Oxfordshire · England
Kingston Stert External Mastic
Sealing brickwork movement joints, render, cladding and façade joints for homeowners, landlords and businesses in Kingston Stert. Fully insured, ARBOMaster approved and guaranteed for a year.
- Leaking joints around cladding and façade panels
- Joints where the bead has come unstuck
- Old sealant gone brittle and cracked
External mastic in Kingston Stert
A movement joint is a deliberate break that lets a wall expand and contract. The sealant in it has to stretch and squeeze for years, so once it splits or hardens, the joint stops working and water gets in. Typical jobs include movement joints filled with mortar instead of sealant and failed seals between different materials, across render & cladding joints, concrete & block and joints between brick and frames.
In a village or hamlet like Kingston Stert, older cottages and farm buildings often stand in the open, where walls and rooflines take the weather head on. Gutter joints and wall joints there need a sealant that can flex and stay put.
Whatever the size of the job, you get the same one-year guarantee in Kingston Stert and across Oxfordshire.
- Location
- Kingston Stert (OX39)
- Region
- Oxfordshire
- Guarantee
- A year, on every job
- Price
- A clear price before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
How to look after the new joints
Joint life depends on how it’s used and looked after. Here’s what we suggest:
- Do not let climbing plants root in the sealant
- Avoid pressure-washing directly into sealant joints
- Fix overflowing gutters above sealed joints
- Point out the joints to other trades
Follow the cure time we give you before the joint is knocked or disturbed. The surface skins over quickly, but full cure takes longer.
Small splits are the time to act. Then it’s a straightforward cut-out and reseal before water has had years to get in.
Why deal with it now?
Resealing a run of joints in one go is generally better than patching one at a time. Joints of the same age tend to fail together. Around Kingston Stert, older homes often have timber in their floors and frames, and water through a failed joint can rot timber if it’s left.
Every job is a little different, so we quote each one individually. Size, access and the product the joint needs all make a difference, and we’ll explain the quote if you ask.
Why us?
- Colour picked to suit the job
- Rated 4.9 stars on Google
- Tidy, careful work
- Colour agreed with you before work begins
Read what affects the cost and our reviews.
Different surfaces, different methods
Copings and trims
A failed coping joint lets water into the top of the wall. Resealing them is a small job that protects a lot.
Cladding and façade panels
Panel systems often rely on sealant between and around the panels. Each joint gets a sealant that suits the panel and its movement.
DIY sealant or a professional job?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
More services for Kingston Stert
Questions from Kingston Stert
Will you come out to Kingston Stert?
Yes, we do. Our work covers London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
Can you do external mastic in Kingston Stert?
Yes, Kingston Stert is within the area we cover. Our work covers London and the South East. You can phone 0345 464 0079 or send us an email and let us know what needs doing.
Can new sealant go over the old?
No. New silicone won’t bond to old silicone, and it traps any mould or water underneath. We remove it all first.
Does someone need to be in?
It depends on the job. For work indoors, someone needs to let us in, while outside work can sometimes be arranged differently.
Can a movement joint be filled with mortar?
No. Cement or mortar cannot stretch and the joint fails. Where a joint has been mortared, it can often be raked out and sealed properly.
Can you quote for more than one area?
Yes. More than one area can go on one quote.
Do you hold any approvals?
Yes. We are approved under the ARBOMaster scheme, the approved applicator scheme for Arbo sealants.
Do the sealants smell?
Sometimes, a little. It fades as the sealant cures, and ventilation helps.
Walls and rooflines in Kingston Stert
Historic houses like Adwell House (about 2.1 miles south-west) are a reminder that the area around Kingston Stert has older buildings as well as new. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth. London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Homes close to Church of St Mary include some older properties, and old and new materials meet at the roofline and walls, which is where sealant earns its keep. Managing a site like Aston Rowant Church of England Primary School? Then movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
Kingston Stert is about 3 miles south of Thame, in Oxfordshire. If you need external mastic in Kingston Stert, it’s easy to get a quote: please phone 0345 464 0079 or send us an email. We’re based in Crawley and cover Oxfordshire. Our area takes in 443 places across Oxfordshire, from the larger towns to small villages. We also work in Oxford, about 13 miles from Kingston Stert.
Postcode districts we cover here for external mastic: OX39. Nearby, we also carry out external mastic in Sydenham (1 mile north-east), Emmington (1 mile north-east), Chinnor (2 miles east), Towersey (3 miles north) and Thame (3 miles north). Within a short drive, we also cover Oxford (13 miles west), Didcot (14 miles south-west), Abingdon-on-Thames (14 miles west), Henley-on-Thames (12 miles south), Benson (9 miles south-west) and Headington Quarry (11 miles west).
What’s near Kingston Stert
Locally, jobs take us to homes and businesses close to The Crown Inn. Kingston Stert’s nearest station is Princes Risborough station, about 4.6 miles east. Well-known places in the area include Thame Museum (3.5 miles north-west) and Thame Community Hospital (3 miles north). For a walk, there’s Bald Hill and Oakley Hill nature reserve.
Landlords, agents and businesses in Kingston Stert
In hotels, rooms out of use cost money, so we plan the work room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
We also work for property managers and facilities teams. We can quote a run of properties together, and we are fully insured for the work.
Signs you need external mastic in Kingston Stert
Sometimes a movement joint was filled with mortar or a rigid filler. The joint cannot move, so the wall cracks somewhere else instead.
The most common problems we see are:
- Old sealant gone brittle and cracked
- Sealant pulling away from one side of the joint
- Movement joints with cracked, split or missing sealant
- Gaps where render, brick and frames meet
If you let a flat or house near Princes Risborough station, split movement joints are easy to miss on a rental until damp shows inside.
What your quote should include
- What happens if they find a problem under the old sealant
- Whether all the old sealant comes out first
- How much experience the applicator has
- What guarantee comes with the work
What happens on the day
Before we leave, we go over the finished joints with you and explain the cure time. The visit itself usually takes a few hours for a handful of joints, longer for a whole elevation, depending on the size of the job. In a small place like Kingston Stert, access is usually the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- We start by checking each joint, agreeing the ones to redo and how we’ll reach them.
- The old mastic and anything lodged in the joint is removed.
- The joint faces are cleaned and primed where the sealant needs it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- We gun in a flexible exterior sealant in a colour that suits the wall and tool it neatly.
Getting ready for the visit
- Plan for the work area to be out of bounds to pets and children
- For indoor joints, keep the area dry beforehand if you can
- Tell us about any water getting in
Ask for a quote
For a quote, ring 0345 464 0079 or send us an email and tell us where the job is and what the problem looks like. We’ll send you a clear quote before any work starts.