Greater London · England
Window & door mastic in Nash, Greater London
Window and door frames in Nash need attention? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- A bead that doesn’t match the frame
- Mastic that is falling out in pieces
- Leaking joints at the ends of sills
How we handle window mastic in Nash
Frames and walls don’t move together. Plastic and aluminium frames move with the temperature, while masonry stays fairly still. That’s why the joint needs a flexible, low-modulus sealant rather than something rigid. If you have draughts coming in around windows and doors and rain getting in at the frame or under the sill, we can help.
Much of London’s older housing was built with timber sash windows, some still in place and some long since replaced. Either way, the mastic between frame and brickwork is what stops draughts and rain getting in, in Nash as anywhere.
The work is guaranteed for twelve months. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Where
- Nash (BR2)
- Region
- Greater London
- Cover
- A year, on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Why it’s worth doing now in Nash
Resealing frames is a short job: it 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 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 Nash.
What you pay reflects the work, not a rough estimate. That is why we ask about the job first and agree the price before starting.
Why choose Mr Mastic in Nash
- Domestic, commercial and hotel work
- Sealant colour chosen to suit
- Quality sealants from Arbo and Everbuild
- Anti-fungal silicone where joints get wet
See how sealant jobs are priced and our reviews.
Looking after it afterwards
No joint lasts for ever, but care makes a real difference. A few tips:
- Keep paint and stain on wooden frames in good order
- Keep solvents and bleach off the sealant
- Paint up to the joint, not over it
- Check the mastic once a year
Try not to touch the new joint while it cures, for as long as we advise. Do not point a pressure washer at the joints.
On timber windows, water behind the joint can lead to rot. Rotten timber needs a joiner, not a sealant, so it pays to reseal before that happens.
Should I try it myself first?
If you’re 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.
If you’ve already had a go yourself, that is fine. We cut it out and start again, so tell us about it when you ask for a quote.
Work for landlords, hotels and businesses
Mouldy or split sealant often shows up at the end of a tenancy, and it’s quick to put right between tenancies. We can quote for more than one property at once.
Water getting past a failed joint can damage the building, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance.
Other services in Nash
How the visit works
There is not much for you to do on the day. Point us to the joints and we will get on with it. The work itself takes anything from an hour or two to a full day, depending on how many frames there are. In Nash, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- First, we go round the frames with you and agree the list.
- The old mastic is cut out and scraped back to clean surfaces.
- Where the gap is deep, backing rod goes in first.
- 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.
Preparing for the visit
- Mention any parking rules near the property
- Keep children and pets away from the work area
- Mention any sign-in or site rules at work premises
Ask for a quote
Want a quote for window mastic? Please call 0345 464 0079 or send us an email with a few details. You will know what we plan to do, and what it will cost, before any work begins.
Advice
Common problems we fix in Nash
A lot of older mastic was never designed to stay flexible. Once it has hardened, the frame’s movement tears it from the wall, leaving a hairline gap down one side.
Look out for these signs:
- Leaking joints at the ends of sills
- Rain getting in at the frame or under the sill
- Whistling draughts around closed windows
- Rushed sealant from a window installation
For site and facilities teams at buildings such as Wickham Common Primary School, the mastic around its windows and doors needs looking after like any other building’s.
What your quote should include
- Whether you can choose the colour
- What happens if they find a problem under the old sealant
- What insurance they hold
- Whether they seal over old material or remove it
What sealant work cannot fix
We won’t take on work that will not last, so here’s what sealant cannot put right:
- A frame that has rotted at the joint
- Broken hinges, locks or handles
- Penetrating damp from a failed cavity tray or render
Not sure which it is? You can call 0345 464 0079 or drop us an email and we will tell you honestly.
Where we work in Nash
- uPVC windows
- Aluminium frames
- Patio & French doors
- Timber windows & doors
- Composite doors
- Window sills
Nash questions
Can you help a landlord with a rental near Hayes (Kent) station?
Yes, we work for letting agents and landlords. You can phone 0345 464 0079 or drop us an email with the address and a few details, and we will give you a fixed price before work begins.
Can parking be tricky for a visit in Nash?
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.
Can you reach windows above the ground floor?
Yes, if safe access is possible. For high or awkward windows, we’ll tell you what access is needed.
Do I have to be there?
It depends on the job. For work indoors, someone needs to let us in, while outside work can sometimes be arranged differently.
Where are you based?
We work from Crawley. We cover Nash and the rest of Greater London, along with the rest of our area.
Can you do the inside joint as well?
Yes. Indoors, we seal between the frame and the plaster or reveal, using a paintable sealant if you want to decorate.
Is the work guaranteed?
Yes. Each job is covered for 12 months.
Do you work for hotels and businesses?
Yes. We have worked for hotels, offices and other businesses, and we’re fully insured.
Nash homes and the weather
With historic houses such as Down House (about 2.4 miles south-east) nearby, there’s older building stock in the area around Nash 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. In London conversions and blocks, the lease decides who is responsible for the frames, so it’s worth checking before booking.
As a London address, Nash can be tricky for parking: let us know about parking bays, permits or a driveway. For an older house near a landmark such as Keston Parish Church, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Nash is about 3 miles south of Bromley, in Greater London. Every kind of property in Nash can book us for window mastic. Every job comes with our 12-month guarantee. Nash is one of 764 places in Greater London we cover for window mastic. You can also see our page for London, about 11 miles away.
Our applicators cover all of the BR2 postcode area for window mastic and the streets around it. Whether your property is on Nash Lane and North Pole Lane or a nearby road, we can help. We also cover Keston (1 mile east), Leaves Green (1 mile south-east), Hayes (1 mile north), New Addington (2 miles south-west) and Farthing Street (2 miles south-east). Within a short drive, we also cover London (11 miles north-west), City of Westminster (13 miles north-west), Marylebone (13 miles north-west), Kensington (14 miles north-west), St Pancras (13 miles north-west) and Shoreditch (12 miles north).
Landmarks near Nash
We work in homes and buildings around The Greyhound pub, All Saints Catholic School and Coney Hall Recreation Ground and the streets around them. The closest station to Nash is Hayes (Kent) station, roughly 1.4 miles north. Well-known places in the area include The Mall (3.2 miles north) and Bethlem Museum of the Mind (1.8 miles north). For a walk, there’s Hutchinson's Bank and Summer Hill.