Oxfordshire · England
Sand mastic for sash & case windows in Charndon, Oxfordshire
Sand mastic across Charndon and nearby, with every bit of old sealant taken out first and a one-year guarantee.
- Wind and rain getting in round a sash window
- Patchy fillers round a sash window
- Mastic round period door frames that has failed
What happens on the day
On the day, there’s very little for you to do. Point us to the joints and we will get on with it. The job generally takes anything from a few hours to a full day, depending on how many windows. For a village or hamlet like Charndon, the journey is planned in advance: 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.
- We look at the surrounds with you and agree the joints to renew.
- We remove the old, loose mastic.
- Deep gaps are packed so the mastic sits at the right depth.
- We apply the mastic by hand and shape it.
- We dress the finish so it sits neatly against the masonry.
Before we arrive
- For indoor joints, keep the area dry beforehand if you can
- Mention if the joints have been sealed before
- Mention any tricky access
Get a quote
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is, and email photos if that is easy.
Read more
How we handle sand mastic in Charndon
A silicone bead around a sash window can look out of place and doesn’t suit the building. Sand mastic gives a finish that matches the age of the house, and we can replace one with the other. We’re often asked to deal with gaps round a timber door in stone or brick and gaps where the frame meets the masonry, on stone surrounds, timber door frames and brick reveals.
Outdoor sealant needs dry, clean surfaces, so work on frames around Charndon is planned for dry weather. Tell us about access to every side of the house, including upper-floor windows.
The work is guaranteed for twelve months. If something isn’t right with it in that time, tell us and we will put it right.
- Place
- Charndon (OX27)
- Region
- Oxfordshire
- Guarantee
- 12 months on all our work
- Quote
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Why deal with it now?
Filling over old, loose mastic does not last. Raking out and preparing the joint gives it a sound base so the new mastic stays put. In a small place like Charndon, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
There are no prices on our website, because each job is priced on what it involves. Call for a quick quote.
Why choose Mr Mastic in Charndon
- Any old sealant cut out fully, not covered over
- Full insurance on every job
- Sanitary silicone with an anti-fungal additive in wet areas
- More than 20 years in sealant work
Read what affects the cost and customer reviews.
What we can’t put right
Sealant isn’t the answer to every problem, and we’d rather say so up front. Sealant won’t put right:
- Decayed frames that need repair
- Masonry that needs repairing
- Sash cords, weights and draught-proofing of the sashes
If you are not sure, just ring 0345 464 0079 or send us an email and we will give you a straight answer before booking.
What we seal
- Stone surrounds
- Period & listed homes
- Brick reveals
- Sash and case windows
- Tenement windows
- Timber door frames
Keeping the joints in good condition
No joint lasts for ever, but care makes a real difference. Our tips:
- Do not paint over the new mastic
- Ask the planning authority about consent for listed or conservation-area homes
- Avoid heavy scraping on the mastic joint
- Plan mastic work ahead of painting
Leave the new mastic alone while it firms up. It skins over quickly, but takes longer to harden fully.
Once mastic starts to crumble, rain gets in. That water can reach the timber frame and the wall, so renewing it early is worth it.
Landlord and commercial work in Charndon
We work for landlords and agents as well as homeowners. Sealant work between tenants is a simple way to keep a property in good order.
In hotels, rooms out of use cost money, so the work can be planned room by room around your bookings where we can. We have worked in hotels as well as homes and businesses.
What sand mastic looks like in Charndon
With historic houses such as Claydon House (about 3 miles east) nearby, there’s older building stock in the area around Charndon as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window. 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.
Homes close to Church of St Michael include some older properties, and the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Charndon is about 6 miles east of Bicester, in Oxfordshire. If you need sand mastic in Charndon, it’s easy to get a quote: please call 0345 464 0079 or drop us an email. We’re based in Crawley and cover Oxfordshire, Charndon included. Our area takes in 443 places across Oxfordshire, from the larger towns to small villages. Oxford is on our list too, around 14 miles away.
We work across OX27 for sand mastic and the streets around it. Whether your property is on Main Street, Spencer Gardens and Wootton Green or anywhere close by, we can help. We also cover the places around Charndon: Calvert (1 mile east), Twyford (1 mile north), Poundon (2 miles north-west), Marsh Gibbon (2 miles south-west) and Hillesden (3 miles north). Within a short drive, we also cover Oxford (14 miles south-west), Bicester (6 miles west), Thame (12 miles south), Kidlington (13 miles south-west), Headington Quarry (13 miles south-west) and Bure Park (6 miles west).
Near you in Charndon
Nearby you’ll also find Bicester Community Hospital (5.9 miles west). For a walk, there’s Calvert Jubilee.
Nearby places to Charndon
Other services in Charndon
Do you need sand mastic in Charndon?
Rain on the window surround works into any crack and loosens it further. Exposed elevations generally fail first.
People usually contact us after spotting something like this:
- Tired mastic found when preparing windows for paint
- Modern sealant on a period surround
- Old sand mastic that has cracked, crumbled or fallen out
- Mastic round period door frames that has failed
In and around Charndon, as anywhere, good sand mastic starts with a clean, dry, properly prepared joint.
What your quote should include
- How much experience the applicator has
- What product goes in the joint
- The length of the guarantee
- What happens if the job turns out different
Surface by surface
Sash and case windows
The box of a sash and case window sits in the stone or brick opening. The gap round it is pointed with sand mastic.
Brick reveals
Loose mastic comes out and deep gaps are packed before the new mastic goes in.
Charndon questions
Do you cover smaller places like Charndon?
Yes, Charndon is covered. We work across London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
Is Charndon in your area for sand mastic?
Yes. Our work covers London and the South East, and Charndon is part of that. You can phone 0345 464 0079 or send us an email and tell us what needs doing, and we’ll send you a clear quote.
Which is right for my windows, sand mastic or modern sealant?
We will help you decide. Sand mastic suits many period homes and newer frames suit modern sealant.
Is it messy?
No. We work neatly, protect the area around the joints and tidy up afterwards.
Can you match the sealant colour?
Most of the time, yes. We’ll tell you which colours the right product comes in and agree one before work begins.
Will the old sealant be removed?
Yes. Sealing over the old bead is the commonest cause of early failure, and it’s something we never do.
Where are you based?
Mr Mastic is based in Crawley. We cover Charndon and the rest of Oxfordshire, along with the rest of our area.
Do you have insurance?
Yes. Full insurance covers our work.