Greater London · England
Window & door mastic in Dancers Hill, Greater London
Window and door frames in Dancers Hill need attention? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Leaking joints at the ends of sills
- Mastic that is falling out in pieces
- Untidy mastic left by window fitters
Window mastic in Dancers Hill
If you can feel air around a shut window, the gap is often at the frame. Resealing that joint can make a room feel noticeably less draughty and quietens the whistle on windy days. Where the air is getting in through the window itself, we will say so. If you’re dealing with gaps left after new windows were fitted and damp patches on the reveal after heavy rain, we can put it right.
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 Dancers Hill.
You are covered for a year from the day we finish. If anything isn’t right with it, call 0345 464 0079 or email us.
- Place
- Dancers Hill (EN5)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quote
- A clear price before work begins
- Call
- 0345 464 0079
- Updated
- 26 October 2026
For landlords and businesses
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements.
Mouldy or split sealant often shows up at the end of a tenancy, and it’s easy to sort out between tenants. Several properties can be quoted together.
Window mastic in Dancers Hill: local notes
With historic houses such as Wyllyotts Manor (about 1.5 miles north-east) nearby, there’s older building stock in the area around Dancers Hill as well as newer homes. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic. Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Wyllyotts Manor, about 1.5 miles north-east, is one of the historic houses in the wider area around Dancers Hill, and older homes nearby need a sealant that suits their walls. Dancers Hill is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book.
Dancers Hill is about 2 miles south-west of Potters Bar, in Greater London. For window mastic in and around Dancers Hill, it’s easy to get a quote: please call 0345 464 0079 or send us an email. We cover Greater London from our Crawley base, Dancers Hill included. Dancers Hill is one of 764 towns and villages in Greater London we cover for window mastic. Our London page covers work nearby.
Our applicators cover all of the EN5 postcode area for window mastic. If you’re just outside Dancers Hill, we cover Kitts End (1 mile south-east), South Mimms (1 mile north-west), Ridge (1 mile north-west), High Barnet (2 miles south) and Hadley (2 miles south). Further out, we also cover London (14 miles south), City of Westminster (12 miles south), Marylebone (12 miles south), Kensington (12 miles south), St Pancras (11 miles south) and Shoreditch (12 miles south-east).
Landmarks near Dancers Hill
In Dancers Hill, that means homes and buildings near King George's Fields (Monken Hadley), Pope Paul Catholic Primary School and The Green Dragon Public House, among other places. The nearest railway station is Potters Bar station, about 1.5 miles north-east. Well-known places in the area include Barnet General Hospital (2.1 miles south) and Spires Shopping Centre (1.8 miles south). Open spaces near Dancers Hill include Darland's Lake and Hadley Green.
How the job changes by surface
uPVC windows
Plastic frames move a lot between a hot afternoon and a cold night, so we use a flexible, low-modulus sealant. We match white, brown, anthracite grey and black frames.
Patio & French doors
Heavy door frames can move more than windows. The sealant must cope with it without cracking.
Common questions in Dancers Hill
Can parking be tricky for a visit in Dancers Hill?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly.
Do you work for landlords with property near Potters Bar station?
Yes, landlords and agents are among the people we work for. You can ring 0345 464 0079 or email us with the details for a clear quote.
Do you hold any approvals?
Yes. ARBOMaster is the approved applicator scheme for Arbo sealants, and we are part of it.
Is there any odour?
Possibly a little. Any smell clears as the sealant cures.
Where is Mr Mastic based?
Our base is in Crawley, and we cover South East England, London and all of Scotland.
What sealant do you use?
We choose the sealant for the joint, not the other way round. Where it moves, gets wet or faces the weather makes a difference, and we will tell you what we’re using.
Does the work come with a guarantee?
Yes. All our work carries a 12-month guarantee, and we’re fully insured.
Do I need to be at home?
If the work is inside, we need someone to let us in. Once we’ve agreed the job, you don’t need to watch us work.
Aftercare tips
Once the sealant has cured, a few habits help it last:
- Do not paint over the silicone
- Clean frames with a soft cloth and soapy water
- Avoid blasting the frames with a pressure washer
- Keep drainage slots and sill grooves clear
Check the drainage slots in the frames aren’t blocked, so rain drains out rather than building up at the sealant.
Signs to watch for: split or missing mastic, gaps, damp patches inside or black mould on the reveal. Any of these is worth a call.
Also near Dancers Hill
What else we do in Dancers Hill
Should I try it myself first?
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
If you’ve already had a go yourself, that’s fine. We cut it out and start again.
When to call us in Dancers Hill
Sun, frost and rain wear sealant out. Sunlight dries the surface out, until it loses its stretch and starts to crack.
Look out for these signs:
- Untidy mastic left by window fitters
- Mastic that’s falling out in pieces
- Draughty joints inside around the window
- Whistling draughts around closed windows
If you look after a building such as Dame Alice Owen's School, larger buildings have plenty of frames, and the mastic around each one ages.
What your quote should include
- Are they insured?
- What product goes in the joint
- How much experience the applicator has
- Is VAT in the price?
When something else is needed
Some problems need a builder, plumber or other trade rather than us:
- Damp coming through the wall itself rather than the frame joint
- A frame that has rotted at the joint
- A door that needs adjusting, rehanging or new seals
If in doubt, call 0345 464 0079 or drop us an email and we will say what we think before booking.
Surfaces we seal
- Timber windows & doors
- Patio & French doors
- uPVC windows
- Composite doors
- Aluminium frames
- Window sills
How it works
All our tools and materials come with us in the van, so you do not need to buy or prepare anything. Once we’ve agreed what’s being done, the area is protected and the work begins. It normally takes anything from an hour or two to a full day, depending on how many frames there are. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Dancers Hill. It helps if you can point us to a visitor permit or a bay close to the door.
- We check each frame and agree which ones need doing.
- The old mastic is cut out and the surfaces cleaned back.
- We fit backing rod in deep gaps so the sealant is the right depth.
- We apply a weatherproof sealant to match the frame and tool it neatly.
- Every joint is checked before we leave.
Preparing for the visit
- Let us know about earlier repairs to the joints
- Mention any parking rules near the property
- Plan for the work area to be out of bounds to pets and children
Get a quote
Getting a quote is simple: let us know the job and the location, and roughly how big it is. Photos by email help us understand the job, and we will take it from there.