Kent · England
Sand mastic for sash & case windows in Challock, Kent
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for homes and businesses in Challock and across Kent. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Draughty sash windows at the surround
- Old sand mastic that has cracked, crumbled or fallen out
- Gaps where the frame meets the masonry
How we handle sand mastic in Challock
Sand mastic has long been used to fill the joint between timber frames and masonry. It’s made from sand and a linseed-oil-based binder and built up by hand. On period homes, it looks right where silicone wouldn’t. We work on sash and case windows, stone surrounds and brick reveals, and the jobs we see most are draughty sash windows at the surround and old cement repairs round a window that have failed.
Somewhere as small as Challock, older homes often have timber frames set in stone or brickwork. Not every older frame suits a modern silicone bead, so the sealant has to be chosen to suit the building.
A one-year guarantee comes as standard, so you are not left on your own once the job is done.
- Location
- Challock (TN25)
- Region
- Kent
- Guarantee
- 12 months on all our work
- Price
- A clear price before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Different surfaces, different methods
Timber door frames
Sand mastic is used round timber door frames too. The method is the same as for windows.
Tenement and terrace windows
Upper-floor windows need access planning. Let us know the floor and we’ll confirm access.
What affects the cost of sand mastic
Some jobs are bigger than they look, and some smaller. What affects the quote:
- Whether old sealant or filler has to be cut out
- The amount of work
- The number of rooms or windows
- Any mould that needs treating
Rather than a set price list, we price the job in front of us: how many joints, what’s in them now and how we reach them. The price is agreed before we begin.
What we need to know
To make quoting easier, let us know:
- Whether it’s a home or a business
- Pictures of the joints, sent by email
- The rough size of the job
- If someone has resealed it before
We quote each job on its own, so the first step is telling us about yours. Simply phone 0345 464 0079 or drop us an email and describe the job, and photos are welcome.
What we do, step by step
On the day, we start by going over the job with you. Surfaces next to the work are protected before we start. Most jobs take anything from a few hours to a full day, depending on how many windows. Somewhere like Challock 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.
- 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.
- The surface is finished to suit the stone or brick.
How to prepare
- For business premises, tell us about site rules or sign-in
- Mention any leaks or damp you’ve noticed
- Mention if the joints have been sealed before
Getting a quote
Getting a quote is simple: tell us what needs doing and where and its rough size. Photos by email help us understand the job.
Related advice
Places near Challock
Also in Challock
Common questions in Challock
I let a flat near Wye station. Can you help?
Yes, we work for landlords and letting agents. Just ring 0345 464 0079 or drop us an email and tell us about the property, and we’ll send you a clear quote.
Do you cover Challock for sand mastic?
Yes. We work across London and the South East, and Challock is part of that. Just phone 0345 464 0079 or drop us an email with a few details of the job, and we will give you a clear price.
Can sand mastic be painted?
It’s traditionally left unpainted, as guidance on traditional windows advises. Talk to us before any painting near it.
How long does sand mastic take to harden?
It skins over fairly quickly but takes longer to harden fully. We’ll explain what to expect before we leave.
Are you an approved applicator?
Yes. We’re an ARBOMaster approved applicator, which is run for the Arbo sealant brand.
What exactly is sand mastic?
It’s sand mixed with a linseed-oil-based binder, used between timber frames and stone or brick.
Can I choose the sealant colour?
We’ll suggest a colour to suit the surroundings. The choice depends on the product the joint needs.
How much does sand mastic cost in Challock?
Every job is different, so each one gets its own quote. To get one, phone 0345 464 0079 or send us an email and let us know what needs doing and where.
What we are called out for in Challock
Previous repairs in cement or silicone often trap water or crack away. They do not move with the timber and we normally remove them.
These are the problems we’re asked about most:
- Crumbling sand mastic round a window
- Patchy fillers round a sash window
- A silicone bead on a sash window that spoils the look
- Mastic that needs renewing before redecorating
Schools such as Challock Primary School are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages.
What to look for in a quote
- What guarantee comes with the work
- Whether they’re fully insured
- How much experience the applicator has
- Which sealant they’ll use, and why
Can I do it myself?
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
If you do try it yourself, take your time over the preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
Looking after it afterwards
To keep the joints looking good and working properly:
- Do not paint over the new mastic
- Look over the window mastic once a year
- Keep modern sealant off the mastic
- Avoid heavy scraping on the mastic joint
Look at the mastic when you look over the windows. Small cracks are easier to deal with early.
Good mastic helps keep the frame dry. Once it fails, water can sit against the timber, which can lead to rot.
Work for landlords, hotels and businesses
Mouldy or split sealant often shows up at the end of a tenancy. We can quote for more than one property at once.
If you manage several properties in or around Challock, several properties can go on one quote. Just tell us the addresses and what each one needs.
Frames and glazing around Challock
Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. With historic houses such as Belmont House and Gardens (about 3.9 miles north) nearby, there’s older building stock in the area around Challock 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.
If you live in an older home near Church of St Cosmas and St Damian, the joint between an old wall and a newer frame is normally the first place rain gets in. For landlords with property near Wye station, any sash windows need sound mastic to keep draughts and rain out.
Challock is about 5 miles north of Ashford, in Kent. Homes, rented property, offices and hotels in Challock is covered for sand mastic, old or new, large or small. The work is guaranteed for a year. Challock is one of 922 places in Kent where we work. For nearby work, see our Chelmsford page, about 40 miles away.
Postcode districts we cover here for sand mastic: TN25. Whether your property is on Chapmans Close, Blind Lane and Old Clock House Green or a nearby road, our applicators can take on the job. We also cover the places around Challock: Pested (1 mile north), Paddock (1 mile west), Stocker's Head (3 miles west), Badlesmere (3 miles north) and Throwley Forstal (3 miles north). Larger places within reach include Maidstone (15 miles west), Ashford (5 miles south), Canterbury (10 miles north-east), Sittingbourne (11 miles north-west), Whitstable (11 miles north-east) and Faversham (7 miles north).
What’s near Challock
In Challock, that means homes and buildings near The Chequers pub and The Hayesbrook School and the streets around them. For rail, the closest station is Wye station, roughly 3.3 miles south-east. A little further out are Tower keep castle at Chilham (3.9 miles north-east) and William Harvey Hospital (5.6 miles south).