Greater London · England
Forty Hill Sand Mastic
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for homes and businesses in Forty Hill and across Greater London. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Patchy fillers round a sash window
- Open joints round the window box
- Crumbling sand mastic round a window
Sand mastic in Forty Hill
Sand mastic doesn’t last for ever and gaps open up round the frame. We rake it out and renew it and tidies the surround. Typical jobs include wind and rain getting in round a sash window and tired mastic found when preparing windows for paint, on brick reveals, period & listed homes and sash and case windows.
London has a lot of flats and conversions, where windows are often on upper floors. Who looks after the outside of the frames can depend on the lease, so check that first.
Every job is covered by a 12-month guarantee, wherever you are in Greater London.
- Location
- Forty Hill (EN1, EN2)
- Region
- Greater London
- Cover
- A year, on every job
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Work for landlords, hotels and businesses
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance that we can handle for you.
Whether it’s one flat or a portfolio, the work is the same standard: the old material taken out, careful preparation and a 12-month guarantee.
Frames and glazing around Forty Hill
With historic houses such as Forty Hall (about 0.3 miles north) nearby, there’s older building stock in the area around Forty Hill as well as newer homes. 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. London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
As a London address, Forty Hill can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. Schools such as Worcesters Primary School are buildings too, and the mastic around its windows and doors needs looking after like any other building’s. For landlords with property near Turkey Street station, older sash windows in a rental need their mastic kept sound to keep the weather out.
Forty Hill is about 1 mile north-east of Enfield, in Greater London. If you need sand mastic in Forty Hill, it’s easy to get a quote: please phone 0345 464 0079 or email us. We’re based in Crawley and cover Greater London, Forty Hill included. 764 places in Greater London are on our list, from the larger towns to small villages. There’s also a page for London, about 12 miles away.
Our applicators cover all of EN1 and EN2 for sand mastic and the streets around it. That includes homes and businesses on Goat Lane, Acacia Road and Willow Road. Close by, we work in Gordon Hill (1 mile west), Clay Hill (1 mile north-west), Bulls Cross (1 mile north), Enfield (1 mile south-west) and Bullsmoor (1 mile north-east). We also work in nearby towns such as London (12 miles south), City of Westminster (11 miles south), Marylebone (11 miles south), Kensington (13 miles south-west), St Pancras (10 miles south) and Shoreditch (10 miles south).
Near you in Forty Hill
We work in homes and buildings around Chace Community School, Hop Poles pub and Russet House School, among other places. Forty Hill’s nearest station is Turkey Street station, about 1 mile north-east of the centre. A little further out are Edmonton Green Shopping Centre (2.9 miles south) and Museum of Enfield (1.2 miles south-west). Open spaces near Forty Hill include Fir and Pond Woods and Pole Hill.
Looking after it afterwards
Once the sealant has cured, a few habits help it last:
- Ask a joiner to look at soft timber first
- Don’t run silicone over sand mastic
- Go gently near the mastic when preparing windows
- Sort the mastic before the decorators arrive
Avoid sealing over the mastic with silicone. If you see a crack, ask us to take a look before trying a quick fix.
Small cracks are a sign the mastic is ageing. It’s easier to renew it before it drops out.
Forty Hill questions
Can you do sand mastic in Forty Hill?
Yes. We work across London and the South East, and Forty Hill is part of that. Just phone 0345 464 0079 or email us with a few details of the job.
Do you work for landlords with property near Turkey Street station?
Yes, we work for letting agents and landlords. You can call 0345 464 0079 or email us with the address and a few details, and we’ll give you a fixed price before any work starts.
Can you seal over the old sealant?
No, because it fails. We remove every bit of old sealant first, so the new sealant bonds properly.
Are you insured?
Yes. We are fully insured for every job we do.
Can you do several jobs on one visit?
Yes. Tell us about everything you’d like done.
How long does sand mastic take to go off?
It forms a skin fairly soon and it hardens fully over a longer time. Timing depends on the weather and the joint.
Do you take out the old sealant first?
Yes. All of the old material is cut out and the joint cleaned before resealing.
Is there any odour?
It depends on the product. Some products have a noticeable smell, others very little, and any smell fades as they cure.
Nearby places to Forty Hill
More services for Forty Hill
How the job changes by surface
Stone surrounds
The stone is treated with care while raking out the old mastic.
Timber door frames
A neat sand mastic joint round a front door suits a period home.
What we do, step by step
Once we’re on site, we compare the joints with what we discussed. If anything is different, we explain it before carrying on. Most jobs then take a few hours per window, depending on the condition of the joints. 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 agree which joints need doing.
- Old mastic and any loose material are raked out.
- Deep gaps are packed so the mastic sits at the right depth.
- The sand mastic is mixed and pressed into the joint by hand.
- We dress the finish so it sits neatly against the masonry.
Getting ready for the visit
- Let us know about earlier repairs to the joints
- Tell us about any water getting in
- Mention any tricky access
Ask for a quote
Want a quote for sand mastic? Please phone 0345 464 0079 or send us an email and tell us about the job. You’ll know what we plan to do, and what it will cost, before any work begins.
Related advice
Why it’s worth doing now in Forty Hill
Before painting the windows, it pays to renew the mastic. Paint over cracked mastic will not stop the gaps and traditional guidance is to leave the new mastic unpainted. Damp from a failed joint spreads quietly in older London brickwork and timber, and once it shows in Forty Hill, the repair is bigger than a sealant job.
What it costs depends on how much there is to do, how hard the old material is to remove and access to the work. We give a clear quote before we start.
Why us?
- We never seal over old sealant
- Over 20 years’ experience
- Experience in homes, commercial sites and hotels
- Arbo and Everbuild products
Take a look at what affects the cost and what customers say.
What affects the quote in Forty Hill
Call for a quick quote. The main things that affect it are:
- Any mould that needs treating
- Working hours on commercial sites
- Access and height
- The size of the job
No two jobs are quite the same, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all play a part.
What we need to know
Photos by email are helpful but not essential. Please mention:
- Roughly how big the job is
- Any access issues, like height or stairs
- Whether it’s a home or a business
- Whether it has been sealed before
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints, and email photos if that’s easy.
When something else is needed
A few problems are outside what sealant work can do:
- Crumbling stone or brickwork round the window
- Whether work needs listed building consent
- Timber that has rotted
Not sure which it is? You can phone 0345 464 0079 or send us an email and we will tell you honestly before you book.
Where we work in Forty Hill
- Sash and case windows
- Period & listed homes
- Brick reveals
- Stone surrounds
- Timber door frames
- Tenement windows