Greater London · England
Sand mastic for sash & case windows in Brockley Hill, Greater London
We cover Brockley Hill for traditional burnt sand mastic around sash and case windows and doors in stone and brick. Old sealant removed completely, joints prepared properly and a 12-month guarantee.
- Old sand mastic that has cracked, crumbled or fallen out
- Draughts and rain around sash boxes
- Modern sealant on a period surround
Aftercare tips
After the cure time, these simple habits help:
- Don’t paint over the new mastic
- Clear gutters so water doesn’t pour onto the windows
- Inspect the joints round the windows every year or so
- Go gently near the mastic when preparing windows
Avoid painting over the new mastic, as traditional guidance advises. Ask us before any decorating around it.
Crumbling mastic lets rain into the joint. It can soak into the frame and the surrounding masonry so early renewal protects both.
About our sand mastic in Brockley Hill
Traditional burnt sand mastic blends with stone and brick surrounds. It suits period and listed homes where a modern sealant bead would stand out. If you’re dealing with tired mastic found when preparing windows for paint and weathered mastic on the most exposed windows, we can help.
From mansion-block windows to modern glazing in new flats, London has every kind of frame. Over the years, the sealant around them shrinks, cracks and pulls away, letting in draughts and water.
Our work is backed for twelve months.
- Where
- Brockley Hill (HA7, HA8, WD6)
- Wider area
- Greater London
- Cover
- One year on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Nearby places to Brockley Hill
Other services in Brockley Hill
Should I try it myself first?
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
Work for landlords, hotels and businesses
In hotels, rooms out of use cost money, so we plan the work room by room around your bookings where we can. We have worked in hotels as well as homes and businesses.
We also work for property managers and facilities teams in Brockley Hill and across Greater London. Several sites can be quoted together, and we’re fully insured.
Sand mastic in Brockley Hill: local notes
In a converted house or block, who looks after the windows depends on the lease, so check that before booking. With historic houses such as Headstone Manor (about 3.4 miles south-west) nearby, there’s older building stock in the area around Brockley Hill 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.
As a London address, Brockley Hill can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. For site and facilities teams at buildings such as London Academy, larger buildings have plenty of frames, and the mastic around each one ages. Homes close to St Peter include some older properties, and the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Brockley Hill is about 1 mile north of Stanmore, in Greater London. Wherever you are in the HA7 postcode area, our applicators can take on sand mastic. Across Greater London, we cover 764 places, and Brockley Hill is one of them. For nearby work, see our London page (13 miles or so).
Here we cover the HA7, HA8 and WD6 postcode area for sand mastic. If you need sand mastic at a property on Wood Lane, Brockley Avenue and Pipers Green Lane or a nearby road, we can help. We also cover Stanmore (1 mile south), Bushey Heath (2 miles west), Belmont (2 miles south-west), Harrow Weald (2 miles south-west) and Bushey (3 miles north-west). We also work in nearby towns such as London (13 miles south-east), City of Westminster (10 miles south-east), Marylebone (10 miles south-east), Kensington (10 miles south-east), St Pancras (11 miles south-east) and Shoreditch (12 miles south-east).
Around Brockley Hill
In Brockley Hill, that means homes and buildings near Abercorn Arms Public House, Aylward Primary School and Edgwarebury Park and the streets around them. The closest station to Brockley Hill is Elstree & Borehamwood station, about 1.8 miles north-east. Nearby you’ll also find Royal National Orthopaedic Hospital (less than half a mile north-west) and Hilfield Castle (2.2 miles north-west). Open spaces near Brockley Hill include Darland's Lake and Edgware Way Grassland.
Honest limits
We’d rather tell you now than do work that won’t last, so these are the limits:
- Timber that has rotted
- Cracked or broken glass
- Whether work needs listed building consent
Not sure which it is? You can ring 0345 464 0079 or drop us an email and we will tell you honestly.
Joints and surfaces we work on
- Timber door frames
- Brick reveals
- Sash and case windows
- Stone surrounds
- Period & listed homes
- Tenement windows
Your questions about sand mastic in Brockley Hill
Can parking be tricky for a visit in Brockley Hill?
In much of London, parking needs planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
Can you do sand mastic in Brockley Hill?
Yes, Brockley Hill is within the area we cover. We work across London and the South East. You can call 0345 464 0079 or email us and let us know what needs doing.
Should I check with the council before work on a listed or conservation-area home?
Checking first is sensible. Your local planning authority can say if consent is needed for listed or conservation-area properties.
Can I do it myself?
You can, for simple jobs. Preparation is everything: all the old sealant out, and a clean, dry joint. We can always put it right if it fails.
How long does the job take?
Typically it takes anything from a few hours to a full day, depending on how many windows. Larger jobs naturally take longer, and we will tell you how long to expect.
Can sand mastic be painted?
It’s traditionally left unpainted, which is what traditional guidance recommends. Talk to us before any painting near it.
Is it OK to seal over old sealant?
No. New silicone won’t bond to old silicone, and anything trapped underneath, including mould and water, stays there. It all has to come out first.
Do you work for hotels and businesses?
Yes. We work in offices, washrooms, hotels and other commercial premises. Working times can be discussed when we quote.
How the visit works
Every visit runs the same way: we look at the joints together, protect the area around them, carry out the job and clear up. It normally takes anything from a few hours to a full day, depending on how many windows. In a London area like Brockley Hill, the main things to plan are parking and access: tell us about permits, visitor bays or off-street space, which floor we are working on and whether there’s a lift.
- We check each window surround and the condition of the joint.
- The joint is raked out and cleaned.
- We fill deep gaps so the new mastic is not too thick.
- We point the joint with sand mastic by hand.
- The finish is dressed neatly.
Before we arrive
- Tell us about any water getting in
- Tell us about access, such as stairs, a lift or high-level joints
- Move anything stored near the joints
Getting a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints, and add photos by email if you can.
Related advice
What the job involves on each surface
Brick reveals
An open joint at a brick reveal lets weather in. Renewing the mastic closes it.
Period and listed homes
On a listed home or in a conservation area, the right material matters. Like-for-like sand mastic is generally favoured.
How we quote for sand mastic
The quote reflects the job in front of us. We take into account:
- Whether the work is at height
- Mould in or behind the old joints
- The size of the job
- Whether old sealant or filler has to be cut out
Some things make a job bigger or smaller: the old material and how easily it comes out, whether mould needs treating, and whether the work is at height. We take all of that into account in your quote.
What we need to know
When you call or email, it’s useful to know:
- Access, such as stairs, a lift or height
- The problem you’ve noticed
- Roughly how big the job is
- The address or postcode of the job
There’s no standard price list. Instead, your job gets its own clear quote. To arrange one, phone 0345 464 0079 or send us an email.