Kent · England
Sand mastic for sash & case windows in Cold Harbour, Kent
Window and door surrounds in Cold Harbour need attention? We cut out the old, prepare the joints and apply the right sealant.
- Gaps where the frame meets the masonry
- Old sand mastic that has cracked, crumbled or fallen out
- Mastic worn away on windows facing the weather
Sand mastic in Cold Harbour, done properly
Fresh sand mastic forms a skin quite soon, but it takes longer to harden fully. Traditionally, sand mastic is left unpainted, so ask us before you decorate. We work on sash and case windows, stone surrounds and tenement windows, and the jobs we see most are wind and rain getting in round a sash window and mastic that needs renewing before redecorating.
Somewhere as small as Cold Harbour, 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.
Your job is guaranteed for a year, as with all our work.
- Location
- Cold Harbour (ME17)
- Wider area
- Kent
- Cover
- One year on every job
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Common problems we fix in Cold Harbour
Over the years, sand mastic weathers. It hardens, cracks and starts to come away on the stone or timber.
Keep an eye out for any of the following:
- Gaps where the frame meets the masonry
- Cement or filler used on old window joints that has cracked
- Mastic dropping out of the joint
- Failed mastic on an exposed elevation
If you let a flat or house near Charing station, older sash windows in a rental need their mastic kept sound to keep the weather out.
Questions to ask before you book
- Are they insured?
- How hidden problems are handled
- What product goes in the joint
- What the cure time is
Different surfaces, different methods
Timber door frames
A neat sand mastic joint round a front door suits a period home.
Stone surrounds
Sand mastic sits naturally against stone. The finish blends with the masonry.
What happens on the day
When we arrive, we look over the joints with you first. We protect the surfaces around the joints before any work begins. The work normally takes a few hours for a single window, longer for several. Somewhere like Cold Harbour needs a little journey planning: let us know about lanes, gates and parking. We bring what the job needs, so it can be finished in one trip where possible.
- We start by checking each surround and agreeing the joints to renew.
- The loose and crumbling mastic is raked out and the joint cleaned.
- We pack any deep gaps so the mastic sits at the right depth.
- The mastic is mixed, pressed into the joint by hand and shaped.
- We dress the surface so it sits neatly against the masonry.
Before we arrive
- Let us know if you’ve seen damp or leaks
- Mention any parking rules near the property
- Where the joints are inside, avoid wetting them before we arrive
Get a quote
We quote each job on its own. Just call 0345 464 0079 or drop us an email with the details and send pictures if you have them.
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Nearby places to Cold Harbour
Other services in Cold Harbour
Landlord and commercial work in Cold Harbour
We work for landlords and letting agents as well as homeowners. Sealant work between tenants is a simple way to keep a property in good order before the next move-in.
Letting agents often deal with us directly. Tell us the address, the job and how access works and we will give you a quote.
Why deal with it now?
Replacing sash windows is a big decision for a period home and on a listed home, consent may be needed. Where the frames are in good order, new mastic seals the surround. In a small place like Cold Harbour, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
Commercial jobs are quoted on the same basis as homes: how much there is to do, how we reach it and what it needs, plus any working-time requirements on site. Call for a quick quote and we’ll go through it with you.
What you get with us
- More than 20 years in sealant work
- 180+ five-star Google reviews
- Homes, businesses and hotels
- We’re fully insured
Take a look at our cost guide or customer reviews.
What we cannot put right
A few problems are outside what sealant work can do:
- Decisions on consent for listed homes
- Putty and glazing repairs
- Crumbling stone or brickwork round the window
If in doubt, ring 0345 464 0079 or email us and we will say what we think before you book.
What we seal
- Sash and case windows
- Timber door frames
- Period & listed homes
- Brick reveals
- Stone surrounds
- Tenement windows
Common questions in Cold Harbour
I let a flat near Charing station. Can you help?
Yes, rental work is part of what we do. Just ring 0345 464 0079 or drop us an email and tell us about the property, and we will give you a clear price.
Can you do sand mastic in Cold Harbour?
Yes, Cold Harbour is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or email us and tell us what needs doing, and we will send you a clear quote.
Can you seal over the old sealant?
No, it will not last. It can look neat for a few weeks, but the new bead soon lifts. The old sealant has to come out completely.
What’s sand mastic made of?
It’s sand mixed with a linseed-oil-based binder, used between timber frames and stone or brick.
How much does sand mastic cost in Cold Harbour?
Size, access and the old material all affect the cost. Ask us for a quote.
What do you put in the joint?
Products from Arbo and Everbuild, among others, picked for each joint. We explain the product when we quote.
Where do you work from?
We work from Crawley. We cover Cold Harbour and the rest of Kent, along with the rest of our area.
Do you take out the old sealant first?
Yes. We cut out all the old sealant and clean the joint.
Cold Harbour homes and the weather
Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Historic houses like Belmont House and Gardens (about 3.8 miles north-east) are a reminder that the area around Cold Harbour has older buildings as well as new. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window.
For an older house near a landmark such as Church of St Lawrence, the joint between an old wall and a newer frame is usually the first place rain gets in.
Cold Harbour is about 7 miles south-west of Faversham, in Kent. Anywhere in ME17, we cover sand mastic for homes and businesses. Our Kent coverage runs to 922 places, Cold Harbour among them. There’s also a page for Chelmsford, roughly 37 miles from Cold Harbour.
Here we cover the ME17 postcode area for sand mastic. Other places close to Cold Harbour include Warren Street (1 mile north-west), Payden Street (1 mile north-west), Lenham Heath (2 miles south-west), Charing Heath (2 miles south) and Lenham Forstal (2 miles south-west). We also work in nearby towns such as Maidstone (11 miles west), Ashford (8 miles south-east), Canterbury (14 miles east), Sittingbourne (7 miles north), Whitstable (14 miles north-east) and Faversham (7 miles north-east).
Local landmarks in Cold Harbour
Typical jobs here are in homes near The Harrow pub and Spuckles and Kennelling Woods, among other places. Cold Harbour’s nearest station is Charing station, about 2.3 miles south of the centre. Well-known places in the area include Newnham Castle (3.4 miles north).
How we quote for sand mastic
We quote each job individually. This is what makes a difference:
- Working hours on commercial sites
- Which sealant suits the joint
- The number and length of the joints
- The number of rooms or windows
Some things make a job bigger or smaller: how much old sealant there is and how stubborn it is, whether mould needs treating, and whether the work is at height. Your quote takes all of that into account.
What to tell us for a quote
What to tell us when you ask for a quote:
- How we’d reach the joints
- Pictures of the joints, sent by email
- How many joints, rooms or windows are involved
- Where the job is, and your postcode
Need a quote? Please ring 0345 464 0079 or email us and tell us about the job. You will know what we plan to do, and what it will cost, before any work begins.