Greater London · England
External & façade joints in Collier Row, Greater London
External mastic for Collier Row, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Joints with sealant missing in places
- Plants rooting in failed movement joints
- Sealant pulling away from one side of the joint
External mastic for homes and businesses in Collier Row
For buildings in Collier Row, 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, concrete & block and brickwork movement joints, and common reasons people get in touch are joints where the bead has come unstuck and movement joints with cracked, split or missing sealant.
London’s terraces and conversions often share walls, gutters and downpipes with their neighbours, so a leaking gutter joint or failed wall joint can affect more than one home. In a converted house in Collier Row, it’s worth checking who is responsible for the outside before booking.
Our work is backed for twelve months.
- Place
- Collier Row (RM1, RM5, RM7)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Quote
- A clear price before we start
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
What happens on the day
Most of a good job is in the preparation, so that’s where we spend the time. Every joint is cleaned and dried before new material goes in. In total, it generally takes a few hours for a handful of joints, longer for a whole elevation. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Collier Row. A visitor permit or a nearby bay makes the visit run more smoothly.
- First, the joints are inspected and the access agreed.
- Every bit of old sealant and any mortar or debris is cut out.
- Joint faces are cleaned back and primed if the sealant needs it.
- Backing rod sized to the joint goes in to set the depth.
- We apply the sealant, tool it and check the whole run.
Preparing for the visit
- Move anything stored near the joints
- Tell us if parking is tricky
- For business premises, tell us about site rules or sign-in
Ask for a quote
Every job is quoted individually. Simply ring 0345 464 0079 or email us and describe the job.
Related advice
Common questions in Collier Row
Can you do external mastic in Collier Row?
Yes, Collier Row is within the area we cover. Our work covers London and the South East. You can phone 0345 464 0079 or drop us an email and tell us what needs doing, and we will send you a clear quote.
Do you work for landlords with property near Romford station?
Yes, rental work is part of what we do. Just phone 0345 464 0079 or email us and tell us about the property, and we will send you a clear quote.
Is it OK to fill a movement joint with cement?
No, not where the gap is a movement joint. Filling it with mortar defeats its purpose. We will reseal it with a flexible sealant.
Does someone need to be in?
If the work is inside, we need someone to let us in. After that, you can carry on with your day.
How long does the job take?
Typically it takes a few hours to a few days, depending on the length of joint and the access. Larger jobs naturally take longer, and we’ll tell you how long to expect.
Where is Mr Mastic based?
We are based in Crawley, West Sussex, and we work across South East England, London and Scotland.
What is a movement joint?
Walls move with heat, cold and moisture, so long walls have planned gaps to take that movement. It’s closed with backing rod and a flexible sealant.
Do you remove the old sealant?
Yes, always, and completely. New silicone does not stick to old silicone, so any old material comes out before anything new goes in.
What we cannot put right
Before you book, it’s worth knowing the limits too:
- Cracks in the bricks or render themselves, away from the joints
- Movement that’s more than a sealant joint can take
- Loose or hollow render, which needs re-rendering
If you are not sure, just phone 0345 464 0079 or drop us an email and we’ll give you a straight answer before booking.
Surfaces we seal
- Brickwork movement joints
- Copings & trims
- Render & cladding joints
- Concrete & block
- Façade panels
- Joints between brick and frames
Landlord and commercial work in Collier Row
Mouldy or split sealant often shows up at the end of a tenancy. Several properties can go on one quote.
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 that we can handle for you.
How to look after the new joints
No joint lasts for ever, but care makes a real difference. Our tips:
- Act on the first splits you see
- Never let anyone fill a movement joint with mortar
- Fix overflowing gutters above sealed joints
- Wash walls gently around the sealant
Only paint over the joint if we’ve confirmed the sealant can take paint. Many exterior sealants aren’t designed to be painted.
Leaks behind façade panels and render often go unseen. When it finally shows inside, the joint may have been open for years so early resealing is worth it.
Do you need external mastic in Collier Row?
Weeds, moss and debris in a joint are a sign the sealant has gone. Roots and dirt hold water against the wall and make things worse.
Common reasons people contact us are:
- Gaps where render, brick and frames meet
- Weathered mastic that no longer stretches
- Sealant that has lost its bond to the brick or render
- Movement joints with cracked, split or missing sealant
Letting a property close to Romford station? Then outside joints that have cracked can let damp into a rental, so check them between lets.
What your quote should include
- What the quote includes, VAT included or not
- How the surfaces are prepared before sealing
- What happens if the job turns out different
- Whether they seal over old material or remove it
Nearby places to Collier Row
More services for Collier Row
Collier Row buildings and the weather
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. In terraces and conversions, gutters and walls are often shared with the neighbours, so check who is responsible for the outside before booking.
Collier Row is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. Historic houses such as Hare Hall, about 1.7 miles east, show how far back building around Collier Row goes, and older homes nearby need a sealant that suits their walls.
Collier Row is about 1 mile north of Romford, in Greater London. For external mastic in and around Collier Row, it’s easy to get a quote: please call 0345 464 0079 or send us an email. We are based in Crawley and cover Greater London, Collier Row included. Collier Row is one of 764 places in Greater London we cover for external mastic. There’s also a page for London, about 13 miles away.
Postcode districts we cover here for external mastic: RM1, RM5 and RM7. Whether your property is on Elm Road, Percy Road and Seymer Road or a nearby road, we can help. Other places close to Collier Row include Rise Park (1 mile north-east), Romford (1 mile south), Marks Gate (1 mile west), Chadwell Heath (2 miles south-west) and Rush Green (2 miles south). Larger places within reach include London (13 miles south-west), City of Westminster (15 miles west), Marylebone (15 miles west), St Pancras (13 miles west), Shoreditch (12 miles south-west) and Walthamstow (8 miles west).
Landmarks near Collier Row
Around Collier Row, our work takes us to homes and buildings near Colley Rowe Inn, Marshalls Park Academy and Raphael Park and the streets around them. The closest station to Collier Row is Romford station, roughly 1.3 miles south. A little further out are Romford Shopping Hall (1 mile south) and Oldchurch Hospital (1.5 miles south). Not far away are Bedfords Park.
How the job changes by surface
Brickwork movement joints
Vertical joints in long brick walls let the brickwork expand without cracking. We reseal them with a low-modulus sealant over backing rod coloured to suit the wall.
Copings and trims
Coping joints that leak let water straight down into the wall. Resealing them is a small job that protects a lot.
Should I try it myself first?
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.
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.