Kent · England
Sand mastic for sash & case windows in Hartley, Kent
Problem with your window and door surrounds in Hartley? We cut out the old, prepare the joints and apply the right sealant.
- Mastic round period door frames that has failed
- Cement or filler used on old window joints that has cracked
- Window mastic to renew ahead of painting
Do you need sand mastic in Hartley?
Some old mastic was never deep enough. Mastic that’s too thin cracks and drops out so we make sure the new mastic is the right thickness.
Any of these means the joints need attention:
- Gaps where the frame meets the masonry
- Crumbling sand mastic round a window
- Failed mastic on an exposed elevation
- Mastic that needs renewing before redecorating
Historic houses such as Scotney Castle, about 4.4 miles west, show how far back building around Hartley goes.
Before you book anyone
- How the surfaces are prepared before sealing
- Which colour the sealant will be
- How long to leave it before use
- Which sealant they’ll use, and why
About our sand mastic in Hartley
Sand mastic has long been used to fill the joint between timber frames and masonry. It’s a mix of sand and a linseed-oil-based binder, applied by hand. On period homes, it looks right where silicone wouldn’t. Common call-outs are for mastic worn away on windows facing the weather and a silicone bead on a sash window that spoils the look, across period & listed homes, tenement windows and stone surrounds.
Homes in small places like Hartley often stand in the open, with little to shelter their windows from wind and rain. Exposed frames and sills lose their mastic sooner than sheltered ones.
The work is guaranteed for twelve months. If there’s a problem with our work within the year, let us know and we will sort it.
- Where
- Hartley (TN17)
- Wider area
- Kent
- Cover
- One year on every job
- Quotes
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Other services in Hartley
Honest limits
We won’t take on work that won’t last, so these are the limits:
- Decisions on consent for listed homes
- Sash cords, weights and draught-proofing of the sashes
- Broken panes
If in doubt, call 0345 464 0079 or send us an email and we’ll say what we think.
What we seal
- Period & listed homes
- Stone surrounds
- Tenement windows
- Sash and case windows
- Timber door frames
- Brick reveals
Work for landlords, hotels and businesses
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.
What happens if it’s left?
Silicone might seem the quicker option, but on period stone or brick it often looks out of place. Sand mastic is the traditional material and blends with the stone or brick. In a small place like Hartley, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
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 the work is at height. We take all of that into account in your quote.
Why Hartley clients choose us
- A 12-month guarantee on all work
- Approved under the ARBOMaster scheme
- Trusted Arbo and Everbuild sealants
- Neat joints and a tidy finish
Hartley questions
Will you come out to Hartley?
Yes, we do. We work across London and the South East, from towns to the smallest places. The journey is planned ahead, so it helps to know about access.
Is sand mastic in Hartley guaranteed?
All our work, in Hartley and everywhere else, comes with a 12-month guarantee. We’re also fully insured and ARBOMaster approved.
How do I get a quote for sand mastic in Hartley?
We do not publish prices, because the cost depends on the job: its size, the old material, access and the product needed. You’ll get a clear quote before any work starts.
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.
How long does sand mastic take to go off?
A skin forms quite soon, but full hardening takes longer. We will tell you what to expect for your job.
Should I check with the council before work on a listed or conservation-area home?
Check with your local planning authority. They’ll tell you if consent is needed for work to your windows.
Will you leave a mess?
Very little: the area around the joints is protected first, and we clear up the old sealant and our materials before we leave.
Can tenants book the work?
Yes, but check with your landlord or agent first. Many landlords are glad to have it sorted.
Surface by surface
Timber door frames
Doors face weather and wear and the mastic can crack early. It’s renewed by hand.
Brick reveals
Loose mastic comes out and deep gaps are packed before pointing.
Keeping the joints in good condition
How long the joints last depends on use and care. We suggest:
- Ask the planning authority about consent for listed or conservation-area homes
- Inspect the joints round the windows every year or so
- Avoid heavy scraping on the mastic joint
- Avoid patching sand mastic with silicone
Avoid painting over the new mastic, as traditional guidance advises. If you’re redecorating, ask us first.
An open joint round the box lets weather through. The longer it’s left, the more the joint opens as more mastic falls out.
Sand mastic in Hartley: local notes
With historic houses such as Scotney Castle (about 4.4 miles west) nearby, there’s older building stock in the area around Hartley 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. The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Schools such as High Weald Academy are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages.
Hartley is about 8 miles south-east of Paddock Wood, in Kent. If you need sand mastic in Hartley, it’s easy to get a quote: please call 0345 464 0079 or email us. We cover Kent from our Crawley base. Across Kent, we cover 922 places, Hartley among them. For nearby work, see our Crawley page (30 miles or so).
Here we cover the TN17 postcode area for sand mastic. Whether your property is on Hartley Road, Campion Crescent and Hartley Court Gardens or anywhere close by, our applicators can take on the job. We also cover Swattenden (1 mile east), Cranbrook (1 mile north-east), Baker's Cross (2 miles north-east), Gill's Green (2 miles south) and Beal's Green (2 miles south). Larger places within reach include Maidstone (13 miles north), Royal Tunbridge Wells (11 miles west), Tonbridge (13 miles north-west), Kings Hill (14 miles north), Foley Park (14 miles north) and Paddock Wood (8 miles north-west).
What’s near Hartley
Typical jobs here are in homes near Crane Valley and the streets around them. A little further out are Benenden Hospital (4.7 miles east) and Sissinghurst Castle (3.8 miles north-east).
The process
You don’t need to clear the whole room or building before we come, only the area right around the joints. Everything nearby is protected, and the job takes a few hours for a single window, longer for several for a typical job. Somewhere like Hartley needs a little journey planning: tell us about narrow lanes, gates, long drives and where we can park. Everything for the job comes with us, so a second trip is avoided where possible.
- We look at the surrounds with you and agree the joints to renew.
- We remove the old, loose mastic.
- We pack any deep voids first.
- We apply the mastic by hand and shape it.
- The surface is finished to suit the stone or brick.
Preparing for the visit
- Tell us if parking is tricky
- Mention if the joints have been sealed before
- Mention any sign-in or site rules at work premises
Getting a quote
Asking for a quote is easy: let us know what needs doing and where. Photos by email help us understand the job.