Slough · England
External & façade joints in Longford, Slough
Professional external mastic in and around Longford, with old sealant always removed completely.
- Moss and dirt in joints with no sealant left
- Rain getting behind render or cladding at a joint
- Joints with sealant missing in places
Longford questions
Is Longford in your area for external mastic?
Yes, Longford is within the area we cover. Our work covers London and the South East. Just call 0345 464 0079 or drop us an email with a few details of the job, and we’ll send you a clear quote.
Can you help a landlord with a rental near Heathrow Terminal 5 Rail station?
Yes, we work for landlords and agents. You can phone 0345 464 0079 or drop us an email with the address and a few details, and we will give you a fixed price before we start.
How long does the job take?
Most jobs take anything from a few hours to several days, depending on the building. We will confirm how long when we quote.
Where are you based?
We work from Crawley. We cover Longford and the rest of Slough.
How do you reach high-level joints?
It depends on the building. Tell us the height, the number of joints and what’s below them, and we will confirm what access is needed.
Do you have insurance?
Yes. We’re fully insured, and we can confirm the details when we quote.
How much does external mastic cost in Longford?
Size, access and the old material all affect the cost. Call for a quick quote.
Why is there a gap in my brick wall?
A movement joint is a planned break in the wall that absorbs expansion and shrinkage. It’s sealed with a flexible sealant, not mortar.
How we handle external mastic in Longford
Joints between dissimilar materials, like brick against render or concrete against a steel frame, see movement from both sides. A flexible exterior sealant takes up that movement where mortar or filler would crack. We work on copings & trims, façade panels and joints between brick and frames, and the jobs we see most are old sealant gone brittle and cracked and moss and dirt in joints with no sealant left.
In a village or hamlet like Longford, older cottages and farm buildings often stand in the open, so walls and rooflines take the full force of wind and rain. Gutter joints and wall joints there need a sealant that can flex and stay put.
Whatever the size of the job, you get the same 12-month guarantee in Longford and across Slough.
- Location
- Longford (SL3, UB7, TW6)
- Wider area
- Slough
- Cover
- One year on every job
- Quote
- A clear quote up front
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
When something else is needed
Before booking, it’s worth knowing the limits:
- Render that is blown, hollow or coming away
- Walls that need new movement joints cut into them
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
Not sure which it is? You can call 0345 464 0079 or email us and we will tell you honestly.
What we seal
- Copings & trims
- Façade panels
- Brickwork movement joints
- Render & cladding joints
- Joints between brick and frames
- Concrete & block
Work for landlords, hotels and businesses
We work for landlords and letting agents as well as householders. Resealing between tenancies is a simple way to keep a property in good order.
For anyone letting property in or around Longford, jobs at different addresses can go on one quote. Send us the addresses and the work at each.
Signs you need external mastic in Longford
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.
The most common problems we see are:
- Failed seals between different materials
- Leaking joints around cladding and façade panels
- Weathered mastic that no longer stretches
- Sealant that has lost its bond to the brick or render
For an older house near a landmark such as Church of St Mary, an extension built onto an older house moves differently, and the joint between them takes the strain.
What your quote should include
- What guarantee comes with the work
- How hidden problems are handled
- What the cure time is
- Which sealant they’ll use, and why
Walls and rooflines in Longford
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. Historic houses like Frogmore House (about 4.3 miles west) are a reminder that the area around Longford 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.
Letting a property close to Heathrow Terminal 5 Rail station? Then split movement joints are easy to miss on a rental until damp shows inside. If you look after a building such as Pippins School, larger buildings have long runs of movement joint that eventually need resealing.
Longford is about 2 miles south-west of West Drayton, in Slough. If you need external mastic in Longford, it’s easy to get a quote: please call 0345 464 0079 or send us an email. We are based in Crawley and cover Slough, Longford included. Our area takes in 31 places across Slough, from the larger towns to small villages. Our London page covers work nearby.
Here we cover the SL3, UB7 and TW6 postcode area for external mastic. If you need external mastic at a property on Wallis Road, Widgeon Road and Stanwell Moor Road or anywhere close by, our applicators can take on the job. Being close to the A3044, Longford is easy for our applicators to reach. Other places close to Longford include Harmondsworth (1 mile north-east), Stanwell (2 miles south-east), Heathrow (2 miles east), Sipson (2 miles north-east) and West Bedfont (2 miles south-east). We also work in nearby towns such as Slough (6 miles north-west), Cippenham (7 miles north-west), Chalvey (5 miles west), Britwell (7 miles north-west), Langley (3 miles north-west) and Upton (5 miles north-west).
Near you in Longford
We work in homes and buildings around The Kings Arms and Arthur Jacob Nature Reserve. For rail, the closest station is Heathrow Terminal 5 Rail station, roughly 0.5 miles south-east. A little further out are Windsor Castle (4.8 miles west) and Harlington (2.1 miles north-east). Not far away are Crane Meadows and Staines Reservoirs.
Surface by surface
Render joints
The face of render can be soft, so a low-modulus sealant is kinder to the joint edges. We prime where the product needs it.
Copings and trims
Coping joints that leak let water straight down into the wall. Resealing them is a small job that protects a lot.
Can I do it myself?
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.
The biggest DIY mistake is sealing over old sealant. New silicone won’t bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
The process
Every visit runs the same way: we check the joints, mask and protect the surrounding surfaces, do the work and tidy away. It usually takes a few hours to a few days, depending on the length of joint and the access. For a village or hamlet like Longford, the journey is planned in advance: let us know about lanes, gates and parking. We bring what the job needs, so it can be finished in one trip where possible.
- 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.
- Backing rod goes in next, setting the depth and keeping the sealant off the back of the joint.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Preparing for the visit
- Keep children and pets away from the work area
- Try not to wet indoor joints just before the visit
- Let us know about stairs, lifts or work at height
How to get a quote
For a quick quote, get us on the phone, or send an email if you’d rather. Tell us about the joints that need doing and we will explain what’s involved and give you a clear quote.
Related advice
How we quote for external mastic
The price is agreed before any work begins. It takes into account:
- The number and length of the joints
- The product the joint needs
- When we can work, for business premises
- Access and height
The cost depends on the amount of work, how much old material has to come out and access to the work. You’ll have a clear quote before any work starts.
What we need to know
What to tell us when you ask for a quote:
- Any access issues, like height or stairs
- Where the job is, and your postcode
- The problem you’ve noticed
- The type of property
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is, and email pictures if that’s easy.