Oxfordshire · England
External Mastic in Postcombe
Problem with your movement joints in Postcombe? We remove the old material, prepare the joints and seal them properly, and the work is guaranteed for a year.
- Failed sealant between panels on a façade
- Gaps where render, brick and frames meet
- Joints pointed up with cement by mistake
Why it’s worth doing now in Postcombe
The longer a joint stays open, the more water the wall takes in. Wet masonry is more easily damaged by frost near the open joint, so the damage spreads beyond the joint. Where a wall is exposed, as many are in small places like Postcombe, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
What you pay reflects the work, not guesswork. That’s why we ask about the job first and agree the price before starting.
What you get with us
- Trusted Arbo and Everbuild sealants
- Approved under the ARBOMaster scheme
- A 12-month guarantee on all work
- Anti-fungal sanitary silicone in wet areas
Take a look at what affects the cost or our reviews.
External mastic for homes and businesses in Postcombe
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, and when it fails, the wall takes the strain and water finds a way in. If you are dealing with rain getting behind render or cladding at a joint and cracked joints where brick meets render or frames, we can help, whatever the surface.
Older homes in small places like Postcombe may be stone, brick or timber-framed, often with later extensions. Where one material meets another is where water generally gets in, and they need the right sealant at the right depth.
The work is covered for a year after we finish. If anything isn’t right with it, call 0345 464 0079 or email us.
- Where
- Postcombe (OX9)
- Region
- Oxfordshire
- Guarantee
- A year, on every job
- Price
- A clear price before we start
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Towns and villages near Postcombe
More services for Postcombe
DIY sealant or a professional job?
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and doesn’t move well, and getting the depth right matters as much as the look.
The process
When we get to you, we compare the joints with what we discussed. If we find something unexpected, we talk it through with you first. Most jobs then take a few hours to a few days, depending on the length of joint and the access. In a small place like Postcombe, access is normally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- Joint faces are cleaned back and primed if the sealant needs it.
- We fit closed-cell backing rod to control the depth.
- The exterior sealant is applied, tooled and checked along its length.
Before we arrive
- Keep pets and children clear of the area while we work
- Let us know about earlier repairs to the joints
- Let us know if you’ve seen damp or leaks
Get a quote
Want a quote for external mastic? Please call 0345 464 0079 or send us an email with a few details. We will explain what we’d do and send you a clear quote before any work starts.
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Outside joints around Postcombe
Historic houses like Adwell House (about 0.8 miles west) are a reminder that the area around Postcombe has older buildings as well as new. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. 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.
In and around Postcombe, as anywhere, good external mastic starts with a clean, dry, properly prepared joint.
Postcombe is about 4 miles south of Thame, in Oxfordshire. Every kind of property in Postcombe can book us for external mastic. The work is guaranteed for a year. We cover 443 towns and villages across Oxfordshire, large and small. Our Oxford page covers work nearby, about 12 miles away.
Here we cover the OX9 postcode area for external mastic. Whether your property is on London Road, Salt Lane and Beech Farm Close or a nearby road, our applicators can take on the job. Nearby, we also carry out external mastic in South Weston (1 mile south-west), Aston Rowant (1 mile east), Lewknor (1 mile south), Kingston Blount (2 miles east) and Crowell (2 miles east). Within a short drive, we also cover Oxford (12 miles west), Didcot (13 miles south-west), Abingdon-on-Thames (13 miles west), Thame (4 miles north), Henley-on-Thames (11 miles south) and Benson (7 miles south-west).
Local landmarks in Postcombe
In Postcombe, that means homes and buildings near England's Rose pub. A little further out are Thame Community Hospital (3.8 miles north). For a walk, there’s Aston Rowant NNR and Bald Hill.
Postcombe questions
Is Postcombe within the area you cover?
Yes, we do. Our work covers London and the South East, from towns to the smallest places. The journey is planned ahead, so it helps to know about access.
Is external mastic in Postcombe guaranteed?
Every job comes with our 12-month guarantee, wherever it is. We are also fully insured and ARBOMaster approved.
What is backing rod for?
We fit closed-cell backing rod wherever the joint depth needs controlling. It sets the sealant depth and prevents three-sided bonding so the bead can stretch.
Will there be a smell?
Some sealants have a smell while they cure. Opening a window helps.
Can tenants book the work?
Yes. Check with your landlord; we can send the quote to them too.
Should I try DIY first?
Some simple jobs can be done by a careful DIYer. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Can you work on commercial sites?
Yes. We work in offices, washrooms, hotels and other commercial premises. We can talk about working times when we quote.
What do you need from me for a quote?
The location, the problem and the rough size of the job. If you can, email a few photos.
Work for landlords, hotels and businesses
Whether it’s one flat or a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a one-year guarantee.
Failed sealant is one of the commonest items on a check-out report, and it’s easy to sort out between tenants. Several properties can go on one quote.
Looking after it afterwards
Good habits help new joints last longer. A few tips:
- Have failed joints looked at early
- Never let anyone fill a movement joint with mortar
- Keep water from gutters off the wall
- Keep soil, plants and ivy away from the joints
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.
Water getting behind cladding or render can go unnoticed for a long time. By the time there’s a damp patch, the damage can be well established, so it’s worth resealing at the first signs.
Different surfaces, different methods
Copings and trims
Copings expand and contract through the day, so the joints need a sealant that stays flexible year round.
Concrete and blockwork
Concrete faces can be dusty and porous, so cleaning and priming matter. We prime where the sealant needs it.
Signs you need external mastic in Postcombe
Buildings move more than people expect. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. The sealant in the movement joints takes that strain.
Look out for these signs:
- Cracked joints where brick meets render or frames
- Rigid filler in a joint that should flex
- Water getting into walls through failed joints
- Weeds or debris growing in open joints
Homes close to Church of St Mary include some older properties, and older walls, gutters and the joints where extensions meet them need a flexible sealant.
Comparing quotes
- How hidden problems are handled
- How the surfaces are prepared before sealing
- What the cure time is
- Who turns up on the day