Oxfordshire · England
External Mastic in Chilswell
Movement joints in Chilswell need attention? We cut out the old, prepare the joints and apply the right sealant.
- Panel joints letting water in
- Movement joints filled with mortar instead of sealant
- Hard, crazed mastic that has stopped moving
Surface by surface
Concrete and blockwork
Wide joints in concrete need the depth controlling carefully. Backing rod sized to the joint sets it so the sealant isn’t too deep.
Joints between dissimilar materials
Each side of the joint may need its own preparation. Both surfaces are cleaned and primed as the product requires.
How we handle external mastic in Chilswell
Many failed façade joints only get noticed once there’s a stain or a damp patch inside. We look over the joints, agree the ones to renew and reseal with a flexible, weatherproof product. If you’re dealing with moss and dirt in joints with no sealant left and movement joints filled with mortar instead of sealant, we can put it right, on render & cladding joints, concrete & block and copings & trims alike.
Outside joints can only be sealed when they’re dry, so work in Chilswell is booked around the forecast. Let us know about access to every wall, plus any garages or outbuildings.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we will put it right.
- Place
- Chilswell (OX1)
- Region
- Oxfordshire
- Cover
- A year, on every job
- Quotes
- A clear price before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
What we are called out for in Chilswell
Sunlight, wet weather and frost wear exterior sealant down. Over the years it hardens, cracks on the surface and loses its give, so the next time the wall moves, it splits or pulls away.
The problems people generally mention when they call are:
- Damp patches traced to an open external joint
- Failed sealant between panels on a façade
- Weeds or debris growing in open joints
- Brick movement joints where the sealant has split
Schools such as Matthew Arnold School are buildings too, and larger buildings have long runs of movement joint that eventually need resealing.
What your quote should include
- How the joint is cleaned and prepared
- How much experience the applicator has
- Is the old sealant removed completely?
- What product goes in the joint
Places near Chilswell
More services for Chilswell
Chilswell buildings and the weather
Historic houses like Holywell Manor (about 2.6 miles north-east) are a reminder that the area around Chilswell 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. 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.
For an older house near a landmark such as Church of St Lawrence, older walls, gutters and the joints where extensions meet them need a flexible sealant. Letting a property close to Oxford station? Then failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Chilswell is about 3 miles south-west of Oxford, in Oxfordshire. From the centre of Chilswell to the outskirts, external mastic is available for homes and businesses alike. Across Oxfordshire, we cover 443 places, Chilswell among them.
All of OX1 is covered for external mastic, from the main roads to the quietest streets. Close by, we work in Boars Hill (1 mile south), Hinksey Hill (1 mile east), Harcourt Hill (1 mile north), South Hinksey (1 mile north-east) and Bayworth (1 mile south). Larger places within reach include Oxford (3 miles north-east), Didcot (8 miles south), Bicester (13 miles north-east), Abingdon-on-Thames (3 miles south), Witney (10 miles north-west) and Carterton (13 miles west).
Landmarks near Chilswell
In Chilswell, that means homes and buildings near Raleigh Park, among other places. The nearest railway station is Oxford station, about 2 miles north of the centre. Other landmarks nearby include Westgate Shopping Centre (2 miles north-east) and Radcliffe Infirmary (2.6 miles north-east). Not far away are Harcourt Hill and Lashford Lane Fen.
How it works
On the day, we start by going over the job with you. Surfaces next to the work are protected before any work starts. Most jobs take anything from a few hours to several days, depending on the building. For a village or hamlet like Chilswell, the journey is planned in advance: let us know about lanes, gates and parking. Everything for the job comes with us, so a second trip is avoided where possible.
- We inspect the joints and agree which need resealing and how they’ll be reached.
- We cut out the failed sealant and rake out any dirt or growth.
- We clean both faces of the joint and prime them where the product calls for it.
- Backing rod goes in next, setting the depth and keeping the sealant off the back of the joint.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
How to prepare
- Tell us if parking is tricky
- For business premises, tell us about site rules or sign-in
- Move anything stored near the joints
How to get a quote
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints, and email pictures if that is easy.
Related advice
FAQs for Chilswell
Can you do external mastic in Chilswell?
Yes. We work across London and the South East, and Chilswell is part of that. Just ring 0345 464 0079 or email us with a few details of the job.
Will you come out to Chilswell?
Yes, we do. We work across London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
Is there any odour?
Some sealants have a smell while they cure, but it fades. Ventilation helps.
What’s an expansion joint in brickwork?
A vertical gap in a long brick wall is generally a movement joint. It lets the bricks expand without cracking and needs a flexible seal, not mortar.
How much does external mastic cost in Chilswell?
There’s no set price, as it depends on the job: how much there is, what’s there now, how we reach it and what it needs. You will get a clear quote before work begins.
Do you use backing rod?
Backing rod goes into deeper joints as a matter of course. It controls the depth and stops the sealant bonding to the back.
Do you have insurance?
Yes, we’re fully insured.
Do you do commercial work?
Yes. We work in offices, washrooms, hotels and other commercial premises, as well as homes. We can talk about working times when we quote.
DIY sealant or a professional job?
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
Overfilling a joint is a classic DIY mistake. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
Landlord and commercial work in Chilswell
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance.
From a single let to a portfolio, the work is the same standard: old sealant fully removed, joints prepared properly and a one-year guarantee.
How to look after the new joints
To keep the joints looking good and working properly:
- Keep high-pressure jets off the joints
- Keep movement joints as flexible joints, not mortar
- Don’t let climbing plants root in the sealant
- Leave the joints unpainted unless we have said otherwise
Keep the joints clear of soil, plants and climbing growth. Damp material against the sealant shortens its life.
A joint that has stopped moving pushes the movement elsewhere, generally as cracking in the brickwork or render nearby. Catch it early and you reduce the risk.
When it is not the sealant
We will always be straight with you, so here’s what sealant can’t fix:
- Walls that need new movement joints cut into them
- Movement that is more than a sealant joint can take
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
If you’re not sure, just call 0345 464 0079 or email us and we’ll give you a straight answer.
What we seal
- Concrete & block
- Copings & trims
- Brickwork movement joints
- Render & cladding joints
- Joints between brick and frames
- Façade panels