Kent · England
Window & door mastic in Sandhurst, Kent
We cover Sandhurst for mastic around window and door frames, sills and patio doors. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Sealant in the wrong colour for the frame
- Cracked internal joints between frame and plaster
- Mastic that’s falling out in pieces
Window mastic in Sandhurst, done properly
Every window and door frame has a gap around it, and mastic is what closes it. When it cracks, hardens or pulls away, draughts and rain get in. Our applicators cut it out and replace it with a flexible, weatherproof sealant. Typical jobs include gaps left after new windows were fitted and sealant in the wrong colour for the frame, on uPVC windows, aluminium frames and window sills.
Homes in small places like Sandhurst 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.
There’s a 12-month guarantee on every job.
- Location
- Sandhurst (TN18)
- Wider area
- Kent
- Guarantee
- One year on every job
- Quote
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
What sealant work cannot fix
Some problems need a builder, plumber or other trade rather than us:
- Draughts through the window seals rather than the frame
- Damp problems in the wall away from the window
- A failed sealed unit that has misted up
Not sure which it is? You can call 0345 464 0079 or send us an email and we’ll tell you honestly before you book.
Surfaces we seal
- Aluminium frames
- Window sills
- Timber windows & doors
- Patio & French doors
- Composite doors
- uPVC windows
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.
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Keeping joints in good order is simple maintenance that we can handle for you.
What affects the cost of window mastic
Some jobs are bigger than they look, and some smaller. The main factors:
- Whether old sealant or filler has to be cut out
- When we can work, for business premises
- The product the joint needs
- Whether the work is at height
Leaving a failed joint usually makes the job bigger, not smaller, as water and mould keep getting in. If you’re not sure whether it needs doing, phone 0345 464 0079 or send us an email for an honest opinion and a quote.
What we need to know
When you contact us, it’s useful to know:
- The problem you’ve noticed
- Roughly how big the job is
- Where the job is, and your postcode
- The type of property
It all starts with a short chat. Describe the problem, the location and the size of the job, and we’ll explain how we’d tackle it. When it suits you, phone 0345 464 0079 or send us an email.
Aftercare tips
So the new joints stay in good condition:
- Air rooms to keep condensation down around windows
- Don’t paint over the silicone
- Use gentle cleaners on frames and sealant
- Keep drainage slots and sill grooves clear
Wipe the frames with soapy water when you clean the windows, and avoid solvent cleaners on the sealant.
Water gets in quietly when mastic fails. You might not see it until plaster blows or a damp patch appears inside. Catching it early keeps the fix to a reseal.
Nearby places to Sandhurst
Also in Sandhurst
The process
There isn’t much for you to do on the day. Show us the job and we’ll take it from there. The work itself takes most of a day for a typical house, less for a few frames from start to finish. For a village or hamlet like Sandhurst, the journey is planned in advance: tell us about narrow lanes, gates, long drives and where we can park. We bring what the job needs, so it can be finished in one trip where possible.
- Each frame is looked over and we agree which ones need resealing.
- We remove the old mastic and clean the frame edge and wall.
- Deep gaps get closed-cell backing rod to set the depth.
- A flexible exterior sealant is applied in a colour to suit the frame.
- Every joint is tooled smooth and checked before we leave.
Preparing for the visit
- Mention any tricky access
- Mention any parking rules near the property
- Let us know if you’ve seen damp or leaks
Get a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints, and add pictures by email if you can.
Read more
DIY sealant or a professional job?
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and does not move well, and the joint depth matters as much as the finish.
Sandhurst 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 Great Dixter (about 2.4 miles south-east) are a reminder that the area around Sandhurst 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’s traditional sand mastic.
Managing a site like Sandhurst Primary School? Then the mastic around its windows and doors needs looking after like any other building’s. If you live in an older home near Mission Church, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint. For landlords with property near Robertsbridge station, sound mastic around windows and doors keeps out the draughts and damp that tenants notice first.
Sandhurst is about 11 miles north of Hastings, in Kent. We provide window mastic to homes and businesses in Sandhurst and nearby. 922 places in Kent are on our list, from the larger towns to small villages. Crawley is on our list too, around 33 miles away.
Postcode districts we cover here for window mastic: TN18. If you need window mastic at a property on Bodiam Road, Poundfield Road and Queen Street or anywhere close by, our applicators can take on the job. We also cover the places around Sandhurst: Sandhurst Cross (1 mile south-west), Linkhill (1 mile east), Four Throws (2 miles north-west), Little Conghurst (2 miles north-west) and Bodiam (2 miles south-west). Within a short drive, we also cover Ashford (15 miles north-east), Royal Tunbridge Wells (15 miles north-west), Paddock Wood (13 miles north-west), Tenterden (6 miles north-east), Park Wood (15 miles north) and Staplehurst (10 miles north).
Local landmarks in Sandhurst
We work in homes and buildings around Sentido pub. Sandhurst’s nearest station is Robertsbridge station, about 4.9 miles south-west of the centre. A little further out are The C.M Booth Collection (3.5 miles north-east) and Benenden Hospital (4.8 miles north-east).
Why act early in Sandhurst
A quick bead over the top of old mastic looks like an easy fix, but it won’t grip old, dirty sealant. It soon lifts and the leak carries on behind it. The old mastic has to come out. In a small place like Sandhurst, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
Some things make a job bigger or smaller: the old material and how easily it comes out, whether mould needs treating, and whether we need extra access for height. Your quote takes all of that into account.
Why choose Mr Mastic in Sandhurst
- Full insurance on every job
- White, clear, grey or another colour, product permitting
- An ARBOMaster approved applicator
- Domestic, commercial and hotel work
Read our cost guide or what customers say.
Common questions in Sandhurst
Can you help a landlord with a rental near Robertsbridge station?
Yes, landlords and agents are among the people we work for. You can ring 0345 464 0079 or send us an email with the details for a clear quote.
Is Sandhurst within the area you cover?
Yes. Sandhurst is within the area we cover, which takes in towns, villages and rural addresses. We work across London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Which products do you use?
Quality sealants from brands including Arbo and Everbuild, picked for each joint. We explain the product when we quote.
Is the new sealant paintable?
Silicone generally won’t take paint. If you plan to paint, tell us first and we can use a paintable sealant where it suits the joint.
Can you do the inside joint as well?
Yes. Plenty of draughts come through the inside joint as well as the outside, so it can be worth sealing both.
Are you ARBOMaster approved?
Yes. We hold ARBOMaster approved applicator status, and we are fully insured.
How many windows can you do in a day?
A few frames take a few hours, while a whole house takes longer. We confirm the timing with your quote.
What should I tell you?
Where the job is, what the problem is and roughly how big it is. If you can, email a few photos.