Greater London · England
Kevington Window Mastic
Window mastic across Kevington and nearby, with every bit of old sealant taken out first and a one-year guarantee.
- Cracked or shrunken mastic around the frame
- Water coming in at the bottom corners of a door
- Rushed sealant from a window installation
Window mastic in Kevington: local notes
Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. With historic houses such as Lullingstone Castle (about 3.2 miles south-east) nearby, there’s older building stock in the area around Kevington 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.
Rented homes near St Mary Cray station change hands often, and renewing tired window mastic between tenants heads off draught and damp complaints. Homes close to Unity Church include some older properties, and frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Kevington is about 1 mile east of Orpington, in Greater London. Jobs in Kevington get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Our Greater London coverage runs to 764 places, Kevington among them. You can also see our page for London, about 13 miles away.
All of BR5 is within our area for window mastic. Whether your property is on Crockenhill Road and Sheepcote Lane or a nearby road, our applicators can take on the job. Close by, we work in Derry Downs (1 mile west), Crockenhill (1 mile east), St Mary Cray (1 mile west), Orpington (1 mile west) and Poverest (2 miles west). We also work in nearby towns such as London (13 miles north-west), City of Westminster (15 miles north-west), Marylebone (15 miles north-west), St Pancras (15 miles north-west), Shoreditch (13 miles north-west) and Walthamstow (15 miles north-west).
Landmarks near Kevington
Typical jobs here are in homes near The Priory School and Harris Academy Orpington and the streets around them. The closest station to Kevington is St Mary Cray station, roughly 1.4 miles north-west. A little further out are Lullingstone Castle (3.2 miles south-east) and London Borough of Bromley Museum (1.5 miles west). Not far away are Summer Hill and The Warren.
Window mastic in Kevington
From a single sill to a whole house of windows, the work is priced before anything is done. Just call 0345 464 0079 or drop us an email and tell us how many frames there are and how they’re reached. If you are dealing with cracked internal joints between frame and plaster and white mastic on grey or black frames, 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 usually says who is responsible for the windows, so it’s worth checking before booking.
Every job is covered by our 12-month guarantee, wherever you are in Greater London.
- Where
- Kevington (BR5)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Quotes
- A clear quote up front
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Keeping the joints in good condition
No joint lasts for ever, but care makes a real difference. Our tips:
- Don’t aim a pressure washer at the joints
- Use gentle cleaners on frames and sealant
- Keep solvents and bleach off the sealant
- Look round the frames every year or so
Timber frames need their paint kept up, because bare, wet timber moves more and pulls at the joint. Paint up to the joint, not over the silicone.
Look out for the warning signs: split or missing mastic, gaps, damp patches inside or black mould on the reveal. Any of these is worth a call.
Common questions in Kevington
I let a flat near St Mary Cray station. Can you help?
Yes. We work for landlords and agents as well as householders. Just call 0345 464 0079 or drop us an email with the address and what needs doing, and we’ll give you a clear quote.
Can parking be tricky for a visit in Kevington?
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.
How many windows can you do in a day?
A few frames take a few hours. You’ll get a timescale with the quote.
How long should I leave it?
Many sealants skin over quickly but take longer to cure fully. We will give you the cure time for the product we used before we leave.
Are you an approved applicator?
Yes. We hold ARBOMaster approved applicator status, and we are fully insured.
What does window mastic cost?
There’s no set price, as it depends on the job: its size, the old material, access and the product needed. You will get a clear quote before any work starts.
Do the sealants smell?
That depends on the sealant. Some smell for a while, some hardly at all, and any smell fades as they cure.
Does someone need to be in?
If the work is inside, we need someone to let us in. Once we’ve agreed the job, you do not need to watch us work.
Why deal with it now?
Not every sealant suits a window. Interior caulk and bathroom silicone aren’t made for exterior frame joints. An exterior, low-modulus sealant stays flexible in sun and frost. 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. Dealing with it early is far simpler for homes in Kevington.
The cost reflects the work involved, not guesswork. That is why we ask a few questions first and give you a clear quote before work begins.
Why choose Mr Mastic in Kevington
- White, clear, grey or coloured to suit, where the product allows
- Neat joints and a tidy finish
- Every job guaranteed for a year
- Any old sealant cut out fully, not covered over
Read what affects the cost and what customers say.
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. We prepare and reseal every joint, backing the deep ones.
Window sills
Stone and concrete sills have their own joints, and the joint under the frame can let rain run behind. We seal those with a sealant suited to masonry.
Common problems we fix in Kevington
Mastic ages in the weather. UV light hardens the outside of the bead, and over the years it loses its give, cracks and comes away.
Most people get in touch when they notice one of these:
- Sealant in the wrong colour for the frame
- Leaking joints at the ends of sills
- Whistling draughts around closed windows
- Hard, cracked sealant around windows
As a London address, Kevington can be tricky for parking: let us know about parking bays, permits or a driveway.
What to look for in a quote
- How the surfaces are prepared before sealing
- Whether they’re fully insured
- What the quote includes, VAT included or not
- Whether you can choose the colour
DIY sealant or a professional job?
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
Nearby places to Kevington
Also in Kevington
What we do, step by step
We keep the work tidy and contained to the area we are working on, so you can carry on as normal. Expect the work to take anything from an hour or two to a full day, depending on how many frames there are. In Kevington, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- We check each frame and agree which ones need doing.
- Next the failed sealant is cut away and the joint cleaned.
- Where gaps are deep, backing rod goes in first.
- New exterior sealant goes on in a matching colour and is tooled smooth.
- Finally we tidy up and check each joint.
Before we arrive
- Keep children and pets away from the work area
- Tell us about any previous sealing or DIY attempts
- For business premises, tell us about site rules or sign-in
Get a quote
Want a quote for window mastic? Please call 0345 464 0079 or email us and tell us about the job. We will explain what we’d do and send you a clear quote before we start.
Related advice
What sealant work cannot fix
Some problems need a builder, plumber or other trade rather than us:
- Condensation trapped between the panes
- Damp problems in the wall away from the window
- Faulty window hardware
If in doubt, ring 0345 464 0079 or send us an email and we will say what we think.
Joints and surfaces we work on
- uPVC windows
- Composite doors
- Timber windows & doors
- Aluminium frames
- Patio & French doors
- Window sills