Greater London · England
Finsbury Window Mastic
Mastic around window and door frames, sills and patio doors for homeowners, landlords and businesses in Finsbury. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Cracked internal joints between frame and plaster
- A bead that doesn’t match the frame
- Whistling draughts around closed windows
How we quote for window mastic
Your quote is based on your job. We take into account:
- The number of rooms or windows
- Which sealant suits the joint
- Any mould that needs treating
- The old material and how stubborn it is
What it costs depends on the size of the job, how hard the old material is to remove and access to the work. We give a clear quote before work begins, so you know where you stand.
What we need to know
Before you ask for a quote, have a think about:
- The address or postcode of the job
- Access, such as stairs, a lift or height
- Roughly how big the job is
- Any previous sealing or DIY work
If you are in Finsbury and need window mastic, call 0345 464 0079 or drop us an email. A short description of the job and where it is helps us quote, and you will get a clear quote before work begins.
Window mastic in Finsbury
Most frames have an outside joint and an inside one. Outside, the mastic keeps rain out; inside, the joint between frame and plaster stops draughts and tidies the reveal. Either or both can be done. If you have whistling draughts around closed windows and damp patches on the reveal after heavy rain, we can help, whatever the surface.
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 Finsbury as anywhere.
All of our work is guaranteed for twelve months.
- Location
- Finsbury (EC1V, N1, EC2A)
- Wider area
- Greater London
- Cover
- A year, on every job
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
FAQs for Finsbury
Can you help a landlord with a rental near Old Street station?
Yes. We work for landlords and letting agents as well as householders, and several properties can be quoted together. You can ring 0345 464 0079 or drop us an email with the details for a clear quote.
Do you cover Finsbury for window mastic?
Yes, Finsbury is within the area we cover. Our work covers London and the South East. Just ring 0345 464 0079 or send us an email with a few details of the job, and we’ll give you a clear quote.
What information do you need?
Tell us what needs doing and where. We’ll ask anything else we need to know.
Can I add another job to the visit?
Yes, we can. More than one area can be quoted together.
What sealant do you use?
Products from Arbo and Everbuild, among others, chosen to suit the joint. We explain the product when we quote.
Can you do upstairs windows?
Yes, where it’s safe. Higher or awkward frames may need extra access, and we will confirm what’s needed.
Do you take out the old sealant first?
Yes, every time. New sealant won’t bond properly to old, so the joint is cleaned back first.
How long should I leave it?
That depends on the sealant used, so follow the cure time we give you.
How to look after the new joints
After the cure time, these simple habits help:
- Make sure the drainage slots aren’t blocked
- Do not aim a pressure washer at the joints
- Repaint timber before it’s bare
- Clean frames with a soft cloth and soapy water
Wipe the frames with soapy water when you clean the windows, and avoid solvent cleaners on the sealant.
Draughts get worse, not better. As old mastic keeps shrinking, the gap widens, and a cold room gets colder. Resealing closes it.
Landlords, agents and businesses in Finsbury
Whether it’s one flat or a portfolio, you get the same standard of work: the old material taken out, careful preparation and a 12-month guarantee.
We work for landlords and agents as well as homeowners. Resealing between tenancies keeps a property looking cared for before the next move-in.
What the job involves on each surface
Aluminium frames
Large aluminium doors have long joints down each side and across the head, and the bottom joint sees the most water. Each is cleaned, backed where deep and resealed.
uPVC windows
uPVC expands and contracts noticeably with temperature, so we use a flexible, low-modulus sealant. White is the usual colour, with brown, anthracite grey and black for coloured frames.
Window mastic in Finsbury: local notes
In London conversions and blocks, the lease decides who is responsible for the frames, so check that before booking. London and the South East are among the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Rented homes near Old Street station change hands often, and cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets. As a London address, Finsbury can be tricky for parking: let us know about parking bays, permits or a driveway.
Finsbury is about 2 miles north of London, in Greater London. If you need window mastic in Finsbury, it’s easy to get a quote: please phone 0345 464 0079 or send us an email. We’re based in Crawley and cover Greater London. Our Greater London coverage runs to 764 places, Finsbury among them.
Here we cover the EC1V, N1 and EC2A postcode area for window mastic. Whether your property is on Oat Lane, Long Lane and Love Lane or anywhere close by, our applicators can take on the job. Finsbury is on the A1 and A501, so it’s easy for us to get to with everything needed for window mastic. Nearby, we also carry out window mastic in St Luke's (1 mile north), Barbican Estate (1 mile south), City of London (1 mile south), Bishopsgate (1 mile south-east) and Shoreditch (1 mile east). We also work in nearby towns such as City of Westminster (3 miles west), Kensington (5 miles west), Walthamstow (5 miles north-east), Hampstead (4 miles north-west), Ruislip (14 miles west) and Brompton (4 miles south-west).
What’s near Finsbury
Around Finsbury, our work takes us to homes and buildings near Artillery Ground, Barts Health Archives and Charterhouse Square School, among other places. Other local landmarks include The Jugged Hare pub (within half a mile south), St Mary-at-Hill (0.9 miles south-east) and Central Foundation Boys' School (within half a mile north-east). Finsbury has its own railway station: Old Street station. Other landmarks nearby include Honourable Artillery Company Museum (less than half a mile east) and Gabriel's Wharf (1.2 miles south-west). Green spaces nearby include Barnsbury Wood and Ludgate Hill.
Nearby places to Finsbury
Other services in Finsbury
Do you need window mastic in Finsbury?
Some failures date back to when the windows were fitted. Mastic laid onto dusty, damp or crumbling surfaces never bonded as it should, so it comes away long before its time.
It’s worth asking for a quote if you see:
- Old mastic that has gone black or come away
- A bead that does not match the frame
- Cracked internal joints between frame and plaster
- Gaps where the sill meets the wall
Managing a site like Prior Weston Primary School and Children's Centre? Then larger buildings have plenty of frames, and the mastic around each one ages.
Questions to ask before booking
- What product goes in the joint
- Who turns up on the day
- Is the old sealant removed completely?
- The length of the guarantee
How the visit works
Most of a good job is in the preparation, and we do not rush it. Joints are cleaned back and dried before anything new goes in. In total, it usually takes most of a day for a typical house, less for a few frames. In Finsbury, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- Each frame is looked over and we agree which ones need resealing.
- The old mastic is cut out and scraped back to clean surfaces.
- 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.
- We tool each bead neatly and check every joint is closed.
How to prepare
- On commercial sites, let us know about site rules
- Tell us about access, such as stairs, a lift or high-level joints
- Move anything stored near the joints
Getting a quote
Every job is quoted individually, so start by telling us what you need. Just call 0345 464 0079 or email us with the details, and pictures are welcome.
Read more
Why it’s worth doing now in Finsbury
Redecorating is a good moment to renew the mastic. Fresh joints finish the job neatly, and it’s easier while the walls are being worked on anyway. 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. Dealing with it early is far simpler.
Homes and businesses are quoted the same way: how much there is to do, how we reach it and what it needs, plus any working-time requirements on site. Ask us for a quote and we’ll explain what it covers.
Why book with us
- One-year guarantee on every job
- Domestic, commercial and hotel work
- Over 20 years’ experience
- Arbo and Everbuild products
See what affects the cost and our reviews.