Greater London · England
Window & door mastic in Dartmouth Park, Greater London
Window and door frames in Dartmouth Park need attention? We remove the old material, prepare the joints and seal them properly, and the work is guaranteed for a year.
- Cracked sealant at the sill ends
- Damp patches on the reveal after heavy rain
- Mastic that has split away from the wall
Window mastic for homes and businesses in Dartmouth Park
Over two decades of sealing frames has taught us which products suit which walls. We are ARBOMaster approved and fully insured, and every job is covered by a 12-month guarantee. We’re often asked to deal with a bead that doesn’t match the frame and whistling draughts around closed windows, across uPVC windows, aluminium frames and composite doors.
London’s Victorian and Edwardian terraces were built with timber sash windows, and many still have them or their replacements. Either way, the mastic between frame and brickwork is what stops draughts and rain getting in.
All of our work is guaranteed for twelve months, and the guarantee is the same wherever you are.
- Location
- Dartmouth Park (NW5, N19, N7)
- Wider area
- Greater London
- Cover
- A year, on every job
- Quote
- A clear price before work begins
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Questions from Dartmouth Park
I let a flat near Gospel Oak station. Can you help?
Yes, rental work is part of what we do. Just call 0345 464 0079 or send us an email and tell us about the property, and we will send you a clear quote.
Is parking a problem for a job in Dartmouth Park?
Parking in Dartmouth Park, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly.
Do you cover Dartmouth Park?
Yes. We’re based in Crawley and work across South East England, London and Scotland.
Can you seal over the old sealant?
No. Fresh sealant does not stick to old sealant, and it traps any mould or water underneath. We remove it all first.
When is the sealant fully cured?
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.
What do you need from me for a quote?
A short description and the location, plus photos if you have them. If we need more, we’ll ask.
Can you do the inside joint as well?
Yes. Plenty of draughts come through the inside joint as well as the outside, so it can be worth sealing both.
Will there be a smell?
There can be a smell while the sealant cures. Opening a window helps.
How the visit works
All our tools and materials come with us in the van. After a quick look at the joints together, we protect the area and start. It normally takes a morning for a couple of windows and a door. 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.
- First, we confirm safe access to each frame.
- All the failed sealant is cut away.
- The surfaces are cleaned and left dry.
- Backing rod fills deep voids and the sealant goes in on top.
- We tool the joint so water runs off, then clear up.
Before we arrive
- Where the joints are inside, avoid wetting them before we arrive
- Mention any tricky access
- Plan for the work area to be out of bounds to pets and children
Getting a quote
For a quick quote, get us on the phone, or email us if that’s easier. Describe what needs sealing and we will talk you through the work.
Read more
Aftercare tips
How long the joints last depends on use and care. Here’s what we suggest:
- Keep paint and stain on wooden frames in good order
- Paint up to the joint, not over it
- Ventilate rooms so frames don’t stay wet inside
- Walk round the house once a year and look at the joints
Have a look at the joints once a year, ideally after winter. Cracks and lifting edges are easy to spot early, and if anything looks wrong, just phone 0345 464 0079 or send us an email.
Draughts get worse, not better. As the old mastic shrinks further, more air gets through, and heat escapes around the frame. A new joint closes it up.
What sealant work cannot fix
We won’t take on work that won’t last, so here’s what sealant can’t put right:
- A sash or casement that will not close properly
- A failed sealed unit that has misted up
- Damp coming through the wall itself rather than the frame joint
Not sure which it is? You can ring 0345 464 0079 or drop us an email and we will tell you honestly before booking.
What we seal
- Timber windows & doors
- Patio & French doors
- Composite doors
- Aluminium frames
- uPVC windows
- Window sills
What affects the quote in Dartmouth Park
For a quick quote, just ask. What matters most is:
- Whether the work is at height
- The type of sealant required
- How many areas need sealing
- The number and length of the joints
Combining jobs into one visit usually makes better use of the time than several visits, so tell us about everything that needs sealing. We’ll give you a clear price for the lot.
What we need to know
A few details help us give you an accurate quote. When you ask for a quote, tell us:
- Photos by email, if that’s easy
- Where the job is, and your postcode
- What’s wrong with the joints now
- Any previous sealing or DIY work
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is. When it suits you, phone 0345 464 0079 or email us.
What the job involves on each surface
Aluminium frames
Coated aluminium needs a compatible sealant and we avoid acetoxy silicones, which can react with 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’ll tell you which suits your home.
Leave it or put it right?
The work is quick compared with the damage it prevents: it takes anything from an hour or two to a full day, depending on how many frames there are. Leave it until water is coming in and you may need plastering and decorating as well. In a flat in Dartmouth Park, failed sealant seldom stays inside your own four walls: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
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.
Why book with us
- A sealant colour to suit the surroundings
- White, clear, grey or another colour, product permitting
- Experience in homes, commercial sites and hotels
- Any old sealant cut out fully, not covered over
Take a look at how sealant jobs are priced or customer reviews.
Dartmouth Park homes and the weather
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 Witanhurst (about 0.8 miles north-west) nearby, there’s older building stock in the area around Dartmouth Park 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.
If you live in an older home near Church of St Mary Brookfield, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint. As a London address, Dartmouth Park can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Dartmouth Park is about 2 miles east of Hampstead, in Greater London. For window mastic in and around Dartmouth Park, please phone 0345 464 0079 or email us for a quick quote. We are based in Crawley and cover Greater London, Dartmouth Park included. Our Greater London coverage runs to 764 places, and Dartmouth Park is one of them.
Work in NW5, N19 and N7 works the same way as everywhere else we cover. You will find streets such as Hugo Road, Ward Road and Anson Road, all of which we cover. Nearby, we also carry out window mastic in Lissenden Gardens (1 mile south-west), Tufnell Park (1 mile east), Gospel Oak (1 mile south-west), Upper Holloway (1 mile north-east) and Highgate (1 mile north). Further out, we also cover London (5 miles south-east), City of Westminster (3 miles south), Marylebone (3 miles south), Kensington (5 miles south-west), St Pancras (3 miles south-east) and Shoreditch (4 miles south-east).
What’s near Dartmouth Park
Typical jobs here are in homes near The Dartmouth Arms, Whittington Park and Brookfield Primary School. You will also find Asanté Academy of Chinese Medicine (1.4 miles north) and Vaughan Williams Memorial Library (1.5 miles south). The nearest railway station is Gospel Oak station, roughly 0.5 miles south-west of the centre. Other landmarks nearby include O2 Centre (1.8 miles south-west) and Isokon Gallery (1 mile south-west). Open spaces near Dartmouth Park include Belsize Wood and Dartmouth Park Hill.
What we’re called out for in Dartmouth Park
On timber frames, paint and putty build up around the joint. Old mastic gets painted over and cracks under the paint, and timber moves with moisture as well as temperature.
The problems people normally mention when they call include:
- Damp patches on the reveal after heavy rain
- Gaps left after new windows were fitted
- Hard, cracked sealant around windows
- Gaps between the frame and the inside reveal
Managing a site like Acland Burghley School? Then the mastic around its windows and doors needs looking after like any other building’s.
What to look for in a quote
- Who does the work, and how experienced they are
- What insurance they hold
- Whether VAT is included
- Whether you can choose the colour