Oxfordshire · England
External & façade joints in Didcot, Oxfordshire
Sealing brickwork movement joints, render, cladding and façade joints for homeowners, landlords and businesses in Didcot. Fully insured, ARBOMaster approved and guaranteed for a year.
- Water getting into walls through failed joints
- Sealant pulling away from one side of the joint
- Hard, crazed mastic that has stopped moving
When something else is needed
We’ll always be straight with you, so here’s what sealant cannot fix:
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
- Walls that need new movement joints cut into them
- Structural movement, which needs a surveyor or engineer
If you are not sure, just call 0345 464 0079 or drop us an email and we will give you a straight answer before you book.
What we seal
- Copings & trims
- Brickwork movement joints
- Joints between brick and frames
- Render & cladding joints
- Concrete & block
- Façade panels
External mastic in Didcot
Where two different materials meet, such as brick and render or blockwork and metal, they move at different rates. A flexible sealant bridges the two. If you are dealing with hard, crazed mastic that has stopped moving and gaps where render, brick and frames meet, we can help.
Around Didcot, outside jobs take in garage door frames, porches, gutters and trims as well as walls. Where two materials meet, they move differently, and the sealant has to allow for it.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we’ll put it right.
- Where
- Didcot (OX11)
- Region
- Oxfordshire
- Cover
- A year, on every job
- Quotes
- A clear price before work begins
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
The process
We keep the work tidy and contained to the area we are working on. Expect the work to take a few hours to a few days, depending on the length of joint and the access, and we tell you how long to leave it before we go. Parking in a town like Didcot is usually straightforward, but tell us if there’s a driveway or any restrictions, and let us know if the work is upstairs, in a flat or up high outside.
- We start by walking round the building and agreeing the joints and the access.
- 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.
- We apply the sealant, tool it and check the whole run.
How to prepare
- Plan for the work area to be out of bounds to pets and children
- Mention any leaks or damp you’ve noticed
- Tell us about access, such as stairs, a lift or high-level joints
How to get a quote
Quotes start with a quick conversation. Describe the problem, the location and the size of the job. Whenever you’re ready, phone 0345 464 0079 or send us an email.
Advice
Different surfaces, different methods
Cladding and façade panels
Metal and composite panels move a lot with temperature, so the joints work hard every day. The sealant is chosen with that in mind.
Brickwork movement joints
Brick movement joints are often mistaken for a missing mortar line. If that’s happened, we rake it out and reseal it properly where it can be done safely.
Towns and villages near Didcot
What else we do in Didcot
DIY sealant or a professional job?
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Outside joints around Didcot
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. Historic houses like Brightwell Manor (about 3.4 miles east) are a reminder that the area around Didcot 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.
For landlords with property near Didcot Parkway station, failed wall and movement joints let damp in, so they’re worth checking between tenancies. Managing a site like Manor Primary School? Then larger buildings have long runs of movement joint that eventually need resealing.
Didcot is about 10 miles south of Oxford, in Oxfordshire. Our applicators cover external mastic for homes and businesses in Didcot and nearby, as part of our work across Oxfordshire. 443 places in Oxfordshire are on our list. Our Oxford page covers work nearby.
Jobs for external mastic in OX11 is quoted and booked the same way as anywhere else. If you need external mastic at a property on Station Road, Market Place and High Street or a nearby road, we can help. Being close to the A4130 and B4016, Didcot is easy for our applicators to reach for external mastic. We also cover the places around Didcot: Great Western Park (1 mile west), Appleford-on-Thames (2 miles north), Milton (2 miles north-west), Sutton Courtenay (2 miles north-west) and Long Wittenham (3 miles north-east). We also work in nearby towns such as Oxford (10 miles north), Abingdon-on-Thames (5 miles north), Thame (15 miles north-east), Wantage (8 miles west), Grove (8 miles west) and Faringdon (15 miles west). As one of the bigger places in Oxfordshire, Didcot has every kind of property, from flats to offices.
Local landmarks in Didcot
We work in homes and buildings around Didcot Girls' School, The Queens Arms and UTC Oxfordshire, among other places. Didcot has its own railway station: Didcot Parkway station. Other landmarks nearby include Abingdon Community Hospital (4.8 miles north-west) and Brightwell Castle (3.4 miles east). Not far away are Mowbray Fields and Wittenham Clumps.
Didcot questions
Can you help a landlord with a rental near Didcot Parkway station?
Yes, we work for landlords and agents. You can ring 0345 464 0079 or email us with the address and a few details, and we will give you a fixed price before we start.
What guarantee comes with external mastic in Didcot?
All our work, in Didcot and everywhere else, comes with a 12-month guarantee. We’re fully insured, and an ARBOMaster approved applicator.
How long does external mastic take?
A typical job takes a few hours for a handful of joints, longer for a whole elevation, including preparation and clearing up. Your quote will say how long we expect yours to take.
Can you seal joints between two different materials?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. The colour is chosen to suit.
Is it OK to seal over old sealant?
No. Fresh sealant does not stick to old sealant, and anything trapped underneath, including mould and water, stays there. We remove it all first.
Are you an approved applicator?
Yes. Mr Mastic is an ARBOMaster approved applicator and we are fully insured too.
Can a movement joint be filled with mortar?
No. Rigid materials can’t move with the wall and the joint fails. Where a joint has been mortared, it can often be raked out and sealed properly.
Which products do you use?
Products from Arbo and Everbuild, among others, picked for each joint. We explain the product when we quote.
Signs you need external mastic in Didcot
Sometimes a movement joint was filled with mortar or a rigid filler. The joint cannot move, so the wall cracks somewhere else instead.
Any of these means the joints need attention:
- Damp patches traced to an open external joint
- Leaking joints around cladding and façade panels
- Movement joints filled with mortar instead of sealant
- Moss and dirt in joints with no sealant left
In the older streets around Church of All Saints, an extension built onto an older house moves differently, and the joint between them takes the strain.
What to look for in a quote
- What the cure time is
- Is VAT in the price?
- Who does the work, and how experienced they are
- Is the old sealant removed completely?
Landlord and commercial work in Didcot
Landlords and letting agents in Didcot can book us as well as homeowners. Resealing between tenancies keeps a property looking cared for.
In hotels, rooms out of use cost money, so the work can be planned room by room. We have worked in hotels as well as homes and businesses.
Keeping the joints in good condition
No joint lasts for ever, but care makes a real difference. A few tips:
- Point out the joints to other trades
- Have failed joints looked at early
- Deal with leaking gutters that soak the joints below
- Avoid pressure-washing directly into sealant joints
Avoid pressure-washing straight into the joints. High-pressure water can lift the edges and let water in behind.
Water getting behind cladding or render can go unnoticed for a long time. When it finally shows inside, the joint may have been open for years, so it’s worth resealing at the first signs.