Greater London · England
External & façade joints in North Cray, Greater London
Problem with your movement joints in North Cray? We cut out the old, prepare the joints and apply the right sealant.
- Failed sealant between panels on a façade
- Joints with sealant missing in places
- Gaps where render, brick and frames meet
How we handle external mastic in North Cray
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 a rigid filler would soon crack. If you have joints pointed up with cement by mistake and moss and dirt in joints with no sealant left, we can put it right.
In London terraces and converted houses, gutters and walls are often shared with the house next door, so a leaking gutter joint or failed wall joint can affect more than one home. For a flat in North Cray, check the lease for who looks after the outside.
All our work is covered by a one-year guarantee.
- Location
- North Cray (DA14)
- Wider area
- Greater London
- Cover
- A year, on every job
- Quotes
- A clear price before work begins
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
What happens on the day
There isn’t much for you to do on the day. Point us to the joints and we’ll get on with it. The work itself takes a few hours to a few days, depending on the length of joint and the access. In a London area like North Cray, the main things to plan are parking and access: tell us about permits, visitor bays or off-street space, which floor we’re working on and whether there’s a lift.
- First, the joints are inspected and the access agreed.
- Every bit of old sealant and any mortar or debris is cut out.
- The faces are brushed clean and primed where the product requires 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
- Where the joints are inside, avoid wetting them before we arrive
- Move anything stored near the joints
- Mention any sign-in or site rules at work premises
Ask for a quote
We quote each job on its own. Simply phone 0345 464 0079 or email us and describe the job, and pictures are welcome.
Related advice
Places near North Cray
Other services in North Cray
Outside joints around North Cray
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 Hall Place and Gardens (about 1.4 miles north-east) are a reminder that the area around North Cray has older buildings as well as new. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth.
For an older house near a landmark such as Parish Church of St James, older walls, gutters and the joints where extensions meet them need a flexible sealant. North Cray is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
North Cray is about 2 miles east of Sidcup, in Greater London. If you need external mastic in North Cray, please call 0345 464 0079 or send us an email for a quick quote. We’re based in Crawley and cover Greater London. North Cray is one of 764 towns and villages in Greater London we cover for external mastic. You can also see our page for London, roughly 11 miles from North Cray.
Our applicators cover all of DA14 for external mastic. Whether your property is on Water Lane, North Cray Road and Leafield Lane or anywhere close by, our applicators can take on the job. Neighbouring places we cover for external mastic include Bexley (1 mile north), Coldblow (1 mile north-east), Ruxley (1 mile south), Blendon (1 mile north-west) and Joyden's Wood (1 mile east). Further out, we also cover London (11 miles north-west), City of Westminster (14 miles north-west), Marylebone (14 miles north-west), Kensington (15 miles west), St Pancras (13 miles north-west) and Shoreditch (11 miles north-west).
What’s near North Cray
We work in homes and buildings around Foots Cray Meadows, Cleeve Park School and The White Cross pub and the streets around them. North Cray’s nearest station is Albany Park station, roughly 0.6 miles north-west. Nearby you’ll also find Broadway Shopping Centre (1.7 miles north) and Bexley Hospital (1.8 miles north). Not far away are Wansunt Pit and Summer Hill.
Different surfaces, different methods
Brickwork movement joints
Brick movement joints are often mistaken for a missing mortar line. Where one has been mortared, we cut it out and reseal it with sealant if the joint can be cleared.
Concrete and blockwork
Blockwork and concrete shrink over time and move with the seasons. We reseal their joints with backing rod and a flexible product.
Signs you need external mastic in North Cray
Many joints fail because they were sealed too deep or with nothing behind them. Sealant bonded to three sides has nowhere to go and tears as soon as the joint widens.
Keep an eye out for these signs:
- Weeds or debris growing in open joints
- Leaking joints around cladding and façade panels
- Joints pointed up with cement by mistake
- Sealant pulling away from one side of the joint
If you look after a building such as Royal Park Primary Academy, its movement joints, gutters and trims need looking after like any other building’s.
Questions to ask before you book
- Which sealant they’ll use, and why
- How the surfaces are prepared before sealing
- Is the old sealant removed completely?
- What happens if they find a problem under the old sealant
When something else is needed
New sealant cannot fix everything, and we will tell you before we start. It will not solve:
- Structural movement, which needs a surveyor or engineer
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
- Cracks in the bricks or render themselves, away from the joints
Not sure which it is? You can call 0345 464 0079 or send us an email and we’ll tell you honestly.
Surfaces we seal
- Copings & trims
- Brickwork movement joints
- Joints between brick and frames
- Façade panels
- Render & cladding joints
- Concrete & block
Can I do it myself?
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and getting the depth right matters as much as the look.
If you’ve already had a go yourself, that’s fine. We cut it out and start again, so just mention it when you contact us.
What affects the cost of external mastic
We quote each job individually. This is what makes a difference:
- How many areas need sealing
- The number and length of the joints
- When we can work, for business premises
- Mould in or behind the old joints
Every job is a little different, so each one gets its own quote. Size, access and the product the joint needs all play a part, and we’ll explain the quote if you ask.
Helping us quote
Photos by email are helpful but not essential. Try to tell us:
- The rough size of the job
- How we’d reach the joints
- Where the job is, and your postcode
- If it’s domestic, commercial or a hotel
It all starts with a short chat. Describe the problem, the location and the size of the job, and we’ll explain how we’d tackle it. When it suits you, phone 0345 464 0079 or send us an email.
Common questions in North Cray
Can parking be tricky for a visit in North Cray?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
Do you cover North Cray for external mastic?
Yes. Our work covers London and the South East, and North Cray is part of that. You can ring 0345 464 0079 or send us an email and let us know what needs doing, and we will send you a clear quote.
What sealant do you use?
We choose the sealant for the joint, not the other way round. Where it moves, gets wet or faces the weather makes a difference, and we’ll tell you what we are using.
Are you ARBOMaster approved?
Yes. We’re an ARBOMaster approved applicator, which is run for the Arbo sealant brand.
Why is there a gap in my brick wall?
A vertical gap in a long brick wall is usually a movement joint. It gives the wall room to move, and it should be sealed with a flexible sealant.
Is the work guaranteed?
Yes. All our work carries a one-year guarantee.
I rent my home. Can I book you?
Yes, though it’s best to check with your landlord first. Landlords are often happy for the work to be arranged.
Can you reach joints on upper floors?
That depends on how high the joints are and the ground below. Ground-floor joints are simple; for higher work, tell us about the building and we will confirm what’s needed.
What happens if it’s left?
An open joint keeps letting water into the wall with every downpour. Wet masonry is more easily damaged by frost, so the problem grows beyond the joint itself. In a flat in North Cray, failed sealant seldom stays inside your own four walls: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
Combining jobs into one visit is normally more efficient than separate visits, so it’s worth mentioning everything you’d like done. We will send you a clear quote for the lot.
What you get with us
- Neat joints and a tidy finish
- Sealant colour chosen to suit
- A 12-month guarantee on all work
- Any old sealant cut out fully, not covered over
Read what affects the cost and customer reviews.