Surrey · England
Sunbury-on-Thames External Mastic
Sealing brickwork movement joints, render, cladding and façade joints in Sunbury-on-Thames, with a 12-month guarantee on every job. Ask us for a quote.
- Movement joints with cracked, split or missing sealant
- Movement joints filled with mortar instead of sealant
- Failed sealant between panels on a façade
About our external mastic in Sunbury-on-Thames
Movement joints let brickwork, render and cladding expand and shrink without cracking. 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. We work on render & cladding joints, façade panels and brickwork movement joints, and the jobs we see most are moss and dirt in joints with no sealant left and sealant pulling away from one side of the joint.
In a town like Sunbury-on-Thames, older houses with traditional gutters sit alongside newer estates with uPVC rooflines and rendered walls. Gutter joints, fascia trims and the movement joints in newer brickwork all need sealant that can flex.
You are covered for a year from the day we finish. If anything is not right with it, phone 0345 464 0079 or drop us an email.
- Location
- Sunbury-on-Thames (TW16)
- Region
- Surrey
- Guarantee
- One year on every job
- Quotes
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Signs you need external mastic in Sunbury-on-Thames
Some movement joints have been pointed up with mortar, often by someone who didn’t know what it was for. The joint cannot move, so the wall cracks somewhere else instead.
Signs it’s time to call us include:
- Joints where the bead has come unstuck
- Old sealant gone brittle and cracked
- Movement joints filled with mortar instead of sealant
- Plants rooting in failed movement joints
For landlords with property near Sunbury station, split movement joints are easy to miss on a rental until damp shows inside.
What to look for in a quote
- What guarantee comes with the work
- What insurance they hold
- Which colour the sealant will be
- Whether they seal over old material or remove it
FAQs for Sunbury-on-Thames
Can you do external mastic in Sunbury-on-Thames?
Yes, Sunbury-on-Thames is within the area we cover. Our work covers London and the South East. Just ring 0345 464 0079 or drop us an email with a few details of the job.
Do you work for landlords with property near Sunbury station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. Just ring 0345 464 0079 or drop us an email with the address and what needs doing, and we’ll give you a clear price.
Will there be a smell?
There can be a smell while the sealant cures, but it fades. Opening a window helps.
How long does the job take?
That depends on how much there is to do, but most jobs take a few hours for a handful of joints, longer for a whole elevation. We’ll tell you when we quote.
Will the old sealant be removed?
Yes. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Do you do commercial work?
Yes. Larger jobs can be planned room by room or area by area.
How do I get a quote for external mastic in Sunbury-on-Thames?
It depends on the job, so we quote each one individually. To get one, phone 0345 464 0079 or email us and let us know what needs doing and where.
Do I need to be at home?
That depends on where the joints are. Inside work needs someone to give us access.
Can I do it myself?
A DIY attempt does not rule out a professional job. We cut it out and start again, so just mention it when you contact us.
If you do try it yourself, take your time over the preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
The process
There is not much for you to do on the day. Show us the job and we will take it from there. The job generally takes anything from a few hours to several days, depending on the building from start to finish. In Sunbury-on-Thames, parking is rarely complicated, though it helps to know about driveways or restrictions, and let us know if the work is upstairs, in a flat or up high outside.
- We inspect the joints and agree which need resealing and how they’ll be reached.
- The old mastic and anything lodged in the joint is removed.
- We clean both faces of the joint and prime them where the product calls for it.
- We push in closed-cell backing rod so the sealant is the right depth and bonds to the sides only.
- We gun in a flexible exterior sealant in a colour that suits the wall and tool it neatly.
How to prepare
- Tell us about access, such as stairs, a lift or high-level joints
- Try not to wet indoor joints just before the visit
- Move anything stored near the joints
Ask for a quote
Want a quote for external mastic? Please phone 0345 464 0079 or send us an email and tell us about the job. We’ll explain what we’d do and give you a clear price before any work starts.
Advice
Keeping the joints in good condition
To keep the joints looking good and working properly:
- Keep soil, plants and ivy away from the joints
- Look over the joints every year, ideally after winter
- Avoid pressure-washing directly into sealant joints
- Deal with leaking gutters that soak the joints below
Make sure anyone working on the wall later knows where the movement joints are. They must stay as flexible joints, never rendered or pointed over.
Small splits are the time to act. Then it’s a straightforward cut-out and reseal with no damage behind it to deal with.
Towns and villages near Sunbury-on-Thames
More services for Sunbury-on-Thames
Walls and rooflines in Sunbury-on-Thames
With historic houses such as Hampton Court Palace (about 3.5 miles east) nearby, there’s older building stock in the area around Sunbury-on-Thames as well as newer homes. Where a home is older, 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, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Homes close to St Saviour include some older properties, and old and new materials meet at the roofline and walls, which is where sealant earns its keep. For site and facilities teams at buildings such as St Ignatius RC Primary School, its movement joints, gutters and trims need looking after like any other building’s.
Sunbury-on-Thames is about 7 miles south of Hayes, in Surrey. Every kind of property in Sunbury-on-Thames can book us for external mastic. Every job comes with our one-year guarantee. Our area takes in 395 places across Surrey, from the larger towns to small villages. We also work in London, about 15 miles from Sunbury-on-Thames.
Work in TW16 works the same way as everywhere else we cover. Local streets include Station Road, The Ridings and Ravenscourt, and we cover them all. With the A244 and A308 close by, Sunbury-on-Thames is simple for us to get to for external mastic. Other places close to Sunbury-on-Thames include Upper Halliford (1 mile south-west), Charlton (1 mile west), Ashford Common (1 mile north-west), Hounslow (1 mile north) and Littleton Common (1 mile west). We also work in nearby towns such as Guildford (13 miles south-west), Woking (10 miles south-west), Camberley (15 miles south-west), Epsom (8 miles south-east), Ewell (8 miles south-east) and Egham (6 miles west).
Around Sunbury-on-Thames
Locally, jobs take us to homes and businesses close to Sunbury Manor School, The Three Fishes Public House and Sunbury Park. Sunbury-on-Thames has its own railway station: Sunbury station. Nearby you’ll also find Kempton Steam Museum (1 mile north-east) and No. 2 New Zealand General Hospital (2 miles south). Not far away are St Ann's Hill and Kempton Park Reservoirs.
What sealant work cannot fix
Sealant is not the answer to every problem, and we will tell you before work begins. Sealant will not put right:
- Loose or hollow render, which needs re-rendering
- Damp that is not coming from the joint
- Movement that is more than a sealant joint can take
Not sure which it is? You can phone 0345 464 0079 or email us and we will tell you honestly before you book.
Joints and surfaces we work on
- Copings & trims
- Concrete & block
- Render & cladding joints
- Joints between brick and frames
- Façade panels
- Brickwork movement joints
Landlords, agents and businesses in Sunbury-on-Thames
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Resealing at the right time is simple maintenance that we can handle for you.
We also work for property managers and facilities teams in Sunbury-on-Thames and across Surrey. Several sites can go on one quote.
Why deal with it now?
Water gets in through a failed movement joint. Resealing early keeps the job to the joint itself, rather than the wall around it. In a family home in Sunbury-on-Thames, a failed seal around a bath or a frame lets water into places you cannot see, such as under the floor, behind a panel or into a wall. Whatever the joint, failed sealant only gets worse.
The cost reflects the work involved, not a rough estimate. That is why we ask about the job first and agree the price before starting.
What you get with us
- Sealant colour chosen to suit
- Fully insured
- We leave the area clean and tidy
- Rated 4.9 stars on Google
See our cost guide and our reviews.