Oxfordshire · England
Sarsden External Mastic
Problem with your movement joints in Sarsden? We remove the old material, prepare the joints and seal them properly, with a 12-month guarantee.
- Failed sealant between panels on a façade
- Rigid filler in a joint that should flex
- Cracked joints where brick meets render or frames
DIY versus a professional finish
Sealing over old silicone is the commonest DIY error. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
External mastic in Sarsden, done properly
Getting the depth right is half the job. Closed-cell backing rod sets the depth and stops the sealant sticking to the back, so it bonds to the two sides only and can stretch. Typical jobs include water getting into walls through failed joints and failed sealant between panels on a façade, across joints between brick and frames, copings & trims and concrete & block.
Somewhere as small as Sarsden, homes and farm buildings often face open ground, where walls and rooflines take the weather head on. Joints on those walls need a sealant that moves with the building and stays in place.
All of our work is guaranteed for twelve months, and the guarantee is the same wherever you are.
- Location
- Sarsden (OX7)
- Region
- Oxfordshire
- Cover
- A year, on every job
- Quotes
- A clear price before work begins
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Places near Sarsden
Other services in Sarsden
What happens on the day
Once we’re on site, we check the joints match what you told us. If anything is different, we explain it before carrying on. Most jobs then take anything from a few hours to several days, depending on the building. For a village or hamlet like Sarsden, 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.
- Each joint is checked and the colour of the new sealant agreed.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- Primer is applied wherever the sealant needs it.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Getting ready for the visit
- Mention if the joints have been sealed before
- Let us know if you’ve seen damp or leaks
- For business premises, tell us about site rules or sign-in
How to get a quote
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is, and we will talk you through what we’d do. When it suits you, ring 0345 464 0079 or email us.
Advice
Questions from Sarsden
Is Sarsden in your area for external mastic?
Yes, Sarsden is within the area we cover. We work across London and the South East. Just ring 0345 464 0079 or send us an email with a few details of the job, and we’ll send you a clear quote.
Is Sarsden within the area you cover?
Yes. Sarsden is within the area we cover, which takes in towns, villages and rural addresses. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Is there a guarantee?
Yes. All our work carries a 12-month guarantee.
Why do you put foam in the joint first?
Backing rod goes into deeper joints as a matter of course. It sets the sealant depth and prevents three-sided bonding, so the joint can move.
Can I do it myself?
It depends on the job. High-level, external movement and fire-rated joints are professional jobs, while a short indoor joint may be within reach.
Can landlords and businesses book you?
Yes, we do. We work in homes, commercial premises and hotels, and we’re fully insured.
Are you fully insured?
Yes. Mr Mastic is fully insured.
Do you seal joints where cladding meets other materials?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. We pick a colour that works with both materials.
Honest limits
We won’t take on work that won’t last, so these are the limits:
- Rising or penetrating damp from elsewhere in the wall
- Adding movement joints to masonry that has none
- Movement that’s more than a sealant joint can take
Not sure which it is? You can ring 0345 464 0079 or drop us an email and we’ll tell you honestly.
Joints and surfaces we work on
- Façade panels
- Brickwork movement joints
- Concrete & block
- Copings & trims
- Render & cladding joints
- Joints between brick and frames
What the job involves on each surface
Concrete and blockwork
Concrete and block walls shrink as they dry and move with temperature. Their movement joints are sealed over backing rod with a flexible sealant.
Render joints
Render has movement joints and stop beads that need sealing. We reseal them with a flexible exterior sealant that suits the render colour.
What affects the cost of external mastic
Some jobs are bigger than they look, and some smaller. The main factors:
- How many rooms, windows or areas are involved
- The product the joint needs
- Whether the work is at height
- Whether there’s mould to deal with
What you pay reflects the work, not a rough estimate. That is why we ask about the job first.
What we need to know
When you contact us, it’s useful to know:
- Whether it has been sealed before
- If it’s domestic, commercial or a hotel
- The problem you’ve noticed
- Where the property is
For a quick quote, get us on the phone, or send an email if you’d rather. Describe what needs sealing and we will talk you through the work.
External mastic in Sarsden: local notes
With historic houses such as Chastleton House (about 4.3 miles north-west) nearby, there’s older building stock in the area around Sarsden as well as newer homes. Where a home is older, 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, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Schools such as Chipping Norton School are buildings too, and its movement joints, gutters and trims need looking after like any other building’s. For landlords with property near Kingham station, failed wall and movement joints let damp in, so they’re worth checking between tenancies. Homes close to Church of St James include some older properties, and older walls, gutters and the joints where extensions meet them need a flexible sealant.
Sarsden is about 9 miles north-west of Witney, in Oxfordshire. For external mastic in and around Sarsden, please phone 0345 464 0079 or send us an email for a quick quote. We cover Oxfordshire from our Crawley base. Across Oxfordshire, we cover 443 places, and Sarsden is one of them. You can also see our page for Oxford, roughly 18 miles from Sarsden.
We work across OX7 for external mastic. If you’re just outside Sarsden, we cover Churchill (1 mile north-west), Chipping Norton (3 miles north-east), Salford (3 miles north), Over Norton (3 miles north-east) and Great Rollright (5 miles north-east). Within a short drive, we also cover Banbury (15 miles north-east), Witney (9 miles south-east), Carterton (10 miles south), Kidlington (14 miles south-east), Neithrop (14 miles north-east) and Grimsbury (15 miles north-east).
What’s near Sarsden
Locally, jobs take us to homes and businesses close to The Chequers pub and the streets around them. The closest station to Sarsden is Kingham station, about 2.2 miles west. Other landmarks nearby include Chipping Norton Museum (2.6 miles north-east) and Wheelbarrow Castle (4.9 miles north).
Keeping the joints in good condition
A little care helps the new joints last. We recommend:
- Keep soil, plants and ivy away from the joints
- Deal with leaking gutters that soak the joints below
- Make sure movement joints aren’t pointed over
- Have failed joints looked at early
If you have more work done on the wall, such as new render, cladding or an opening, show the contractor the movement joints. They should be kept open and resealed, not filled.
A joint that has stopped moving pushes the movement elsewhere, often as cracks near the joint. Resealing it early helps prevent that.
Why act early in Sarsden
Sealing over the top of old mastic does not hold for long. New sealant doesn’t bond well to old, weathered sealant, so we always take the old sealant out. Where a wall is exposed, as many are in small places like Sarsden, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
A few things move the cost up or down: the old material and how easily it comes out, any mould to treat, and whether we need extra access for height. We take all of that into account in your quote.
What you get with us
- Sanitary silicone with an anti-fungal additive in wet areas
- Domestic, commercial and hotel work
- Tidy, careful work
- Quality sealants from Arbo and Everbuild