Greater London · England
Window Mastic in Islington
Window mastic for Islington and the surrounding area: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Cracked or shrunken mastic around the frame
- A bead that does not match the frame
- Cold air getting in at the frame edge
Window mastic in Islington, done properly
The new joint doesn’t have to be white. We can seal in white, brown, anthracite grey, black or clear, so the bead blends with the window rather than framing it. If you are dealing with mastic that’s falling out in pieces and cold air getting in at the frame edge, we can help, on patio & French doors, window sills and composite doors alike.
Much of London’s older housing was built with timber sash windows, some still in place and some long since replaced. Either way, the mastic between frame and brickwork is what stops draughts and rain getting in, in Islington as anywhere.
A one-year guarantee comes as standard, so you’re not left on your own once the job is done.
- Where
- Islington (N1, N7, NW1, EC1V)
- Wider area
- Greater London
- Guarantee
- A year, on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
What affects the cost of window mastic
Jobs vary more than people expect. What affects the quote:
- How much old sealant there is and how hard it is to remove
- When we can work, for business premises
- The size of the job
- Any mould that needs treating
The cost depends on the amount of work, how much old material has to come out and how easy the joints are to reach. You will have a clear quote before any work starts, so you know where you stand.
What to tell us for a quote
Before you ask for a quote, have a think about:
- Access, such as stairs, a lift or height
- A few pictures by email, if you can
- Roughly how big the job is
- What the problem is, such as mould, gaps, leaks or cracking
We do not publish a price list. Instead, your job gets its own clear quote. To get started, phone 0345 464 0079 or email us.
Your questions about window mastic in Islington
Can you help a landlord with a rental near Essex Road station?
Yes. We work for landlords and letting agents as well as homeowners, and several properties can be quoted together. You can call 0345 464 0079 or email us with the details for a clear quote.
Can you do window mastic in Islington?
Yes, Islington is within the area we cover. We work across London and the South East. Just ring 0345 464 0079 or email us with a few details of the job, and we will give you a clear price.
Where is Mr Mastic based?
Mr Mastic is based in Crawley. Our applicators cover Islington.
Does the work come with a guarantee?
Yes. Our 12-month guarantee covers every job.
Can you match the sealant to my frames?
Yes, in most cases. Tell us the frame colour when you get in touch and we will match it as closely as we can.
How long does it take to reseal the windows on a house?
A handful of frames is a short visit. We confirm the timing with your quote.
How long should I leave it?
Most sealants are touch-dry well before they’re fully cured. We’ll tell you how long to leave the joint.
Do you work for hotels and businesses?
Yes. Commercial and hotel work is a large part of what we do. We can talk about working times when we quote.
How the visit works
We keep the work tidy and contained to the joints we are treating, so you can carry on as normal. The job normally takes a few hours for a handful of frames, longer for a whole house, and we explain the cure time before we leave. For a job in Islington, parking and access are the things to plan: tell us about permits, visitor bays or off-street space, which floor we’re working on and whether there’s a lift.
- We check each frame and agree which ones need doing.
- The old mastic is cut out and the surfaces cleaned back.
- We fit backing rod in deep gaps so the sealant is the right depth.
- New exterior sealant goes on in a matching colour and is tooled smooth.
- Every joint is checked before we leave.
How to prepare
- Move anything stored near the joints
- Try not to wet indoor joints just before the visit
- For business premises, tell us about site rules or sign-in
Ask for a quote
For a quick quote, get us on the phone, or send an email if you’d rather. Describe what needs sealing and we’ll explain what’s involved.
Read more
How to look after the new joints
Good habits help new joints last longer. A few tips:
- Air rooms to keep condensation down around windows
- Clear any debris from frame drain holes
- Avoid blasting the frames with a pressure washer
- Keep paint off silicone joints
Most silicone sealants will not take paint, so mention any painting plans before any work starts. We can use a paintable sealant where that matters.
Look out for the warning signs: cracks in the mastic, gaps you can see light through, damp on the reveal or mould around the inside of the frame. If you notice one, it’s time to get the joint looked at.
What window mastic looks like in Islington
The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. In a converted house or block, who looks after the windows depends on the lease, so it’s worth checking before booking.
Rented homes near Essex Road station change hands often, and sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. Islington is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. For site and facilities teams at buildings such as Islington Proprietary School, its window and door frames need their mastic kept sound, just like a home’s.
Islington is about 3 miles north-east of City of Westminster, in Greater London. Our applicators cover window mastic for homeowners, landlords and businesses in Islington and the surrounding area. Our Greater London coverage runs to 764 places, Islington among them.
Every address in N1, N7, NW1 and EC1V is within our area for window mastic, from the main roads to the quietest streets. Streets in the area include Gibson Square, Old Royal Free Square and Cloudesley Square, all of which we cover. Main roads around Islington include the B515 and A5203. We also cover the places around Islington: Pentonville (1 mile south), Angel (1 mile south), Barnsbury (1 mile north-west), Clerkenwell (1 mile south) and Lower Holloway (1 mile north-west). We also work in nearby towns such as London (3 miles south), City of Westminster (3 miles south-west), Kensington (5 miles south-west), Walthamstow (5 miles north-east), Hampstead (3 miles west) and Ruislip (13 miles west).
Near you in Islington
We work in homes and buildings around Islington Green School, The King's Head Public House and Pilsudski Institute of London. Other local landmarks include Barnard Park (within half a mile south-west) and St Mary's CofE Primary School (less than half a mile east). There’s a railway station in Islington itself: Essex Road station. Other landmarks nearby include King's College Hospital Charity (0.7 miles north-west) and Montfichet's Tower (1.7 miles south). For a walk, there’s Barnsbury Wood and Ludgate Hill.
When something else is needed
We won’t take on work that will not last, so here’s what sealant can’t put right:
- Faulty window hardware
- Soft or decayed wood in the frame
- A failed sealed unit that has misted up
Not sure which it is? You can phone 0345 464 0079 or email us and we will tell you honestly.
What we seal
- Window sills
- Aluminium frames
- Timber windows & doors
- Patio & French doors
- Composite doors
- uPVC windows
Nearby places to Islington
What else we do in Islington
Different surfaces, different methods
Timber windows & doors
Soft or rotten wood cannot be sealed successfully. We’ll point out any rot we find, as a joiner will need to deal with it.
Window sills
Every drop off the glass ends up on the sill, so the sill ends and the joint under the frame are vital. Each is cleaned out and resealed.
Can I do it myself?
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.
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.
Why deal with it now?
If you are painting or rendering, reseal at the same time. A clean new bead makes new paint or render look finished, and it’s easier while the walls are being worked on anyway. Damp from a failed joint spreads quietly in older London brickwork and timber, and by the time it shows on a wall or ceiling in Islington, the repair is bigger than the sealant job would have been.
Rather than a set price list, we price the job in front of us: the amount of work, the old material and the access. You will know the price before we begin.
What you get with us
- White, clear, grey or coloured to suit, where the product allows
- Old sealant always removed completely
- Domestic, commercial and hotel work
- Trusted Arbo and Everbuild sealants
Take a look at what affects the cost or customer reviews.