Greater London · England
Window & door mastic in Merton, Greater London
Window mastic for Merton and the surrounding area: careful preparation, the right product and tidy work. Call for a quick quote.
- Hard, cracked sealant around windows
- Cold air getting in at the frame edge
- Leaking joints at the ends of sills
What the job involves on each surface
Patio & French doors
Water at the foot of a door frame is not always the mastic: worn seals, blocked drainage slots or a poor threshold detail can be the cause. We check before we reseal.
uPVC windows
Fitters’ mastic on plastic frames is sometimes thin and rushed. We cut it out, back any deep gaps and reseal properly.
About our window mastic in Merton
A cold draught around a closed window often comes from the frame edge. Resealing that joint can make a room feel noticeably less draughty. If the draught is through the window seals instead, we’ll tell you. We’re often asked to deal with cracked or shrunken mastic around the frame and gaps left after new windows were fitted, on timber windows & doors, patio & French doors and uPVC windows.
From mansion-block windows to modern glazing in new flats, London has every kind of frame. The mastic around them dries out and cracks with age, letting in draughts and water.
You get a one-year guarantee, the same in Merton as everywhere else we work.
- Location
- Merton (SW19)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Price
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
What affects the quote in Merton
You will get a clear quote before work begins. It takes into account:
- Which sealant suits the joint
- Mould in or behind the old joints
- Any working-time requirements on site
- How many areas need sealing
Commercial jobs are quoted on the same basis as homes: the amount of work, the access and the products needed. Call for a quick quote and we will explain what it covers.
Asking for a quote
What to tell us when you ask for a quote:
- Whether it has been sealed before
- If it’s domestic, commercial or a hotel
- Access, such as stairs, a lift or height
- Pictures of the joints, sent by email
We don’t publish a price list, because every job is different. Instead, we give you a clear price for your job. To arrange one, call 0345 464 0079 or drop us an email.
Questions from Merton
Can you help a landlord with a rental near Haydons Road station?
Yes, landlords and agents are among the people we work for. Just call 0345 464 0079 or email us with the address and what needs doing, and we’ll send you a clear quote.
Is Merton in your area for window mastic?
Yes, Merton is within the area we cover. We work across London and the South East. Just phone 0345 464 0079 or email us with a few details of the job, and we’ll give you a clear quote.
Can you match the sealant to my frames?
Yes. We can use white, brown, anthracite grey, black or clear.
Which products do you use?
Each joint gets the product that suits it. Where it moves, gets wet or faces the weather makes a difference, and we will explain our choice.
Do you have insurance?
Yes. We’re fully insured, and we have been doing sealant work for more than 20 years.
Will the old sealant be removed?
Yes. We cut out all the old sealant and clean the joint.
Do you do commercial work?
Yes. We work in offices, washrooms, hotels and other commercial premises, as well as homes. Working times can be discussed when we quote.
When is the sealant fully cured?
Many sealants skin over quickly but take longer to cure fully. We’ll give you the cure time for the product we used.
Nearby places to Merton
Also in Merton
Do you need window mastic in Merton?
A lot of older mastic was never designed to stay flexible. Once it has hardened, the frame’s movement tears it from the wall, and a gap opens along one edge.
Look out for any of the following:
- Cracked internal joints between frame and plaster
- Water coming in at the bottom corners of a door
- Sealant in the wrong colour for the frame
- Gaps left after new windows were fitted
For landlords with property near Haydons Road station, renewing tired window mastic between tenants heads off draught and damp complaints.
Comparing quotes
- Which colour the sealant will be
- The length of the guarantee
- What preparation is included
- What the quote includes, VAT included or not
Why it’s worth doing now in Merton
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. In a London flat, a failed joint rarely stays your problem alone: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
Doing several joints on one visit generally makes better use of the time than several visits. You will get one clear quote for the whole job.
What you get with us
- Sanitary silicone with an anti-fungal additive in wet areas
- We leave the area clean and tidy
- Sealant colour chosen to suit
- White, clear, grey or coloured to suit, where the product allows
Take a look at how sealant jobs are priced or what customers say.
Windows and doors in Merton
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. In a converted house or block, who looks after the windows depends on the lease, so check that before booking.
As a London address, Merton can be tricky for parking: let us know about parking bays, permits or a driveway. For site and facilities teams at buildings such as Merton Abbey Primary School, larger buildings have plenty of frames, and the mastic around each one ages.
Merton is about 1 mile south-east of Wimbledon, in Greater London. For window mastic in and around Merton, please phone 0345 464 0079 or send us an email for a quick quote. We’re based in Crawley and cover Greater London, Merton included. Across Greater London, we cover 764 places, Merton among them. London is on our list too, around 7 miles away.
Here we cover the SW19 postcode area for window mastic. That includes homes and businesses on High Path, Pincott Road and Hayward Close and the roads around them. Merton is on the A24, so it’s easy for us to get to. Other places close to Merton include Merton Abbey (1 mile east), South Wimbledon (1 mile north-west), Colliers Wood (1 mile east), Tooting Bec (1 mile north-east) and Summerstown (1 mile north). Larger places within reach include London (7 miles north-east), City of Westminster (7 miles north), Marylebone (7 miles north), Kensington (6 miles north), St Pancras (8 miles north) and Shoreditch (9 miles north-east).
Near you in Merton
Typical jobs here are in homes near The Nelson Arms, Wimbledon School of Art and Wandle Park, among other places. Merton’s nearest station is Haydons Road station, roughly 0.8 miles north of the centre. Other landmarks nearby include Southside Wandsworth (2.8 miles north) and St George's Hospital (1.1 miles north-east). The countryside around Merton includes Henman Hill and Merton Park Green Walks.
Honest limits
New sealant cannot fix everything, and we’d rather say so up front. It will not solve:
- A door that needs adjusting, rehanging or new seals
- Damp problems in the wall away from the window
- Misting between the panes of a double-glazed unit (that needs a new unit)
Not sure which it is? You can phone 0345 464 0079 or send us an email and we’ll tell you honestly.
Surfaces we seal
- Window sills
- Composite doors
- Timber windows & doors
- Aluminium frames
- Patio & French doors
- uPVC windows
Keeping the joints in good condition
Looking after new joints is easy, and it makes a real difference:
- Wipe condensation off the frames
- Avoid harsh chemicals near the mastic
- Avoid blasting the frames with a pressure washer
- Keep paint off silicone joints
Wipe the frames with soapy water when you clean the windows, and keep solvents and harsh chemicals off the joint.
Wet, windy weather is when failed mastic shows itself, but sealant goes on best when frames and walls are dry. Dealing with it when you first notice a crack avoids chasing leaks through the wet months.
How it works
Once we are on site, we check the joints match what you told us. If we find something unexpected, we talk it through with you first. After that, the work takes most of a day for a typical house, less for a few frames. For a job in Merton, parking and access are the things to plan: let us know about parking, the floor we’ll be working on and any lift or shared entrance.
- First we look at every frame and agree the list.
- The old mastic is cut out and the surfaces cleaned back.
- Deep gaps are filled with backing rod to set the depth.
- New exterior sealant goes on in a matching colour and is tooled smooth.
- Every joint is checked before we leave.
Getting ready for the visit
- Try not to wet indoor joints just before the visit
- Mention any tricky access
- Keep children and pets away from the work area
Getting a quote
For window mastic in Merton, ring 0345 464 0079 or send us an email. Tell us what the problem is and where, and we’ll agree the price before any work begins.