size of the job, how much old material has to come out and access to the work. We give a clear quote before any work starts, so you know where you stand.
Why Harringay clients choose us
- Arbo and Everbuild products
- White, clear, grey or coloured to suit, where the product allows
- Colour agreed with you before work begins
- Over 20 years’ experience
See our cost guide or customer reviews.
Questions from Harringay
I let a flat near Harringay Green Lanes station. Can you help?
Yes, landlords and agents are among the people we work for, and several properties can go on one quote. Just call 0345 464 0079 or send us an email with the address and what needs doing, and we’ll give you a clear price.
Is parking a problem for a job in Harringay?
In much of London, parking needs planning: a visitor permit or a bay close to the door helps a lot.
Do you cover Harringay?
Yes. We cover Harringay and the rest of Greater London, as part of our work across South East England, London and Scotland. For a quote, call 0345 464 0079 or email us.
Which products do you use?
The product depends on the job: sanitary silicone where it gets wet, and sealants suited to movement or weather elsewhere. We use products from Arbo and Everbuild.
How long will my window job take?
The work takes a few hours for a handful of frames, longer for a whole house. Access and how stubborn the old mastic is affect the time most.
Is it messy?
Not at all. We work neatly, protect the area around the joints and tidy up afterwards.
Are you ARBOMaster approved?
Yes. We’re approved under the ARBOMaster scheme, the approved applicator scheme for Arbo sealants.
Do I need to be at home?
That depends on where the joints are. Inside work needs someone to give us access, and for outside work we’ll agree access with you when we book.