Greater London · England
External & façade joints in Duckett's Green, Greater London
Sealing brickwork movement joints, render, cladding and façade joints for Duckett's Green, backed by a one-year guarantee. Ask us for a quote.
- Hard, crazed mastic that has stopped moving
- Sealant pulling away from one side of the joint
- Cracked joints where brick meets render or frames
Your questions about external mastic in Duckett's Green
Can you do external mastic in Duckett's Green?
Yes. We work across London and the South East, and Duckett's Green is part of that. You can ring 0345 464 0079 or email us and let us know what needs doing.
Can you help a landlord with a rental near Hornsey station?
Yes, landlords and agents are among the people we work for. You can call 0345 464 0079 or drop us an email with the details for a clear quote.
Will there be a smell?
There can be a smell while the sealant cures. Opening a window helps.
Is it messy?
Not at all. The area is protected while we work and cleaned up afterwards.
Can you do several jobs on one visit?
Yes, and it often makes sense. Doing several areas at once is normally more efficient, so mention them when you ask for a quote.
Is there a guarantee?
Yes, always. Each job is guaranteed for twelve months, large or small.
Can a movement joint be filled with mortar?
No, not if it’s a movement joint. Pointing it stops it working, and the wall may crack nearby. We’ll reseal it with a flexible sealant.
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 will get a clear quote before we start.
External mastic for homes and businesses in Duckett's Green
Getting the depth right is half the job. Backing rod controls how deep the sealant goes and keeps it off the back of the joint, leaving it bonded to two faces so it can move with the wall. If you have joints pointed up with cement by mistake and gaps where render, brick and frames meet, we can help.
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. In a converted house in Duckett's Green, it’s worth checking who is responsible for the outside before booking.
The work is covered for a year after we finish. If anything isn’t right with it, phone 0345 464 0079 or drop us an email.
- Location
- Duckett's Green (N15, N22, N8)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before work begins
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Signs you need external mastic in Duckett's Green
Buildings move more than people expect. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. All of that ends up in the joint sealant.
Look out for these signs:
- Joints with sealant missing in places
- Movement joints filled with mortar instead of sealant
- Sealant pulling away from one side of the joint
- Leaking joints around cladding and façade panels
If you live in an older home near Christ Church, older walls, gutters and the joints where extensions meet them need a flexible sealant.
What your quote should include
- What happens if the job turns out different
- How much experience the applicator has
- Which sealant they’ll use, and why
- Whether all the old sealant comes out first
How it works
Most of a good job is in the preparation, and we don’t rush it. Joints are cleaned back and dried before anything new goes in. In total, it normally takes anything from a few hours to several days, depending on the building. In a London area like Duckett's Green, the main things to plan are parking and access: tell us about permits, visitor bays or off-street space, which floor we are working on and whether there’s a lift.
- We look at every joint and agree a colour to suit the wall.
- Failed sealant is removed back to clean, sound faces.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- We prime the faces where required.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Before we arrive
- Mention if the joints have been sealed before
- Tell us about any water getting in
- For business premises, tell us about site rules or sign-in
How to get a quote
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is. When it suits you, phone 0345 464 0079 or send us an email.
Read more
Aftercare tips
Looking after new joints is easy, and it makes a real difference:
- Point out the joints to other trades
- Check external joints each spring
- Clear growth from the base of walls and joints
- Deal with leaking gutters that soak the joints below
Have a quick look at the joints each spring. Splits, gaps at the edges or plants in the joint are early warning signs.
Leave a failed movement joint and water keeps getting into the wall. Over time it can mean damp inside, stained render or frost-damaged brick.
Also near Duckett's Green
More services for Duckett's Green
Different surfaces, different methods
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.
Render joints
Cracks along render joints let water in behind the coat. Resealing the joints early keeps water out.
Quotes for external mastic in Duckett's Green
For a quick quote, just ask. The main things that affect it are:
- The product the joint needs
- How easy the joints are to reach
- Whether there’s mould to deal with
- When we can work, for business premises
Combining jobs into one visit generally makes better use of the time than several visits, so tell us about everything that needs sealing. You will get one clear quote for the whole job.
What we need to know
Before you ask for a quote, have a think about:
- How many joints, rooms or windows are involved
- Photos by email, if that is easy
- How we’d reach the joints
- Where the property is
For a quote, call 0345 464 0079 or send us an email with the location and a short description of the problem. You will have a clear quote before any work starts.
DIY sealant or a professional job?
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it peels away and traps moisture behind it. All the old material has to come out first.
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
Honest limits
We’ll always be straight with you, so here’s what sealant can’t fix:
- Movement that’s more than a sealant joint can take
- Cracks in the bricks or render themselves, away from the joints
- Damp that is not coming from the joint
Not sure which it is? You can ring 0345 464 0079 or drop us an email and we will tell you honestly.
Surfaces we seal
- Render & cladding joints
- Joints between brick and frames
- Brickwork movement joints
- Copings & trims
- Concrete & block
- Façade panels
What external mastic looks like in Duckett's Green
Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. London terraces and converted houses often share gutters, downpipes and walls, so check who is responsible for the outside before booking.
As a London address, Duckett's Green can be tricky for parking: let us know about parking bays, permits or a driveway. If you look after a building such as St John Vianney RC Primary School, larger buildings have long runs of movement joint that eventually need resealing.
Duckett's Green is about 3 miles north of Highbury, in Greater London. Jobs in Duckett's Green get the same care as everywhere else we work: old sealant removed completely, careful preparation and a 12-month guarantee. Duckett's Green is one of 764 towns and villages in Greater London we cover. There’s also a page for London, roughly 6 miles from Duckett's Green.
All of N15, N22 and N8 is covered for external mastic, from the main roads to the quietest streets. Streets in the area include Bury Road, Mark Road and Frome Road. Duckett's Green is on the A1080, so it’s easy for us to get to. Other places close to Duckett's Green include West Green (1 mile south-east), Harringay (1 mile south), St Ann's (1 mile south-east), Broadwater Farm (1 mile north-east) and Tottenham Green (1 mile east). We also work in nearby towns such as London (6 miles south), City of Westminster (6 miles south-west), Marylebone (5 miles south-west), Kensington (8 miles south-west), St Pancras (4 miles south) and Shoreditch (4 miles south).
What’s near Duckett's Green
Typical jobs here are in homes near Moselle Upper School, Ducketts Common and The Queens Head pub. Duckett's Green’s nearest station is Hornsey station, roughly 0.7 miles west of the centre. A little further out are Greentrees Hospital (1.5 miles north) and Markfield Beam Engine and Museum (1.6 miles east). Not far away are Hollow Pond and Railway Fields.