Kent · England
Sand mastic for sash & case windows in Sepham Heath, Kent
Problem with your window and door surrounds in Sepham Heath? We cut out the old, prepare the joints and apply the right sealant.
- Failed mastic on an exposed elevation
- Open joints round the window box
- Wind and rain getting in round a sash window
What the job involves on each surface
Period and listed homes
Period homes look their best with traditional materials, and sand mastic is one of them.
Stone surrounds
Stone surrounds suit sand mastic well. It finishes to look like part of the surround.
Sand mastic in Sepham Heath, done properly
We renew sand mastic around sash windows and doors in stone and brick. Out comes the old, loose mastic, and new mastic is applied and shaped by hand. If you’re dealing with failed mastic on an exposed elevation and old sand mastic that has cracked, crumbled or fallen out, we can help.
Outdoor sealant needs dry, clean surfaces, so work on frames around Sepham Heath is planned for dry weather. Let us know about access to all the frames, upstairs ones included.
All of our work is guaranteed for twelve months, in Sepham Heath and everywhere else we cover.
- Where
- Sepham Heath (TN14)
- Region
- Kent
- Guarantee
- One year on every job
- Quote
- Quoted before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
For landlords and businesses
In hotels, rooms out of use cost money, so we plan the work room by room. Hotel work is part of what we do, alongside homes and businesses.
We also work for property managers and facilities teams. Several sites can go on one quote, and we are fully insured for the work.
Honest limits
To be straight with you, there are a few things sealant will not fix:
- Decayed frames that need repair
- Planning or listed building consent (your local planning authority decides)
- Damaged stone surrounds
If you’re not sure, just phone 0345 464 0079 or send us an email and we’ll give you a straight answer before booking.
Joints and surfaces we work on
- Tenement windows
- Period & listed homes
- Timber door frames
- Sash and case windows
- Brick reveals
- Stone surrounds
Quotes for sand mastic in Sepham Heath
Some jobs are bigger than they look, and some smaller. What affects the quote:
- Working hours on commercial sites
- How easy the joints are to reach
- The type of sealant required
- The size of the job
Combining jobs into one visit is normally more efficient than separate visits, so it’s worth mentioning everything you’d like done. We will give you a clear quote for the lot.
Helping us quote
Photos by email are helpful but not essential. Try to tell us:
- The rough size of the job
- Any previous sealing or DIY work
- A few pictures by email, if you can
- Access, such as stairs, a lift or height
Want a quote for sand mastic? Please call 0345 464 0079 or send us an email and tell us about the job. We will explain what we’d do and give you a clear price before any work starts.
Also near Sepham Heath
What else we do in Sepham Heath
What happens if it’s left?
New mastic over crumbling mastic will not hold. Raking out and preparing the joint gives it a sound base so the new mastic stays put. Older cottages and farmhouses around Sepham Heath can have timber floors and frames, where water from a failed joint can cause rot if it’s left.
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. You will know the price before we begin.
Why choose Mr Mastic in Sepham Heath
- Fully insured
- An ARBOMaster approved applicator
- Homes, businesses and hotels
- We never seal over old sealant
Read how sealant jobs are priced and customer reviews.
Sepham Heath questions
Do you work for landlords with property near Knockholt station?
Yes, landlords and agents are among the people we work for. You can ring 0345 464 0079 or email us with the details for a clear quote.
Will you come out to Sepham Heath?
Yes, Sepham Heath is covered. Our work covers London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
How long does sand mastic take to harden?
It takes a while. The skin forms first, and the full set comes later and we will give you an idea for your job.
How do I get a quote for sand mastic in Sepham Heath?
We do not publish prices, because the cost depends on the job: how much there is, what’s there now, how we reach it and what it needs. You will get a clear quote before work begins.
Can you replace silicone on a period window with sand mastic?
In most cases. We remove the silicone and clean the joint, then point it with sand mastic.
Can you do several jobs on one visit?
Yes, we can. More than one area can be quoted together.
Can sand mastic be painted?
It’s traditionally left unpainted, as guidance on traditional windows advises. Ask us before decorating.
What should I tell you?
Tell us what needs doing and where, plus pictures if you have them. If we need more, we’ll ask.
What sand mastic looks like in Sepham Heath
The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Historic houses like Lullingstone Castle (about 3.1 miles north-east) are a reminder that the area around Sepham Heath has older buildings as well as new. 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.
In the older streets around Otford Lane Mission Church, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. If you look after a building such as Halstead Community Primary School, its window and door frames need their mastic kept sound, just like a home’s.
Sepham Heath is about 3 miles north-west of Sevenoaks, in Kent. We carry out sand mastic for homeowners, landlords and businesses in Sepham Heath and nearby, as part of our work across Kent. Our area takes in 922 places across Kent, from the larger towns to small villages. There’s also a page for London, roughly 16 miles from Sepham Heath.
Here we cover the TN14 postcode area for sand mastic. We also cover the places around Sepham Heath: Halstead (1 mile north-west), Twitton (1 mile south-east), Badgers Mount (1 mile north), Knockholt Pound (1 mile south-west) and Shoreham (1 mile north-east). Further out, we also cover Dartford (9 miles north), Sevenoaks (3 miles south-east), Royal Tunbridge Wells (14 miles south), Gravesend (12 miles north-east), Tonbridge (10 miles south-east) and Northfleet (11 miles north-east).
Around Sepham Heath
Locally, jobs take us to homes and businesses close to Crown Cottages The Rose And Crown Public House and Polhill Bank and the streets around them. For rail, the closest station is Knockholt station, roughly 1.7 miles north-west of the centre. Other landmarks nearby include Lullingstone Castle (3.1 miles north-east) and Sevenoaks Hospital (3.1 miles south-east). Not far away are Betsom's Hill and Dryhill Nature Reserve.
What happens on the day
Our applicators work methodically: protect, prepare, seal, tidy. Typically it takes a few hours per window, depending on the condition of the joints, and the area is left clean. Somewhere as small as Sepham Heath, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- Each surround is checked first.
- We rake out the old mastic and clean the joint.
- Large voids are packed out.
- We point the joint with sand mastic by hand.
- We finish the mastic to a tidy line.
Preparing for the visit
- On commercial sites, let us know about site rules
- Move anything stored near the joints
- Plan for the work area to be out of bounds to pets and children
Getting a quote
There’s no standard price list. Instead, we send you a clear quote for your job. To arrange one, ring 0345 464 0079 or email us.
Advice
What we’re called out for in Sepham Heath
Timber swells and shrinks with the weather. That movement opens up the mastic joint little by little.
Any of these means the joints need attention:
- Draughts and rain around sash boxes
- Gaps between timber frames and stone or brick
- Crumbling sand mastic round a window
- Weathered mastic on the most exposed windows
Letting a property close to Knockholt station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about.
Before you book anyone
- Is VAT in the price?
- Whether they seal over old material or remove it
- How hidden problems are handled
- Which colour the sealant will be