Greater London · England
Sand mastic for sash & case windows in Hampstead Garden Suburb, Greater London
Professional sand mastic in and around Hampstead Garden Suburb, with every bit of old sealant taken out first and a one-year guarantee.
- Crumbling sand mastic round a window
- Failed mastic on an exposed elevation
- Tired mastic found when preparing windows for paint
Honest limits
We will not take on work that will not last, so these are the limits:
- Timber that has rotted
- Sashes that rattle, stick or won’t open
- Broken panes
If you’re not sure, just call 0345 464 0079 or email us and we will give you a straight answer before booking.
Surfaces we seal
- Period & listed homes
- Brick reveals
- Sash and case windows
- Timber door frames
- Tenement windows
- Stone surrounds
Sand mastic in Hampstead Garden Suburb
We work across Hampstead Garden Suburb renewing sand mastic on sash windows and doors. Every joint is cleaned out and filled by hand for a neat, traditional finish. We are often asked to deal with old sand mastic that has cracked, crumbled or fallen out and mastic that needs renewing before redecorating, across period & listed homes, sash and case windows and stone surrounds.
Much of London’s older housing was built with timber sash windows, some still in place and some long since replaced. Whatever is in the opening now, the joint between frame and wall is what keeps the weather out.
The work is covered for a year after we finish. If anything isn’t right with it, call 0345 464 0079 or send us an email.
- Place
- Hampstead Garden Suburb (NW11, N2, N3)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before work begins
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
What happens on the day
On the day, there’s very little for you to do. Point us to the joints and we’ll get on with it. The job generally takes a few hours for a single window, longer for several, including the tidy-up. In Hampstead Garden Suburb, as in most of London, parking needs a little planning. It helps if you can point us to a visitor permit or a bay close to the door.
- We start by checking each surround and agreeing the joints to renew.
- We rake out the old mastic and clean the joint.
- We pack any deep gaps so the mastic sits at the right depth.
- We mix the sand mastic and apply it by hand, shaping it to the joint.
- We dress the surface so it sits neatly against the masonry.
How to prepare
- Tell us about access, such as stairs, a lift or high-level joints
- Mention any sign-in or site rules at work premises
- Keep children and pets away from the work area
Ask for a quote
Getting a quote is simple: let us know the job and the location and its rough size. A few photos by email make the job easier to understand.
Read more
How to look after the new joints
Once the sealant has cured, a few habits help it last:
- Plan mastic work ahead of painting
- Get any rot dealt with first
- Ask the planning authority about consent for listed or conservation-area homes
- Don’t run silicone over sand mastic
Keep gutters and sills clear so water runs away from the surround. Constant wetting wears the mastic faster.
Small cracks are a sign the mastic is ageing. It’s easier to renew it before it drops out.
Different surfaces, different methods
Period and listed homes
Period homes look their best with traditional materials.
Sash and case windows
The box of a sash and case window sits in the stone or brick opening. Sand mastic seals the joint round it.
Hampstead Garden Suburb homes and the weather
London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. In a converted house or block, who looks after the windows depends on the lease, so check that before you book.
If you look after a building such as The Henrietta Barnett School, the mastic around its windows and doors needs looking after like any other building’s. Rented homes near Brent Cross West station change hands often, and older sash windows in a rental need their mastic kept sound to keep the weather out. As a London address, Hampstead Garden Suburb can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Hampstead Garden Suburb is about 1 mile south-west of East Finchley, in Greater London. For sand mastic in and around Hampstead Garden Suburb, it’s easy to get a quote: please ring 0345 464 0079 or send us an email. We are based in Crawley and cover Greater London, Hampstead Garden Suburb included. Our Greater London coverage runs to 764 places, Hampstead Garden Suburb among them. There’s also a page for London, roughly 7 miles from Hampstead Garden Suburb.
