Greater London · England
Pinner External Mastic
Sealing brickwork movement joints, render, cladding and façade joints for Pinner, backed by a 12-month guarantee. Ask us for a quote.
- Weeds or debris growing in open joints
- Leaking joints around cladding and façade panels
- Rain getting behind render or cladding at a joint
External mastic for homes and businesses in Pinner
For buildings in Pinner, we reseal external joints of all kinds, from brick movement joints to cladding panels. Every joint gets the same careful preparation: clean, sound faces and a controlled depth. We work on façade panels, joints between brick and frames and render & cladding joints, and people most often call us about sealant that has lost its bond to the brick or render and leaking joints around cladding and façade panels.
Outside work in London starts with access: side passages, upper floors and where to park. For a home in Pinner, tell us how high the joints are and how to reach the back of the building.
Every job comes with a 12-month guarantee.
- Place
- Pinner (HA5)
- Wider area
- Greater London
- Guarantee
- A year, on every job
- Quote
- A clear price before we start
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
The process
A visit follows a simple pattern: we look at the joints together, protect the area around them, carry out the job and clear up. It generally takes a few hours for a handful of joints, longer for a whole elevation. In Pinner, as in most of London, parking needs a little planning. It helps if you can point us to a visitor permit or a bay close to the door.
- We start by checking each joint, agreeing the ones to redo and how we’ll reach them.
- 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.
- We push in closed-cell backing rod so the sealant is the right depth and bonds to the sides only.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
Getting ready for the visit
- Let us know about stairs, lifts or work at height
- Try not to wet indoor joints just before the visit
- Mention any leaks or damp you’ve noticed
How to get a quote
We quote each job on its own. Just ring 0345 464 0079 or email us with the details.
Advice
Signs you need external mastic in Pinner
If plants are growing out of a joint, the sealant has usually failed or was never there. Dirt and roots then trap moisture in the joint and make things worse.
It’s worth asking for a quote if you see:
- Plants rooting in failed movement joints
- Weathered mastic that no longer stretches
- Rain getting behind render or cladding at a joint
- Movement joints with cracked, split or missing sealant
Schools such as West Lodge Primary School are buildings too, and larger buildings have long runs of movement joint that eventually need resealing.
Comparing quotes
- What insurance they hold
- What guarantee comes with the work
- What preparation is included
- What product goes in the joint
When something else is needed
We will always be straight with you, so here’s what sealant cannot fix:
- Cracking across the wall rather than at a joint
- Structural movement, which needs a surveyor or engineer
- Cutting new joints into brickwork, which is building work rather than sealant work
Not sure which it is? You can call 0345 464 0079 or send us an email and we will tell you honestly.
Where we work in Pinner
- Façade panels
- Concrete & block
- Joints between brick and frames
- Render & cladding joints
- Brickwork movement joints
- Copings & trims
What external mastic looks like in Pinner
In terraces and conversions, gutters and walls are often shared with the neighbours, so check who is responsible for the outside before booking. Historic houses like Headstone Manor (about 1.5 miles east) are a reminder that the area around Pinner 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 Hatch End station? Then split movement joints are easy to miss on a rental until damp shows inside. In the older streets around Christian Science Church, an extension built onto an older house moves differently, and the joint between them takes the strain.
Pinner is about 1 mile north-east of Ruislip, in Greater London. Jobs in Pinner get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Our Greater London coverage runs to 764 places, Pinner among them. London is on our list too, around 14 miles away.
All of HA5 is within our area for external mastic, from the main roads to the quietest streets. Local streets include Love Lane, Tudor Road and Marsh Road, all of which we cover. Neighbouring places we cover for external mastic include Pinner Green (1 mile north-west), Eastcote (1 mile south), North Harrow (1 mile south-east), Roxbourne (1 mile south) and Rayners Lane (2 miles south-east). Within a short drive, we also cover London (14 miles south-east), City of Westminster (12 miles south-east), Marylebone (12 miles south-east), Kensington (10 miles south-east), St Pancras (13 miles east) and Shoreditch (14 miles east).
Landmarks near Pinner
Around Pinner, our work takes us to homes and buildings near Pinner High School, Heathfield School and The Oddfellows Arms. For rail, the closest station is Hatch End station, roughly 1.4 miles north-east. Other landmarks nearby include Northwood and Pinner Cottage Hospital (1.3 miles north-west) and St. George's Shopping Centre (2.3 miles east). Open spaces near Pinner include Horse Shoe Bay and Northala Fields.
What else we do in Pinner
Keeping the joints in good condition
A little care helps the new joints last. Our advice:
- Keep movement joints as flexible joints, not mortar
- Avoid pressure-washing directly into sealant joints
- Look over the joints every year, ideally after winter
- Check the sealant is paintable before painting near it
Keep the joints clear of soil, plants and climbing growth. Damp material against the sealant shortens its life.
Gaps, plants or missing sealant in a joint are worth getting looked at. Early work is quicker and leaves a better finish.
For landlords and businesses
Failed sealant is one of the commonest items on a check-out report, and it’s quick to put right between tenancies. Several properties can be quoted together.
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements.
Can I do it myself?
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
If you’ve already had a go yourself, that is fine. We cut it out and start again, so just mention it when you contact us.
What the job involves on each surface
Render joints
Render is weaker at the surface than brick, so a low-modulus sealant is kinder to the joint edges. Priming is done where the sealant calls for it.
Brickwork movement joints
Brick moves with heat and moisture, and grows a little over time. That movement goes into the joint, so the sealant in it must stay soft and stretchy.
Pinner questions
Is Pinner in your area for external mastic?
Yes. Our work covers London and the South East, and Pinner is part of that. You can phone 0345 464 0079 or drop us an email and let us know what needs doing.
Do you work for landlords with property near Hatch End station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. Just call 0345 464 0079 or email us with the address and what needs doing, and we will give you a clear quote.
Do you work for hotels and businesses?
Yes. Larger jobs can be planned room by room or area by area to suit the site.
Can you seal over the old sealant?
No. Fresh sealant does not stick to old sealant, and it traps any mould or water underneath. It all has to come out first.
Do you seal joints where cladding meets other materials?
Yes. We cut out the old sealant, prepare both faces and reseal with a flexible exterior product. We pick a colour that works with both materials.
What does external mastic cost?
We don’t publish prices, because the cost depends on the job: how much there is, what’s there now, how we reach it and what it needs. You’ll get a clear quote before any work starts.
Do I have to be there?
If the work is inside, we need someone to let us in. Once we have agreed the job, you don’t need to watch us work.
How long before the joint can be used?
Most sealants are touch-dry well before they’re fully cured. We will tell you how long to leave the joint.