Greater London · England
External & façade joints in Arnos Grove, Greater London
External mastic for Arnos Grove and the surrounding area: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Leaking joints around cladding and façade panels
- Gaps where render, brick and frames meet
- Damp patches traced to an open external joint
Landlords, agents and businesses in Arnos Grove
If you manage several properties in or around Arnos Grove, jobs at different addresses can be quoted together. Send us the addresses and the work at each.
We work for letting agents and landlords as well as homeowners. Sealant work between tenants is a simple way to keep a property in good order.
How we handle external mastic in Arnos Grove
Low-level joints can usually be done from the ground. For joints higher up, give us some details of the building and we will confirm what access is needed. If you have moss and dirt in joints with no sealant left and joints where the bead has come unstuck, we can put it right, on copings & trims, concrete & block and render & cladding joints alike.
Working on the outside of a London home means planning access: shared paths, upper floors and parking. For a home in Arnos Grove, tell us how high the joints are and how to reach the back of the building.
Every job comes with our one-year guarantee.
- Place
- Arnos Grove (N11, N14, N13)
- Region
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Places near Arnos Grove
What else we do in Arnos Grove
When to call us in Arnos Grove
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.
The problems people normally mention when they call are:
- Failed seals between different materials
- Plants rooting in failed movement joints
- Leaking joints around cladding and façade panels
- Joints where the bead has come unstuck
Letting a property close to New Southgate station? Then split movement joints are easy to miss on a rental until damp shows inside.
What your quote should include
- When the joint can take water or movement
- What happens if the job turns out different
- Whether they’re fully insured
- How long the guarantee is
Arnos Grove questions
Do you work for landlords with property near New Southgate station?
Yes. We work for landlords and letting agents as well as householders, and several properties can go on one quote. Just call 0345 464 0079 or send us an email with the address and what needs doing, and we will send you a clear quote.
Do you cover Arnos Grove for external mastic?
Yes. Our work covers London and the South East, and Arnos Grove is part of that. You can call 0345 464 0079 or drop us an email and let us know what needs doing, and we will send you a clear quote.
Can you do several jobs on one visit?
Yes. Tell us about everything you’d like done and you’ll get one quote.
Is there any odour?
Some sealants have a smell while they cure, which fades as it sets. Ventilation helps.
What does external mastic cost?
Size, access and the old material all affect the cost. Call for a quick quote.
Will the old sealant be removed?
Yes, always, and completely. New silicone does not stick to old silicone, so the joint is cleaned back first.
Do you guarantee your work?
Yes. All our work carries a one-year guarantee.
Do you have insurance?
Yes. We’re fully insured.
Outside joints around Arnos Grove
London terraces and converted houses often share gutters, downpipes and walls, so it’s worth agreeing who is responsible before work starts. The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
If you live in an older home near Syro-Malabar Catholic Church of London, an extension built onto an older house moves differently, and the joint between them takes the strain. For site and facilities teams at buildings such as Bowes Primary School, larger buildings have long runs of movement joint that eventually need resealing.
Arnos Grove is about 3 miles north-east of Finchley, in Greater London. Our applicators cover external mastic for homes and businesses in Arnos Grove and nearby, as part of our work across Greater London. 764 places in Greater London are on our list, from the larger towns to small villages. London is on our list too, about 8 miles from Arnos Grove.
Work in N11, N14 and N13 works the same way as everywhere else we cover. We cover properties on Oak Lane, High Road and York Road and the roads around them. Arnos Grove sits on or near the A109 and A1004. Close by, we work in New Southgate (1 mile west), Bounds Green (1 mile south), Southgate (1 mile north), Palmers Green (1 mile east) and Oakthorpe Park (1 mile east). Further out, we also cover London (8 miles south), City of Westminster (7 miles south), Marylebone (7 miles south), Kensington (9 miles south), St Pancras (6 miles south) and Shoreditch (7 miles south).
Local landmarks in Arnos Grove
We work in homes and buildings around The Ranelagh pub, Broomfield School and Broomfield Park and the streets around them. For rail, the closest station is New Southgate station, roughly 0.6 miles west. Nearby you will also find Broomfield House Museum (0.5 miles east) and The Mall Wood Green (1.7 miles south-east). Green spaces nearby include Highgate Hill and Darland's Lake.
When something else is needed
New sealant can’t fix everything, and we’d rather say so up front. Sealant won’t put right:
- Structural movement, which needs a surveyor or engineer
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
- Walls that need new movement joints cut into them
If you are not sure, just call 0345 464 0079 or email us and we’ll give you a straight answer.
What we seal
- Concrete & block
- Joints between brick and frames
- Copings & trims
- Render & cladding joints
- Façade panels
- Brickwork movement joints
Aftercare tips
Good habits help new joints last longer. A few tips:
- Check the sealant is paintable before painting near it
- Tell anyone working on the walls about the movement joints
- Get split or bare joints resealed while the damage is small
- Make sure movement joints aren’t pointed over
Avoid pressure-washing straight into the joints. A strong jet can damage the edges of the bead and let water in behind.
If you can see gaps, plants or bare sections in a joint, have it checked. Earlier resealing means a smaller job and a better result.
What affects the cost of external mastic
Jobs vary more than people expect. The main factors:
- Which sealant suits the joint
- Access and height
- Working hours on commercial sites
- The amount of work
Combining jobs into one visit generally makes better use of the time than several visits. We’ll give you a clear quote for the lot.
What we need to know
There’s no need for technical detail. It helps if you can tell us:
- What the problem is, such as mould, gaps, leaks or cracking
- Where the property is
- If someone has resealed it before
- A few photos by email, if you can
There’s no standard price list, because every job is different. Instead, we give you a clear quote for your job. To arrange one, call 0345 464 0079 or email us.
What happens on the day
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 a few hours to a few days, depending on the length of joint and the access. For a job in Arnos Grove, parking and access are the things to plan: tell us about permits, visitor bays or off-street space, which floor we’re working on and whether there’s a lift.
- Each joint is checked and the colour of the new sealant agreed.
- 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.
- We gun in low-modulus sealant and tool it neatly.
Getting ready for the visit
- Mention if the joints have been sealed before
- Tell us if parking is tricky
- Let us know about stairs, lifts or work at height
Getting a quote
We quote each job on its own. Just ring 0345 464 0079 or drop us an email with the details.
Read more
Surface by surface
Copings and trims
Joints in copings, parapets and trims are exposed to the worst of the weather. Each is resealed with a weatherproof, flexible sealant.
Render joints
Render has movement joints and stop beads that need sealing. We reseal them with a flexible exterior sealant that suits the render colour.