Greater London · England
Window & door mastic in Herne Hill, Greater London
Mastic around window and door frames, sills and patio doors for Herne Hill, backed by a 12-month guarantee. Ask us for a quote.
- Gaps between the frame and the inside reveal
- Draughts coming in around windows and doors
- Leaking joints at the ends of sills
DIY sealant or a professional job?
If you are set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it does not work out, we can still put it right.
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
Window mastic in Herne Hill, done properly
Most frames have an outside joint and an inside one. The external joint is the weather seal; inside, the joint between frame and plaster stops draughts and tidies the reveal. Either or both can be done. Common call-outs are for draughts coming in around windows and doors and rushed sealant from a window installation, across patio & French doors, timber windows & doors and uPVC windows.
From mansion-block windows to modern glazing in new flats, London has every kind of frame. Over the years, the sealant around them shrinks, cracks and pulls away, letting in draughts and water.
A one-year guarantee comes as standard.
- Location
- Herne Hill (SE22, SW2, SE24)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Also near Herne Hill
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Herne Hill: your questions answered
Is parking an issue for window mastic in Herne Hill?
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.
I let a flat near North Dulwich station. Can you help?
Yes. We work for landlords and letting agents as well as householders, and several properties can go on one quote. Just ring 0345 464 0079 or email us with the address and what needs doing, and we will give you a clear price.
Will the old sealant be removed?
Yes. We cut out all the old sealant and clean the joint before applying anything new.
Which products 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 have insurance?
Yes, we’re fully insured for every job we do.
Can you reach windows above the ground floor?
Yes, where they can be reached safely. Tell us about access when you get in touch and we’ll plan for it.
Can you match the sealant to my frames?
Yes, we choose a colour to suit the frame. Grey and black frames get grey or black sealant, and wood-effect frames normally suit brown.
Will new mastic stop draughts?
It will if the frame joint is the problem. We find where the air is coming from before we reseal.
What we do, step by step
We keep the work tidy and contained to the joints we’re treating, 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, and we explain the cure time before we leave. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. Mention any building rules, key holders or managing agents when you book.
- Each frame is looked over and we agree which ones need resealing.
- The old mastic is cut out and scraped back to clean surfaces.
- Deep gaps get closed-cell backing rod to set the depth.
- The new sealant goes on in white, brown, anthracite grey, black or clear to suit.
- Every joint is tooled smooth and checked before we leave.
Before we arrive
- Tell us if parking is tricky
- Let us know about earlier repairs to the joints
- Let us know about stairs, lifts or work at height
Getting a quote
It all starts with a short chat. Describe the problem, the location and the size of the job. Whenever you’re ready, phone 0345 464 0079 or send us an email.
Advice
What we’re called out for in Herne Hill
Joint shape matters as much as the product. A skim of sealant over a wide gap soon tears, while a joint packed solid cannot stretch. Backing rod sets the right depth.
The most common problems we see are:
- Leaking joints at the ends of sills
- Draughty joints inside around the window
- White mastic on grey or black frames
- Rain getting in at the frame or under the sill
Rented homes near North Dulwich station change hands often, and renewing tired window mastic between tenants heads off draught and damp complaints.
What your quote should include
- Whether they’re fully insured
- How the surfaces are prepared before sealing
- Whether you can choose the colour
- Whether VAT is included
What sealant work can’t fix
New sealant cannot fix everything, and we’d rather say so up front. Sealant won’t put right:
- A failed sealed unit that has misted up
- Soft or decayed wood in the frame
- Broken hinges, locks or handles
If you are not sure, just call 0345 464 0079 or email us and we will give you a straight answer before booking.
What we seal
- Patio & French doors
- Aluminium frames
- Window sills
- Timber windows & doors
- Composite doors
- uPVC windows
Leave it or put it right?
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 older London homes, water behind a failed joint soaks into brick and timber without much sign, and once it shows in Herne Hill, the repair is bigger than a sealant job.
A few things move the cost up or down: how much old sealant there is and how stubborn it is, any mould to treat, and whether we need extra access for height. We take all of that into account in your quote.
What you get with us
- We agree the colour with you first
- 180+ five-star Google reviews
- We leave the area clean and tidy
- We never seal over old sealant
Take a look at what affects the cost and customer reviews.
Windows and doors in Herne Hill
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. Historic houses like Kingswood House (about 1.7 miles south) are a reminder that the area around Herne Hill has older buildings as well as new. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
If you live in an older home near Saint Faith's, the joint between an old wall and a newer frame is generally the first place rain gets in. Schools such as Judith Kerr Primary School are buildings too, and the mastic around its windows and doors needs looking after like any other building’s.
Herne Hill is about 3 miles south of London, in Greater London. For window mastic in and around Herne Hill, it’s easy to get a quote: please phone 0345 464 0079 or drop us an email. We are based in Crawley and cover Greater London. We cover 764 towns and villages across Greater London, large and small.
Jobs for window mastic in SE22, SW2 and SE24 is quoted and booked the same way as anywhere else. Whether your property is on Jelf Road, Dewey Lane and Talma Road or anywhere close by, our applicators can take on the job. Main roads around Herne Hill include the A204 and A2214. Other places close to Herne Hill include Dulwich Village (1 mile south-east), East Dulwich (1 mile north-east), Dulwich (1 mile south-east), Denmark Hill (1 mile north) and Camberwell (1 mile north). We also work in nearby towns such as London (3 miles north), City of Westminster (5 miles north-west), Marylebone (5 miles north-west), Kensington (6 miles north-west), St Pancras (5 miles north) and Shoreditch (5 miles north).
What’s near Herne Hill
Locally, jobs take us to homes and businesses close to The Charter School, Half Moon pub and Belair Park. There’s a railway station in Herne Hill itself: North Dulwich station. Nearby you’ll also find Surrey Quays Shopping Centre (3.5 miles north-east) and House of Dreams Museum (0.7 miles north-east). For a walk, there’s Battersea Park Lake and Knight's Hill.
How we quote for window mastic
We quote each job individually. This is what makes a difference:
- How easy the joints are to reach
- Which sealant suits the joint
- When we can work, for business premises
- The old material and how stubborn it is
No two jobs are quite the same, so each one gets its own quote. Size, access and the product the joint needs all make a difference, and we’ll explain the quote if you ask.
Asking for a quote
When you call or email, it’s useful to know:
- Roughly how big the job is
- Access, such as stairs, a lift or height
- The type of property
- Photos by email, if that’s easy
There’s no standard price list. Instead, we give you a clear price for your job. To arrange one, ring 0345 464 0079 or send us an email.
Work for landlords, hotels and businesses
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance.
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements.