Greater London · England
External Mastic in Oakleigh Park
Sealing brickwork movement joints, render, cladding and façade joints for homes and businesses in Oakleigh Park and across Greater London. Fully insured, ARBOMaster approved and guaranteed for a year.
- Brick movement joints where the sealant has split
- Cracked joints where brick meets render or frames
- Joints pointed up with cement by mistake
About our external mastic in Oakleigh Park
Failed sealant is cut out, the depth set with closed-cell backing rod, and the joint resealed with a low-modulus sealant made for outside. We pick a colour that sits well with the wall so the line blends in. Common call-outs are for movement joints filled with mortar instead of sealant and water getting into walls through failed joints, on render & cladding joints, façade panels and concrete & block.
Modern London flats rely on sealed movement joints and cladding joints. Period houses have different weak points, such as gutter joints, trims and the line where an extension meets the old wall.
Whatever the size of the job, it’s backed by our one-year guarantee in Oakleigh Park and across Greater London.
- Location
- Oakleigh Park (N20, N12, EN4)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
FAQs for Oakleigh Park
I let a flat near Oakleigh Park station. Can you help?
Yes, landlords and agents are among the people we work for. You can phone 0345 464 0079 or send us an email with the details for a clear quote.
Can parking be tricky for a visit in Oakleigh Park?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
Can new sealant go over the old?
No. New silicone will not bond to old silicone, and anything trapped underneath, including mould and water, stays there. We remove it all first.
Can a movement joint be filled with mortar?
No. Mortar locks the joint solid, so the wall cracks somewhere else instead. Use a flexible sealant with backing rod.
Is there a guarantee?
Yes. Every job comes with our one-year guarantee.
Is it messy?
No. We work neatly, protect the area around the joints and tidy up afterwards.
Where do you work from?
We’re a Crawley-based firm, with over 20 years’ experience. We work across South East England, London and Scotland.
Are you fully insured?
Yes. We are fully insured for domestic and commercial work.
What we can’t put right
Sealant isn’t the answer to every problem, and we will tell you before we start. It will not solve:
- Cracking across the wall rather than at a joint
- Adding movement joints to masonry that has none
- Structural movement, which needs a surveyor or engineer
If you’re not sure, just call 0345 464 0079 or send us an email and we’ll give you a straight answer before you book.
Where we work in Oakleigh Park
- Copings & trims
- Render & cladding joints
- Concrete & block
- Façade panels
- Joints between brick and frames
- Brickwork movement joints
Towns and villages near Oakleigh Park
More services for Oakleigh Park
Why act early in Oakleigh Park
A properly done movement joint is an even line in a colour that suits the wall. A rushed bead with no backing looks untidy and does not last. In London conversions, one flat’s bathroom is often above another flat’s ceiling, and a slow leak from a failed seal can end up in the flat below. Dealing with it early is far simpler for homes in Oakleigh Park.
Every job is a little different, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all make a difference.
Why us?
- White, clear, grey or another colour, product permitting
- ARBOMaster approved applicator
- Every job guaranteed for a year
- 20+ years of sealant experience
Take a look at how sealant jobs are priced and what customers say.
Walls and rooflines in Oakleigh Park
With historic houses such as Heath Hall (about 3.5 miles south) nearby, there’s older building stock in the area around Oakleigh Park as well as newer homes. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth. In terraces and conversions, gutters and walls are often shared with the neighbours, so it’s worth agreeing who is responsible before work starts.
As a London address, Oakleigh Park can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. Schools such as Queenswell Infant & Nursery School are buildings too, and larger buildings have long runs of movement joint that eventually need resealing.
Oakleigh Park is about 2 miles south-east of Barnet, in Greater London. We carry out external mastic for homes and businesses in Oakleigh Park and the surrounding area, as part of our work across Greater London. We cover 764 towns and villages across Greater London. You can also see our page for London, roughly 9 miles from Oakleigh Park.
Here we cover the N20, N12 and EN4 postcode area for external mastic. You will find streets such as High Road, Swan Lane and Green Road. Oakleigh Park sits on or near the A1000, so getting to you is simple. Neighbouring places we cover for external mastic include Whetstone (1 mile east), North Finchley (1 mile south), Woodside Park (1 mile south-west), East Barnet (1 mile north-east) and Brunswick Park (1 mile east). Larger places within reach include London (9 miles south), City of Westminster (8 miles south), Marylebone (8 miles south), Kensington (9 miles south), St Pancras (7 miles south) and Shoreditch (8 miles south-east).
Landmarks near Oakleigh Park
We work in homes and buildings around Finchley Catholic High School, Woodhouse College and Francis Skaryna Belarusian Library and Museum. Other local landmarks include Swan Lane Open Space (less than half a mile west) and Three Horseshoes pub (under half a mile north-west). The nearest railway station is Oakleigh Park station, roughly 0.8 miles north. A little further out are Finchley Memorial Hospital (1.4 miles south) and Francis Skaryna Belarusian Library and Museum (0.9 miles south-west). For a walk, there’s Barfield Allotments Nature Park and Highgate Hill.
Work for landlords, hotels and businesses
We also work for property managers and facilities teams in Oakleigh Park and across Greater London. We can quote a run of properties together, and we’re fully insured.
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
What happens on the day
We bring everything the job needs with us, so you don’t need to buy or prepare anything. After a quick look at the joints together, the area is protected and the work begins. Most jobs take a few hours for a handful of joints, longer for a whole elevation. In Oakleigh Park, flats, stairs and shared entrances are part of the routine. If the building has a concierge, managing agent or access rules, tell us when you book.
- We start by walking round the building and agreeing the joints and the access.
- 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.
- We fit closed-cell backing rod to control the depth.
- The exterior sealant is applied, tooled and checked along its length.
Preparing for the visit
- Try not to wet indoor joints just before the visit
- Tell us about access, such as stairs, a lift or high-level joints
- Keep pets and children clear of the area while we work
Ask for a quote
For a quote, call 0345 464 0079 or send us an email and tell us where the job is and what the problem looks like. You will have a clear quote before work begins.
Read more
Signs you need external mastic in Oakleigh Park
Some movement joints have been pointed up with mortar by mistake. With the joint locked solid, the movement turns into cracks elsewhere in the wall.
Keep an eye out for these signs:
- Movement joints filled with mortar instead of sealant
- Failed sealant between panels on a façade
- Weeds or debris growing in open joints
- Failed seals between different materials
In the older streets around Church of St John, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
Before booking anyone
- What product goes in the joint
- Whether all the old sealant comes out first
- The length of the guarantee
- Whether you can choose the colour
How we quote for external mastic
We quote each job individually. This is what makes a difference:
- When we can work, for business premises
- Whether old sealant or filler has to be cut out
- The type of sealant required
- Whether there’s mould to deal with
The cost reflects the work involved, not a rough estimate. That’s why we ask a few questions first and give you a clear price before work begins.
Asking for a quote
What to tell us when you ask for a quote:
- Whether it has been sealed before
- If it’s domestic, commercial or a hotel
- Photos by email, if that’s easy
- Roughly how big the job is
We don’t publish a price list, because every job is different. Instead, we send you a clear quote for your job. To arrange one, ring 0345 464 0079 or send us an email.
Should I try it myself first?
If you’re set on DIY, put the effort into preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it does not work out, we can still put it right.
A DIY attempt doesn’t rule out a professional job. We remove it and do the joint properly.