Greater London · England
Old Coulsdon Window Mastic
Mastic around window and door frames, sills and patio doors for Old Coulsdon, backed by a 12-month guarantee. Ask us for a quote.
- Gaps where the sill meets the wall
- A bead that does not match the frame
- Hard, cracked sealant around windows
Window mastic for homes and businesses in Old Coulsdon
Frames and walls do not move together. Heat and cold make frames grow and shrink against brick or render that hardly moves. So the sealant has to stretch and recover, which is why we use a low-modulus product. We work on uPVC windows, timber windows & doors and patio & French doors, and the jobs we see most are cold air getting in at the frame edge and cracked internal joints between frame and plaster.
London homes have every kind of window, from timber sashes in period terraces to aluminium and uPVC in newer blocks. Over the years, the sealant around them shrinks, cracks and pulls away, which is when draughts and damp patches appear in homes in Old Coulsdon.
A one-year guarantee comes as standard.
- Place
- Old Coulsdon (CR5, CR3, CR8)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
How the job changes by surface
Aluminium frames
Coated aluminium needs a compatible sealant, and acetoxy silicones aren’t used, as they can attack some metals. We use a neutral-cure product.
Timber windows & doors
Older timber windows in stone or brick can suit sand mastic rather than modern sealant. We can talk through the options.
Keeping the joints in good condition
Simple care keeps the joints in good condition. We recommend:
- Keep paint off silicone joints
- Make sure the drainage slots aren’t blocked
- Avoid blasting the frames with a pressure washer
- Wash the frames with mild soapy water
Timber frames need their paint kept up, since wood that gets wet swells and shrinks more. Keep paint off the silicone itself.
Signs to watch for: 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.
Work for landlords, hotels and businesses
Hotels need rooms back in use, so the work can be planned room by room around your bookings where we can. We have worked in hotels as well as homes and businesses.
We also work for property managers and facilities teams in Old Coulsdon and across Greater London. Several sites can go on one quote, and we are fully insured.
Places near Old Coulsdon
Other services in Old Coulsdon
What happens on the day
The work is kept neat 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 tell you how long to leave it before we go. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Old Coulsdon. A visitor permit or a nearby bay makes the visit run more smoothly.
- We start by checking each window and door with you.
- Next the failed sealant is cut away and the joint cleaned.
- 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.
Before we arrive
- Mention if the joints have been sealed before
- On commercial sites, let us know about site rules
- Where the joints are inside, avoid wetting them before we arrive
How to get a quote
Every job is quoted individually, so start by telling us what you need. Simply phone 0345 464 0079 or send us an email and describe the job, and pictures are welcome.
Advice
Common questions in Old Coulsdon
Do you cover Old Coulsdon for window mastic?
Yes. Our work covers London and the South East, and Old Coulsdon is part of that. You can phone 0345 464 0079 or drop us an email and tell us what needs doing.
Can you help a landlord with a rental near Coulsdon South station?
Yes, rental work is part of what we do. Just phone 0345 464 0079 or drop us an email and tell us about the property, and we’ll give you a clear price.
Do you seal inside as well as outside?
Yes. Outside is the weather seal; inside closes the gap to the plaster. We can do either or both.
Should I try DIY first?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Can resealing stop a draught around my window?
Yes, if the air is getting in around the frame. If it’s coming through the window seals, we’ll tell you.
How long will my window job take?
It depends on access, the old mastic and the size of the frames. You will know the timing when we quote.
Does the work come with a guarantee?
Yes, with our 12-month guarantee. Keeping drainage clear and checking the joints yearly helps them last.
What do you need from me for a quote?
Let us know what needs doing and where, with pictures by email if possible. We’ll ask anything else we need to know.
Old Coulsdon homes and the weather
London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. In a converted house or block, who looks after the windows depends on the lease, so check that before you book.
For site and facilities teams at buildings such as Keston Primary School, its window and door frames need their mastic kept sound, just like a home’s. If you live in an older home near Church of St John the Evangelist, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. For landlords with property near Coulsdon South station, renewing tired window mastic between tenants heads off draught and damp complaints.
Old Coulsdon is about 1 mile south-east of Coulsdon, in Greater London. Across the CR5 area, we cover window mastic for homes and businesses. Old Coulsdon is one of 764 places in Greater London where we work. London is on our list too, about 14 miles from Old Coulsdon.
All of CR5, CR3 and CR8 is within our area for window mastic. Streets in the area include Ellis Road, Tollers Lane and Court Avenue, and we cover them all. If you are just outside Old Coulsdon, we cover Coulsdon (1 mile north-west), Chipstead (2 miles west), Purley (2 miles north), Woodcote (2 miles north-west) and Woodmansterne (3 miles west). Further out, we also cover London (14 miles north), City of Westminster (15 miles north), Marylebone (15 miles north), Kensington (14 miles north), Whitechapel (15 miles north) and Brompton (14 miles north).
Landmarks near Old Coulsdon
Locally, jobs take us to homes and businesses close to Sunnydown School, Dollypers Hill and The Tudor Rose pub. For rail, the closest station is Coulsdon South station, about 1.4 miles north-west of the centre. Well-known places in the area include East Surrey Museum (2 miles south-east) and St Lawrence's Hospital (1.3 miles south-east). Not far away are Nore Hill and Mercers Lake.
What affects the quote in Old Coulsdon
Your quote is based on your job. We look at:
- Any mould that needs treating
- The number and length of the joints
- Working hours on commercial sites
- The product the joint needs
A failed joint rarely gets cheaper to fix by waiting, because water and mould keep working on it. If you are unsure, call 0345 464 0079 or drop us an email for an honest opinion and a quote.
Helping us quote
Photos help, but a description is a good start. Please mention:
- Whether it’s a home or a business
- Roughly how big the job is
- Any access issues, like height or stairs
- If someone has resealed it before
Quotes start with a quick conversation. Describe the problem, the location and the size of the job, and we’ll explain how we’d tackle it. When it suits you, ring 0345 464 0079 or email us.
Why deal with it now?
The work is quick compared with the damage it prevents: the visit takes most of a day for a typical house, less for a few frames. Wait for damp to appear and there may be plaster and decorating to sort out too. In a flat in Old Coulsdon, failed sealant seldom stays inside your own four walls: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
Homes and businesses are quoted the same way: how much there is to do, how we reach it and what it needs, along with when we can work on site. Ask us for a quote and we will go through it with you.
Why us?
- Any old sealant cut out fully, not covered over
- Full insurance on every job
- We agree the colour with you first
- Colour picked to suit the job
Take a look at our cost guide or customer reviews.
What sealant work cannot fix
Some problems need a builder, plumber or other trade rather than us:
- Soft or decayed wood in the frame
- Damp problems in the wall away from the window
- Broken hinges, locks or handles
Not sure which it is? You can call 0345 464 0079 or drop us an email and we’ll tell you honestly before booking.
Surfaces we seal
- Aluminium frames
- Window sills
- Patio & French doors
- Timber windows & doors
- uPVC windows
- Composite doors