Greater London · England
External & façade joints in Winchmore Hill, Greater London
External mastic for Winchmore Hill, by sealant specialists with 20+ years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Movement joints filled with mortar instead of sealant
- Rain getting behind render or cladding at a joint
- Weathered mastic that no longer stretches
Winchmore Hill: your questions answered
I let a flat near Winchmore Hill station. Can you help?
Yes, rental work is part of what we do. You can ring 0345 464 0079 or send us an email with the address and a few details, and we’ll give you a fixed price before any work starts.
Can you do external mastic in Winchmore Hill?
Yes. We work across London and the South East, and Winchmore Hill is part of that. Just phone 0345 464 0079 or send us an email with a few details of the job, and we will give you a clear price.
What is backing rod for?
That’s backing rod, a closed-cell foam. It stops the sealant going in too deep and bonding to three sides so it can flex with the joint.
Can a movement joint be filled with mortar?
No. Mortar locks the joint solid, so the wall cracks somewhere else instead. It needs a flexible sealant over backing rod.
What does external mastic cost?
It depends on the job, so we quote each one individually. To get one, phone 0345 464 0079 or send us an email with a short description of the job.
When will the joints need doing again?
That varies with the weather the wall faces, how much it moves and the sealant used. Sealant is a maintenance item, so check the joints once a year.
Do you remove the old sealant?
Yes. All of the old material is cut out and the joint cleaned before resealing.
What should I tell you?
Only a few details: where it is, what you’ve noticed and how we reach it. Then ring 0345 464 0079 or send us an email.
External mastic in Winchmore Hill
External mastic is a job where short cuts show quickly. New sealant over old, joints packed with mortar and beads with no backing rarely last long. We take the old material out and do it properly. We’re often asked to deal with plants rooting in failed movement joints and old sealant gone brittle and cracked, on brickwork movement joints, façade panels and copings & trims.
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, and both kinds of building are found across London.
We stand behind the work with a one-year guarantee.
- Place
- Winchmore Hill (N21, N13, N9)
- Region
- Greater London
- Cover
- 12 months on all our work
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
Winchmore Hill buildings and the weather
With historic houses such as Bruce Castle (about 2.6 miles south-east) nearby, there’s older building stock in the area around Winchmore Hill as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. In terraces and conversions, gutters and walls are often shared with the neighbours, so check who is responsible for the outside before booking.
For an older house near a landmark such as Holy Trinity, an extension built onto an older house moves differently, and the joint between them takes the strain. As a London address, Winchmore Hill can be tricky for parking: let us know about parking bays, permits or a driveway.
Winchmore Hill is about 2 miles north-west of Edmonton, in Greater London. Our applicators cover external mastic for homes and businesses in Winchmore Hill and nearby. Our Greater London coverage runs to 764 places, and Winchmore Hill is one of them. We also work in London, around 9 miles away.
Here we cover the N21, N13 and N9 postcode area for external mastic. Whether your property is on Farm Road, Arlow Road and Hurst Road or a nearby road, we can help. Other places close to Winchmore Hill include Bush Hill (1 mile north-east), Bush Hill Park (1 mile north-east), Enfield (1 mile north-east), Enfield Chase (2 miles north) and Edmonton (2 miles south-east). Within a short drive, we also cover London (9 miles south), City of Westminster (9 miles south), Marylebone (8 miles south), Kensington (10 miles south-west), St Pancras (7 miles south) and Shoreditch (8 miles south).
Local landmarks in Winchmore Hill
In Winchmore Hill, that means homes and buildings near Winchmore School, Keble Preparatory School and The Kings Head pub. Winchmore Hill has its own railway station: Winchmore Hill station. Nearby you will also find Museum of Enfield (1.4 miles north-east) and Edmonton Green Shopping Centre (1.9 miles east). Open spaces near Winchmore Hill include Darland's Lake and Barfield Allotments Nature Park.
What affects the quote in Winchmore Hill
Call for a quick quote. What matters most is:
- Whether old sealant or filler has to be cut out
- The number and length of the joints
- Which sealant suits the joint
- Whether there’s mould to deal with
Doing several joints on one visit is generally more efficient than separate visits, so it’s worth mentioning everything you’d like done. We’ll give you a clear price for the lot.
Helping us quote
What to tell us when you ask for a quote:
- The type of property
- Where the property is
- How many joints, rooms or windows are involved
- Photos by email, if that’s easy
Getting a quote is simple: let us know the job and the location and its rough size. A few photos by email make the job easier to understand.
Places near Winchmore Hill
Other services in Winchmore Hill
Can I do it myself?
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs call for the right materials, safe access and experience.
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and does not move well, and getting the depth right matters as much as the look.
Why it’s worth doing now in Winchmore Hill
Water gets in through a failed movement joint and can run behind render or cladding. Dealing with it early keeps the repair to the joint, rather than the wall around it. In a flat in Winchmore Hill, 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.
A failed joint rarely gets cheaper to fix by waiting. If you’re unsure, phone 0345 464 0079 or email us and we will give you an honest view and a quote.
Why us?
- Approved under the ARBOMaster scheme
- 180+ five-star Google reviews
- Neat joints and a tidy finish
- We agree the colour with you first
Read what affects the cost and what customers say.
When something else is needed
New sealant can’t fix everything, and we’d rather say so up front. Sealant won’t put right:
- Adding movement joints to masonry that has none
- Failed render or damaged cladding panels
- Cracked brickwork or render that needs a builder or plasterer
If you’re not sure, just phone 0345 464 0079 or drop us an email and we’ll give you a straight answer.
Where we work in Winchmore Hill
- Copings & trims
- Brickwork movement joints
- Render & cladding joints
- Concrete & block
- Joints between brick and frames
- Façade panels
Signs you need external mastic in Winchmore Hill
A lot of failed joints come down to preparation: joint faces that were dusty or damp, unprimed where they needed it, or still carrying old sealant. The new sealant then lets go long before it should.
If you can see any of these, it’s time to have the joints looked at:
- Sealant that has lost its bond to the brick or render
- Rain getting behind render or cladding at a joint
- Failed sealant between panels on a façade
- Brick movement joints where the sealant has split
Managing a site like St. Paul's School? Then larger buildings have long runs of movement joint that eventually need resealing.
What your quote should include
- What happens if the job turns out different
- Are they insured?
- Is VAT in the price?
- How long to leave it before use
Keeping the joints in good condition
No joint lasts for ever, but care makes a real difference. A few tips:
- Deal with leaking gutters that soak the joints below
- Never let anyone fill a movement joint with mortar
- Wash walls gently around the sealant
- Get split or bare joints resealed while the damage is small
Do not let soil, plants or ivy build up against the new joints. Damp material against the sealant shortens its life.
Once a joint cannot move, the wall finds another way, often as cracks near the joint. Resealing it early helps prevent that.
How the visit works
Before we leave, we go over the finished joints with you and explain the cure time. The work normally takes a few hours for a handful of joints, longer for a whole elevation, depending on the amount of work. In a London area like Winchmore Hill, 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.
- Each joint is checked and the colour of the new sealant agreed.
- Failed sealant is removed back to clean, sound faces.
- Backing rod goes in so the sealant can stretch between the two faces.
- We prime the faces where required.
- We gun in low-modulus sealant and tool it neatly.
How to prepare
- Move anything stored near the joints
- Try not to wet indoor joints just before the visit
- Tell us about any previous sealing or DIY attempts
How to get a quote
For a quick quote, get us on the phone, or send an email if you’d rather. Tell us about the joints that need doing and we’ll talk you through the work and give you a clear quote.