Greater London · England
Sand mastic for sash & case windows in Grahame Park, Greater London
Window and door surrounds in Grahame Park need attention? We remove the old material, prepare the joints and seal them properly, with a one-year guarantee.
- Crumbling sand mastic round a window
- A silicone bead on a sash window that spoils the look
- Gaps where the frame meets the masonry
Sand mastic in Grahame Park, done properly
Our applicators renew the sand mastic around sash and case windows and doors in stone and brick. The old mastic is raked out, the joint is prepared and new mastic is shaped by hand. We work on sash and case windows, timber door frames and stone surrounds, and common reasons people get in touch are gaps round a timber door in stone or brick and modern sealant on a period surround.
London homes have every kind of window, from timber sashes in period terraces to aluminium and uPVC in newer blocks. The mastic around them dries out and cracks with age, letting in draughts and water.
A one-year guarantee comes as standard.
- Location
- Grahame Park (NW9, NW7, NW4)
- Wider area
- Greater London
- Guarantee
- A year, on every job
- Quotes
- A clear price before we start
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Aftercare tips
No joint lasts for ever, but care makes a real difference. Our tips:
- Keep sills and gutters clear so water drains away
- Plan mastic work ahead of painting
- Inspect the joints round the windows every year or so
- Leave the new mastic unpainted
Do not touch or press the mastic while it hardens. It forms a skin fairly soon, but takes longer to harden fully.
Sound mastic protects the frame. Once it fails, water can sit against the timber and timber that stays wet can rot.
How the job changes by surface
Period and listed homes
A traditional finish suits a period property, and sand mastic is one of them.
Stone surrounds
Old stone surrounds are often uneven, so the joint varies in width. Sand mastic is shaped by hand to suit.
How the visit works
You don’t need to clear the whole room or building before we come, just the space around the work. We protect the rest, and the work takes a few hours per window, depending on the condition of the joints for a typical job. In a London area like Grahame Park, the main things to plan are parking and access: tell us about permits, visitor bays or off-street space, which floor we’re working on and whether there’s a lift.
- First we agree which joints need doing.
- Old mastic and any loose material are raked out.
- We pack any deep voids first.
- The sand mastic is mixed and pressed into the joint by hand.
- We dress the finish so it sits neatly against the masonry.
Before we arrive
- Let us know about stairs, lifts or work at height
- Keep children and pets away from the work area
- Let us know about earlier repairs to the joints
Get a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints.
Related advice
Nearby places to Grahame Park
Other services in Grahame Park
Grahame Park questions
Is parking a problem for a job in Grahame Park?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
Can you help a landlord with a rental near Mill Hill Broadway station?
Yes. We work for letting agents and landlords as well as householders, and several properties can be quoted together. You can phone 0345 464 0079 or send us an email with the details for a clear quote.
Is there any odour?
Some sealants have a smell while they cure, which fades as it sets. Ventilation helps.
What exactly is sand mastic?
Sand plus a binder based on linseed oil. It’s applied by hand and finished to sit neatly against the masonry.
Can I choose the sealant colour?
In most cases you can choose. We will explain which colours are available.
Can new sealant go over the old?
No. The old sealant always comes out first, so the new sealant bonds properly.
Can you do several jobs on one visit?
Yes. Several rooms, windows or areas can go on one quote.
Does someone need to be in?
It depends on the job. For work indoors, someone needs to let us in, and for outside work we’ll agree access with you when we book.
Do you need sand mastic in Grahame Park?
Previous repairs in cement or silicone often trap water or crack away. They don’t suit the joint, and they usually need raking out.
These are the problems we are asked about most:
- Gaps between timber frames and stone or brick
- Mastic worn away on windows facing the weather
- Crumbling sand mastic round a window
- Modern sealant on a period surround
As a London address, Grahame Park can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Before booking anyone
- Whether VAT is included
- Whether they’re fully insured
- Whether they seal over old material or remove it
- How the surfaces are prepared before sealing
Honest limits
We’d rather tell you now than do work that won’t last, so these are the limits:
- Decisions on consent for listed homes
- Broken panes
- Sashes that need overhauling
If you’re not sure, just call 0345 464 0079 or drop us an email and we’ll give you a straight answer before you book.
What we seal
- Sash and case windows
- Tenement windows
- Brick reveals
- Period & listed homes
- Timber door frames
- Stone surrounds
Quotes for sand mastic in Grahame Park
The price is agreed before any work begins. It takes into account:
- Any working-time requirements on site
- How much there is to do
- The type of sealant required
- How much old sealant there is and how hard it is to remove
What you pay reflects the work, not a rough estimate. That is why we ask about the job first.
What we need to know
You do not need to know the technical terms. It helps if you can tell us:
- Any access issues, like height or stairs
- Photos by email, if that’s easy
- What’s wrong with the joints now
- Whether it’s a home or a business
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is, and we will talk you through what we’d do. Whenever you’re ready, ring 0345 464 0079 or email us.
Frames and glazing around Grahame Park
Historic houses like Heath Hall (about 3.5 miles south-east) are a reminder that the area around Grahame Park has older buildings as well as new. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic. In a converted house or block, who looks after the windows depends on the lease, so it’s worth checking before booking.
For landlords with property near Mill Hill Broadway station, cracked sand mastic around sash windows lets in the draughts tenants complain about. If you live in an older home near St Augustine Grahame Park, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Grahame Park is about 1 mile south-east of Burnt Oak, in Greater London. Grahame Park gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a one-year guarantee. Grahame Park is one of 764 places in Greater London where we work. There’s also a page for London, about 9 miles away.
Every address in NW9, NW7 and NW4 is covered for sand mastic. Sand mastic is available to properties on Hall Lane, Booth Road and Harrier Road and the roads around them. With the M1 close by, Grahame Park is simple for us to get to. Nearby, we also carry out sand mastic in Burnt Oak (1 mile north-west), Mill Hill (1 mile north), The Hale (2 miles north-west), Edgware (2 miles north-west) and Little Stanmore (2 miles west). Further out, we also cover London (9 miles south-east), City of Westminster (7 miles south-east), Marylebone (7 miles south-east), Kensington (7 miles south), St Pancras (7 miles south-east) and Shoreditch (9 miles south-east).
What’s near Grahame Park
In Grahame Park, that means homes and buildings near Sunny Hill Park, Blessed Dominic Catholic Primary School and The Greyhound pub, among other places. The closest station to Grahame Park is Mill Hill Broadway station, roughly 0.9 miles north. Other landmarks nearby include Broadwalk Centre (1.7 miles north-west) and Church Farmhouse Museum (0.8 miles south-east). The countryside around Grahame Park includes Copthall South Fields and Parliament Hill.
What happens if it’s left?
An open joint round the frame lets weather in. Left, water can reach the timber and the wall, so dealing with it now protects both. In a London flat, a failed joint rarely stays your problem alone: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
No two jobs are quite the same, so we quote each one individually. Size, access and the product the joint needs all play a part, and we will explain the quote if you ask.
Why Grahame Park customers choose us
- Domestic, commercial and hotel work
- ARBOMaster approved applicator
- Over 20 years’ experience
- Any old sealant cut out fully, not covered over
Take a look at what affects the cost or customer reviews.