Greater London · England
Window & door mastic in Merton Park, Greater London
Window mastic across Merton Park and nearby, with every bit of old sealant taken out first and a one-year guarantee.
- Whistling draughts around closed windows
- Hard, cracked sealant around windows
- Water coming in at the bottom corners of a door
Window mastic in Merton Park
Behind a thin line of old mastic there’s sometimes a deep void. Packing it solid with sealant gives a joint that can’t flex, so deep gaps get backing rod first. The sealant then grips the two sides it should. We work on composite doors, patio & French doors and uPVC windows, and the jobs we see most are leaking joints at the ends of sills and white mastic on grey or black frames.
London homes have every kind of window, from timber sashes in period terraces to aluminium and uPVC in newer blocks. The mastic around them dries out and cracks with age, letting in draughts and water.
You are covered for a year from the day we finish. If there’s a problem with it, please call 0345 464 0079 or email us.
- Place
- Merton Park (SW19, SW20, SM4)
- Region
- Greater London
- Guarantee
- One year on every job
- Quote
- A clear quote up front
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Landlord and commercial work in Merton Park
Businesses can book us for washrooms, kitchens, offices and more. For commercial premises, we can talk through working times when we quote.
From a single let to a portfolio, you get the same standard of work: the old material taken out, careful preparation and a 12-month guarantee.
How we quote for window mastic
You will get a clear quote before any work starts. It’s based on:
- Whether the work is at height
- The old material and how stubborn it is
- The amount of work
- Any working-time requirements on site
What it costs depends on the size of the job, how much old material has to come out and how easy the joints are to reach. We give a clear quote before any work starts, so you know where you stand.
What to tell us for a quote
To help us quote quickly, let us know:
- The type of property
- How we’d reach the joints
- Roughly how big the job is
- If someone has resealed it before
To get a quote, phone 0345 464 0079 or send us an email with the location and a short description of the problem. You will have a clear quote before work begins.
What happens on the day
On the day, there’s very little for you to do. Point us to the joints and we’ll get on with it. The work itself takes a few hours for a handful of frames, longer for a whole house from start to finish. For a job in Merton Park, 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.
- Where gaps are deep, backing rod goes in first.
- A flexible, weatherproof sealant is applied in a colour to suit the frame.
- We clear up and check every joint is fully closed.
Getting ready for the visit
- Tell us about any water getting in
- Mention if the joints have been sealed before
- Clear items away from the joints we are working on
How to get a quote
We do not publish a price list, as no two jobs are quite the same. Instead, your job gets its own clear quote. To get started, call 0345 464 0079 or drop us an email.
Related advice
What window mastic looks like in Merton Park
Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. With historic houses such as Southside House (about 1.4 miles west) nearby, there’s older building stock in the area around Merton Park as well as newer homes. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic.
If you look after a building such as Merton Park Primary School, the mastic around its windows and doors needs looking after like any other building’s. In the older streets around St Mary's Church, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Merton Park is about 1 mile south-east of Wimbledon, in Greater London. Every kind of property in Merton Park is covered for window mastic, old or new, large or small. The work is guaranteed for a year. We cover 764 towns and villages across Greater London, from the larger towns to small villages. We also work in London, about 8 miles from Merton Park.
Every address in SW19, SW20 and SM4 is within our area for window mastic. Local streets include Mina Road, Manor Road and Cecil Road, all of which we cover. We also cover the places around Merton Park: Wimbledon Chase (1 mile west), Bushey Mead (1 mile west), Cannon Hill (1 mile south-west), Wimbledon (1 mile north-west) and Crooked Billet (1 mile north-west). Further out, we also cover London (8 miles north-east), City of Westminster (7 miles north), Marylebone (8 miles north), Kensington (6 miles north), St Pancras (9 miles north-east) and Shoreditch (10 miles north-east).
Around Merton Park
We work in homes and buildings around Wibbas Down Inn, Morden Hall Park and Wimbledon School of Art. For rail, the closest station is South Merton station, roughly 0.5 miles south of the centre. Nearby you will also find St George's Hospital (1.6 miles north-east) and Southside Wandsworth (3.1 miles north). Not far away are Merton Park Green Walks and Henman Hill.
Should I try it myself first?
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
Sealing over old silicone is the commonest DIY error. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
Common problems we fix in Merton Park
Every frame moves through the day. A plastic or aluminium frame lengthens in sunshine and shortens as it cools, while the masonry beside it stays put. A sealant that can’t keep up eventually tears.
Most people get in touch when they notice something like this:
- Cracked internal joints between frame and plaster
- Draughts coming in around windows and doors
- White mastic on grey or black frames
- Water coming in at the bottom corners of a door
For landlords with property near South Merton station, sound mastic around windows and doors keeps out the draughts and damp that tenants notice first.
Comparing quotes
- How long to leave it before use
- How hidden problems are handled
- Which colour the sealant will be
- Who does the work, and how experienced they are
Leave it or put it right?
Resealing frames is a short job: it takes anything from an hour or two to a full day, depending on how many frames there are. Wait for damp to appear and there may be plaster and decorating to sort out too. In London conversions, one flat’s bathroom is often above another flat’s ceiling, 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 Merton Park.
The cost reflects the work involved, not a rough estimate. That is why we ask about the job first and send you a clear quote before any work starts.
Why Merton Park customers choose us
- Approved under the ARBOMaster scheme
- Anti-fungal silicone where joints get wet
- Every job guaranteed for a year
- A choice of colours where the product allows
Merton Park: your questions answered
Is parking an issue for window mastic in Merton Park?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
Do you cover Merton Park for window mastic?
Yes. Our work covers London and the South East, and Merton Park is part of that. You can phone 0345 464 0079 or drop us an email and tell us what needs doing.
Will you leave a mess?
Not at all. The area is protected while we work and cleaned up afterwards.
Do I have to be there?
We need access to the joints, so we will agree that with you when we book. Indoors, that generally means someone at home.
How long will my window job take?
That depends on the number of frames, how they’re reached and the state of the old mastic. You’ll know the timing when we quote.
Can you do the inside joint as well?
Yes. The outside joint keeps the weather out, and the inside joint stops draughts and finishes the reveal. We can do either or both.
Do you remove the old sealant?
Yes. Sealing over old sealant is the main reason resealing fails early, and it’s something we never do.
I’m a tenant. Can you help?
Of course. Check with your landlord; we can send the quote to them too.
Nearby places to Merton Park
Other services in Merton Park
When something else is needed
Sealant is not the answer to every problem, and we will tell you before work begins. It will not solve:
- A failed sealed unit that has misted up
- A frame that has rotted at the joint
- Faulty window hardware
If in doubt, phone 0345 464 0079 or send us an email and we will say what we think before you book.
Where we work in Merton Park
- uPVC windows
- Timber windows & doors
- Patio & French doors
- Composite doors
- Aluminium frames
- Window sills