Greater London · England
Sand mastic for sash & case windows in Coombe Hill, Greater London
Window and door surrounds in Coombe Hill need attention? We remove the old material, prepare the joints and seal them properly, with a one-year guarantee.
- Mastic dropping out of the joint
- Old cement repairs round a window that have failed
- Gaps where the frame meets the masonry
Sand mastic in Coombe Hill
Our applicators renew the sand mastic around sash and case windows and doors in stone and brick. Out comes the old, loose mastic, and new mastic is applied and shaped by hand. We’re often asked to deal with window mastic to renew ahead of painting and gaps between timber frames and stone or brick, across timber door frames, tenement windows and brick reveals.
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, which is when draughts and damp patches appear in homes in Coombe Hill.
All our work is covered by our 12-month guarantee, wherever you are in Greater London.
- Where
- Coombe Hill (SW15, KT2)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Sand mastic in Coombe Hill: local notes
Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. With historic houses such as Pembroke Lodge (about 1.5 miles north-west) nearby, there’s older building stock in the area around Coombe 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’s traditional sand mastic.
Coombe Hill is in London, so parking needs planning: let us know about parking bays, permits or a driveway. If you look after a building such as Robin Hood Primary School, larger buildings have plenty of frames, and the mastic around each one ages.
Coombe Hill is about 2 miles north-east of Kingston upon Thames, in Greater London. If you need sand mastic in Coombe Hill, it’s easy to get a quote: please phone 0345 464 0079 or drop us an email. We cover Greater London from our Crawley base, Coombe Hill included. 764 places in Greater London are on our list, large and small. London is on our list too, around 9 miles away.
Here we cover the SW15 and KT2 postcode area for sand mastic. If you need sand mastic at a property on Keswick Avenue, Derwent Avenue and Robin Hood Lane or anywhere close by, we can help. Main roads around Coombe Hill include the A308, so getting to you is simple. We also cover Kingston Vale (1 mile east), Putney Vale (1 mile east), Coombe (1 mile south), Norbiton (2 miles south-west) and Motspur Park (2 miles south-east). We also work in nearby towns such as London (9 miles north-east), City of Westminster (7 miles north-east), Marylebone (8 miles north-east), Kensington (5 miles north-east), St Pancras (9 miles north-east) and Shoreditch (10 miles north-east).
Around Coombe Hill
Around Coombe Hill, our work takes us to homes and buildings near Coombe Girls' School, Canbury School and Richmond Park. For rail, the closest station is Norbiton station, about 1.6 miles south-west of the centre. A little further out are Bentall Centre (2.2 miles south-west) and Kingston Hospital (1.4 miles south-west). For a walk, there’s Kingston Hill Road area and Fishpond Wood and Beverley Meads.
Do you need sand mastic in Coombe Hill?
Timber swells and shrinks with the weather. That movement opens up the mastic joint over time.
Signs it’s time to call us include:
- Gaps where the frame meets the masonry
- Wind and rain getting in round a sash window
- Mastic round period door frames that has failed
- Silicone on a period window that looks wrong
Rented homes near Norbiton station change hands often, and cracked sand mastic around sash windows lets in the draughts tenants complain about.
Before booking anyone
- Whether they seal over old material or remove it
- Which sealant they’ll use, and why
- What the quote includes, VAT included or not
- Who turns up on the day
Aftercare tips
Simple care keeps the joints in good condition. We recommend:
- Leave the new mastic unpainted
- Clear gutters so water doesn’t pour onto the windows
- Get any rot dealt with first
- Avoid heavy scraping on the mastic joint
Check the mastic when you check the paintwork. Catching cracks early keeps repairs small.
Gaps round a sash box let in draughts and rain. Left, the gap tends to get bigger.
How the visit works
On the day, there’s very little for you to do. Point us to the joints and we’ll get on with it. The work itself takes anything from a few hours to a full day, depending on how many windows. In a London area like Coombe Hill, the main things to plan are parking and access: let us know about parking, the floor we will be working on and any lift or shared entrance.
- We check each window surround and the condition of the joint.
- We rake out the old mastic and clean the joint.
- We fill deep gaps so the new mastic isn’t too thick.
- New sand mastic is applied and shaped by hand.
- The finish is dressed neatly.
Before we arrive
- Keep children and pets away from the work area
- Mention any leaks or damp you’ve noticed
- Tell us if parking is tricky
How to get a quote
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 add pictures by email if you can.
Advice
How we quote for sand mastic
Some jobs are bigger than they look, and some smaller. What affects the quote:
- The old material and how stubborn it is
- Mould in or behind the old joints
- Working hours on commercial sites
- The product the joint needs
A few things move the cost up or down: how much old sealant there is and how stubborn it is, whether mould needs treating, and whether we need extra access for height. We take all of that into account in your quote.
Helping us quote
Before you ask for a quote, have a think about:
- Where the property is
- Any access issues, like height or stairs
- Pictures of the joints, sent by email
- How many joints, rooms or windows are involved
Call for a quick quote, or email us if that is easier. Tell us about the joints that need doing and we will explain what’s involved.
Should I try it myself first?
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
Questions from Coombe Hill
Do you cover Coombe Hill for sand mastic?
Yes. We work across London and the South East, and Coombe Hill is part of that. Just ring 0345 464 0079 or send us an email with a few details of the job.
Is parking a problem for a job in Coombe Hill?
In much of London, parking needs planning: a visitor permit or a bay close to the door helps a lot.
Do I need permission for sand mastic on a listed building?
Checking first is sensible. Ask your local planning authority whether consent is needed for work on a listed home or in a conservation area.
Will it make a mess?
We keep the work tidy. We protect what’s around the joints, and we clear up when we are done.
Do I need to be at home?
For indoor joints, yes, someone needs to let us in. After that, you can carry on with your day.
What guarantee comes with the work?
There’s a 12-month guarantee on every job, sand mastic included.
Is it OK to seal over old sealant?
No, and we never do. It can look neat for a few weeks, but the new bead soon lifts. The old sealant has to come out completely.
How long does sand mastic take to go off?
Not right away. It skins first and hardens fully later and we will give you an idea for your job.
Surface by surface
Timber door frames
Sand mastic is used round timber door frames too. We renew it the same way as on windows.
Tenement and terrace windows
Where a building is shared, window work may involve neighbours, so check who is responsible first.
What happens if it’s left?
New mastic over crumbling mastic won’t hold. Raking out and preparing the joint gives it a sound base so the new work lasts. In older London homes, water behind a failed joint soaks into brick and timber without much sign, and by the time it shows on a wall or ceiling in Coombe Hill, the repair is bigger than the sealant job would have been.
What it costs depends on the size of the job, how hard the old material is to remove and access to the work. We give a clear quote before we start, so you know where you stand.
What you get with us
- Over 20 years’ experience
- 4.9 on Google from 180+ five-star reviews
- Full insurance on every job
- A 12-month guarantee on all work
Take a look at our cost guide or what customers say.