Work in NW11, N2 and N3 works the same way as everywhere else we cover. You’ll find streets such as Maya Road, Oakwood Road and Bigwood Road, and we cover them all. Being close to the A1, Hampstead Garden Suburb is simple for us to get to for sand mastic. We also cover the places around Hampstead Garden Suburb: Temple Fortune (1 mile west), East Finchley (1 mile north-east), Golders Green (1 mile south-west), North End (1 mile south) and Vale of Health (1 mile south). Within a short drive, we also cover London (7 miles south-east), City of Westminster (5 miles south), Marylebone (5 miles south), Kensington (6 miles south), St Pancras (5 miles south-east) and Shoreditch (6 miles south-east).
Around Hampstead Garden Suburb
Locally, jobs take us to homes and businesses close to The Old White Lion pub, Brookland Infant and Nursery School and Lyttelton Playing Fields, among other places. Hampstead Garden Suburb’s nearest station is Brent Cross West station, about 2.1 miles south-west of the centre. A little further out are Brent Cross Shopping Centre (1.7 miles west) and Jewish Museum - Finchley (0.9 miles north). For a walk, there’s Darland's Lake and Parliament Hill.
What affects the quote in Hampstead Garden Suburb
For a quick quote, just ask. What matters most is:
- The number of rooms or windows
- Access and height
- When we can work, for business premises
- Mould in or behind the old joints
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 the work is at height. Your quote takes all of that into account.
Helping us quote
Before you ask for a quote, have a think about:
- How we’d reach the joints
- The rough size of the job
- The type of property
- Photos by email, if that is easy
For sand mastic in Hampstead Garden Suburb, call 0345 464 0079 or drop us an email. A short description of the job and where it is helps us quote, and you’ll get a clear quote before we start.
Why act early in Hampstead Garden Suburb
Cement-based fillers and modern sealants do not always suit a period surround. Sand mastic is the like-for-like choice and that can be important for listed homes. 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 Hampstead Garden Suburb.
What it costs depends on how much there is to do, how much old material has to come out and access to the work. We give a clear quote before any work starts.
What you get with us
- Trusted Arbo and Everbuild sealants
- ARBOMaster approved applicator
- Every job guaranteed for a year
- Any old sealant cut out fully, not covered over
See what affects the cost and what customers say.
Nearby places to Hampstead Garden Suburb
Other services in Hampstead Garden Suburb
Work for landlords, hotels and businesses
For anyone letting property in or around Hampstead Garden Suburb, several properties can go on one quote. Just tell us the addresses and what each one needs.
We also work for businesses, from offices to washrooms and kitchens. On commercial sites, working times can be discussed when we quote.
Your questions about sand mastic in Hampstead Garden Suburb
Can you help a landlord with a rental near Brent Cross West station?
Yes, rental work is part of what we do. You can ring 0345 464 0079 or send us an email with the address and a few details, and we will give you a fixed price before any work starts.
Can you do sand mastic in Hampstead Garden Suburb?
Yes, Hampstead Garden Suburb is within the area we cover. We work across London and the South East. Just call 0345 464 0079 or drop us an email with a few details of the job, and we will send you a clear quote.
Is it messy?
Not at all. The area is protected while we work and cleaned up afterwards.
Is it OK to seal over old sealant?
No, and we never do. It can look neat for a few weeks, but the new layer lifts away from the old one. Removing the old sealant completely is the only lasting way.
What is sand mastic?
It’s a mix of sand and a linseed-oil-based binder. It’s applied by hand and finished to sit neatly against the masonry.
What do you put in the joint?
It depends on the joint: sanitary silicone where it gets wet, and sealants suited to movement or weather elsewhere. Brands we use include Arbo and Everbuild.
Do you guarantee sand mastic work?
Every job comes with our one-year guarantee, and we’re fully insured.
Can you quote for more than one area?
Yes, and it often makes sense. Doing several areas at once is usually more efficient, so mention them when you ask for a quote.