Greater London · England
Window Mastic in Kidbrooke
Mastic around window and door frames, sills and patio doors for homes and businesses in Kidbrooke and across Greater London. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Rain getting in at the frame or under the sill
- Gaps left after new windows were fitted
- Hard, cracked sealant around windows
Window mastic for homes and businesses in Kidbrooke
Whether it’s one leaking patio door or every frame on the house, the work is priced before anything is done. Just phone 0345 464 0079 or drop us an email and tell us how many frames there are and how they’re reached. Common call-outs are for gaps where the sill meets the wall and black, perished sealant on frames, on uPVC windows, aluminium frames and patio & French doors.
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 Kidbrooke as anywhere.
Every job is covered by our one-year guarantee, wherever you are in Greater London.
- Place
- Kidbrooke (SE3, SE9, SE18)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quote
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Different surfaces, different methods
Timber windows & doors
Where timber has rotted at the joint, it needs repairing first. If we find rot, we’ll tell you before going ahead, as a joiner will need to deal with it.
Aluminium frames
Coated aluminium needs a compatible sealant. We use a neutral-cure product.
What happens if it’s left?
Redecorating is a good moment to renew the mastic. Fresh joints finish the job neatly. 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 Kidbrooke.
Leaving a failed joint normally makes the job bigger, not smaller, because water and mould keep working on it. If you’re not sure whether it needs doing, phone 0345 464 0079 or drop us an email for an honest opinion and a quote.
Why choose Mr Mastic in Kidbrooke
- ARBOMaster approved applicator
- A choice of colours where the product allows
- We are fully insured
- 4.9 on Google from 180+ five-star reviews
Take a look at our cost guide or our reviews.
What happens on the day
There is not much for you to do on the day. Point us to the joints and we’ll get on with it. The work itself takes a few hours for a few frames, or a day or more for a whole house, including the tidy-up. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- We check each frame and agree which ones need doing.
- 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.
How to prepare
- Mention any parking rules near the property
- Mention if the joints have been sealed before
- On commercial sites, let us know about site rules
Ask for a quote
Want a quote for window mastic? Please call 0345 464 0079 or email us with a few details. We’ll explain what we’d do and send you a clear quote before we start.
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Kidbrooke: your questions answered
I let a flat near Kidbrooke station. Can you help?
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 will give you a clear quote.
Can parking be tricky for a visit in Kidbrooke?
Parking in Kidbrooke, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
Do you work on first-floor windows?
Yes, where it’s safe. Higher or awkward frames may need extra access, and we’ll confirm what’s needed.
Will there be a smell?
Sometimes, a little. It fades as the sealant cures, and ventilation helps.
How do I get a quote for window mastic in Kidbrooke?
The cost depends on the size of the job, access and how much old sealant has to come out. Ask us for a quote and we’ll talk you through it.
Will you leave a mess?
No. We work neatly, protect the area around the joints and tidy up afterwards.
What sealant do you use?
Quality sealants from brands including Arbo and Everbuild, picked for each joint. We’ll tell you what we are using and why.
Do you seal inside as well as outside?
Yes, we do both. Indoors, we seal between the frame and the plaster or reveal, using a paintable sealant if you want to decorate.
Landlord and commercial work in Kidbrooke
We also work for property managers and facilities teams in Kidbrooke and across Greater London. Several sites can be quoted together.
If you manage several properties in or around Kidbrooke, several properties can go on one quote. Send us the addresses and the work at each.
Aftercare tips
No joint lasts for ever, but care makes a real difference. A few tips:
- Avoid harsh chemicals near the mastic
- Walk round the house once a year and look at the joints
- Ventilate rooms so frames don’t stay wet inside
- Do not paint over the silicone
Check the drainage slots in the frames are not blocked, so water can run away instead of sitting against the joint.
A failed joint lets water into the wall a little at a time. You might not see it until plaster blows or a damp patch appears inside. Catching it early keeps the fix to a reseal.
When to call us in Kidbrooke
Sills take more water than any other part of a window, so the sill ends and the joint below the frame are common leak points. Failed sealant there lets rain into the wall or behind the frame.
Keep an eye out for any of the following:
- Mastic that’s falling out in pieces
- Draughty joints inside around the window
- White mastic on grey or black frames
- Water coming in at the bottom corners of a door
As a London address, Kidbrooke can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Questions to ask before booking
- What the quote includes, VAT included or not
- What happens if the job turns out different
- Which sealant they’ll use, and why
- Who does the work, and how experienced they are
Should I try it myself first?
A DIY attempt doesn’t rule out a professional job. We cut it out and start again.
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.
Kidbrooke homes and the weather
Historic houses like Eltham Palace (about 1.3 miles south) are a reminder that the area around Kidbrooke has older buildings as well as new. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window. 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.
Managing a site like Henwick Primary School? Then the mastic around its windows and doors needs looking after like any other building’s. Letting a property close to Kidbrooke station? Then sound mastic around windows and doors keeps out the draughts and damp that tenants notice first.
Kidbrooke is about 2 miles north of Eltham, in Greater London. Jobs in Kidbrooke 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, and Kidbrooke is one of them. There’s also a page for London, about 6 miles away.
Work in SE3, SE9 and SE18 is quoted and booked the same way as anywhere else. If you need window mastic at a property on Brome Road, Briset Road and Nesbit Road or a nearby road, we can help. Neighbouring places we cover for window mastic include Well Hall (1 mile south-east), Shooter's Hill (1 mile east), Middle Park (1 mile south), Horn Park (1 mile south-west) and Blackheath (1 mile west). We also work in nearby towns such as London (6 miles west), City of Westminster (9 miles west), Marylebone (9 miles north-west), Kensington (11 miles west), St Pancras (8 miles north-west) and Shoreditch (7 miles north-west).
Local landmarks in Kidbrooke
In Kidbrooke, that means homes and buildings near Thomas Tallis School, The Halley Academy and Eltham Common, among other places. For rail, the closest station is Kidbrooke station, about 0.7 miles west of the centre. Well-known places in the area include Brook General Hospital (0.5 miles north-east) and Lewisham Shopping Centre (2.4 miles west). Open spaces near Kidbrooke include Birdbrook Road Nature Reserve and Summer Hill.