Kent · England
Sand mastic for sash & case windows in Chalk, Kent
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for homes and businesses in Chalk and across Kent. ARBOMaster approved applicators, fully insured, with a 12-month guarantee.
- Old sand mastic that has cracked, crumbled or fallen out
- Mastic that needs renewing before redecorating
- Weathered mastic on the most exposed windows
About our sand mastic in Chalk
Fresh sand mastic forms a skin quite soon but full hardening takes longer. Traditionally, sand mastic is left unpainted and we’ll advise if you are redecorating. If you are dealing with cement or filler used on old window joints that has cracked and window mastic to renew ahead of painting, we can help, whatever the surface.
Mastic can only go onto a dry, clean joint, so window work in Chalk is booked around the forecast. Tell us about access to every side of the house, including upper-floor windows.
The work is covered for a year after we finish. If there’s a problem with it, please call 0345 464 0079 or drop us an email.
- Location
- Chalk (DA12)
- Wider area
- Kent
- Guarantee
- 12 months on all our work
- Quote
- A clear price before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Keeping the joints in good condition
Simple care keeps the joints in good condition. We recommend:
- Have rotten timber repaired before new mastic goes in
- Ask the planning authority about consent for listed or conservation-area homes
- Make sure water runs off the sill
- Don’t run silicone over sand mastic
Make sure water drains away from the window surround. Constant wetting wears the mastic faster.
Crumbling mastic lets rain into the joint. That water can reach the timber frame and the wall so early renewal protects both.
Common questions in Chalk
Does living near the coast affect sand mastic in Chalk?
Near the coast, wind-driven rain and, nearer the shore, salt air make outside sealant work harder. Choosing the right sealant for the frame and wall, laid at the right depth, helps it last.
Do you cover smaller places like Chalk?
Yes. Chalk is within the area we cover, which takes in towns, villages and rural addresses. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
Do you have insurance?
Yes. We’re fully insured for every job we do.
Should I try DIY first?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. Most DIY failures come from sealing over old material, wet joints or too much sealant.
What do you need from me for a quote?
Just the basics: where it is, what you’ve noticed and how we reach it. Then call 0345 464 0079 or email us.
When will the new mastic be hard?
Not right away. It skins first and hardens fully later, and we will tell you what to expect.
Can tenants book the work?
We’re happy to deal with the tenant, landlord or agent. Just make sure your landlord agrees.
Can new sealant go over the old?
No, because it fails. The old sealant always comes out first.
Places near Chalk
Also in Chalk
What happens on the day
We work through the job in order: protect, prepare, seal, tidy. For most jobs that takes a few hours per window, depending on the condition of the joints, and the area is left clean. Somewhere as small as Chalk, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We start by checking each surround and agreeing the joints to renew.
- The loose and crumbling mastic is raked out and the joint cleaned.
- Deep voids are packed so the mastic is the right thickness.
- We mix the sand mastic and apply it by hand, shaping it to the joint.
- The mastic is finished to sit tidily against the stone or brick.
Getting ready for the visit
- Let us know about parking restrictions
- Move anything stored near the joints
- Mention if the joints have been sealed before
Getting a quote
Getting a quote is simple: let us know the job and the location. Photos by email help us understand the job, and we will come back to you with a quote.
Advice
Sand mastic in Chalk: local notes
Chalk is close to the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. That’s hard on the mastic around older windows and doors, especially on the side facing the sea. 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.
If you live in an older home near Church of St Mary, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. Managing a site like Thamesview School? Then its window and door frames need their mastic kept sound, just like a home’s.
Chalk is about 1 mile east of Gravesend, in Kent. Wherever you are in the DA12 postcode area, we cover sand mastic for homes and businesses. Across Kent, we cover 922 places, Chalk among them. You can also see our page for Chelmsford, about 21 miles away.
Our applicators cover all of the DA12 postcode area for sand mastic. If you need sand mastic at a property on Chalk Road, Castle Lane and Orlick Road or a nearby road, our applicators can take on the job. We also cover the places around Chalk: Upper Ifield (1 mile south), Thong (1 mile south), Shorne (1 mile south-east), Shorne Ridgeway (2 miles south-east) and Higham (2 miles south-east). Within a short drive, we also cover Maidstone (12 miles south-east), Sittingbourne (15 miles south-east), Dartford (8 miles west), Sevenoaks (14 miles south-west), Northfleet (3 miles west) and Swanley (10 miles west).
Local landmarks in Chalk
Locally, jobs take us to homes and businesses close to Shorne Woods Country Park, Westcourt Primary School and St John's Catholic Comprehensive, among other places. Chalk’s nearest station is Gravesend station, roughly 2 miles west of the centre. Other landmarks nearby include Rochester Castle (4.8 miles south-east) and Gravesham Museum (1.9 miles north-west). The countryside around Chalk includes Gad's Hill and Rede Common.
What happens if it’s left?
Gaps round a sash window let in rain and draughts. Left, water can reach the timber and the wall so renewing it early protects the window. Where a wall is exposed, as many are in small places like Chalk, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
Every job is a little different, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all make a difference, and we will explain the quote if you ask.
Why us?
- Old sealant always removed completely
- An ARBOMaster approved applicator
- Anti-fungal sanitary silicone in wet areas
- Full insurance on every job
Read how sealant jobs are priced and our reviews.
Honest limits
New sealant can’t fix everything, and we will tell you before work begins. It will not solve:
- Rotten sashes, sills or window boxes (a joiner’s job)
- Decisions on consent for listed homes
- Broken panes
If in doubt, ring 0345 464 0079 or email us and we will say what we think.
What we seal
- Sash and case windows
- Timber door frames
- Period & listed homes
- Brick reveals
- Stone surrounds
- Tenement windows
Surface by surface
Tenement and terrace windows
Where a building is shared, window work may involve neighbours so it’s worth checking responsibilities.
Brick reveals
An open joint at a brick reveal lets weather in. Renewing the mastic closes it.
Common problems we fix in Chalk
Timber swells and shrinks with the weather. The movement cracks the mastic over time.
The most common problems we see are:
- Tired mastic found when preparing windows for paint
- Weathered mastic on the most exposed windows
- Draughty sash windows at the surround
- Old cement repairs round a window that have failed
If you let a flat or house near Gravesend station, any sash windows need sound mastic to keep draughts and rain out.
What your quote should include
- How much experience the applicator has
- What product goes in the joint
- Is VAT in the price?
- How the joint is cleaned and prepared
Landlords, agents and businesses in Chalk
We work for letting agents and landlords as well as householders. Sealant work between tenants is a simple way to keep a property in good order.
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.