Greater London · England
External Mastic in Pinner Green
Sealing brickwork movement joints, render, cladding and façade joints for homes and businesses in Pinner Green and across Greater London. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Cracked joints where brick meets render or frames
- Joints with sealant missing in places
- Movement joints filled with mortar instead of sealant
When to call us in Pinner Green
The wrong product in a moving joint is a classic cause. A stiff, general-purpose sealant cannot cope with a joint that moves a lot, and it tears off the sides.
Keep an eye out for any of the following:
- Sealant that has lost its bond to the brick or render
- Failed seals between different materials
- Weathered mastic that no longer stretches
- Plants rooting in failed movement joints
Homes close to Christian Science Church include some older properties, and old and new materials meet at the roofline and walls, which is where sealant earns its keep.
What your quote should include
- Which sealant they’ll use, and why
- Whether VAT is included
- Whether all the old sealant comes out first
- Whether they’re fully insured
About our external mastic in Pinner Green
Many failed façade joints only get noticed once there’s a stain or a damp patch inside. We inspect them, agree which need doing and reseal with a weatherproof, flexible sealant. We work on brickwork movement joints, copings & trims and render & cladding joints, and people most often call us about failed seals between different materials and joints where the bead has come unstuck.
Outside work in London starts with access: side passages, upper floors and where to park. In Pinner Green, joints up high may need ladders or other access, which is worth talking through when you book.
Whatever the size of the job, you get the same 12-month guarantee.
- Location
- Pinner Green (HA5, HA6)
- Region
- 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
Also near Pinner Green
Other services in Pinner Green
Work for landlords, hotels and businesses
We also work for businesses, from offices to washrooms and kitchens. On commercial sites, working times can be discussed when we quote.
Whether it’s one flat or a portfolio, the work is the same standard: the old material taken out, careful preparation and a 12-month guarantee.
Outside joints around Pinner Green
London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. In terraces and conversions, gutters and walls are often shared with the neighbours, so it’s worth agreeing who is responsible before work starts.
Rented homes near Hatch End station change hands often, and outside joints that have cracked can let damp into a rental, so check them between lets. As a London address, Pinner Green can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Pinner Green is about 2 miles north-east of Ruislip, in Greater London. Our applicators cover external mastic for homes and businesses in Pinner Green and the surrounding area, as part of our work across Greater London. Our Greater London coverage runs to 764 places, and Pinner Green is one of them. We also work in London, around 15 miles away.
Our applicators cover all of the HA5 and HA6 postcode area for external mastic and the streets around it. You will find streets such as Love Lane, Tudor Road and Chapel Lane, all of which we cover. Neighbouring places we cover for external mastic include Pinner (1 mile south-east), Eastcote (1 mile south), North Harrow (2 miles south-east), Roxbourne (2 miles south) and Rayners Lane (2 miles south-east). Further out, we also cover London (15 miles south-east), City of Westminster (12 miles south-east), Marylebone (12 miles south-east), Kensington (11 miles south-east), St Pancras (13 miles south-east) and Shoreditch (14 miles east).
Local landmarks in Pinner Green
Typical jobs here are in homes near The Oddfellows Arms, UTC Heathrow and Eastcote House Gardens and the streets around them. For rail, the closest station is Hatch End station, roughly 1.3 miles north-east of the centre. Well-known places in the area include Northwood and Pinner Cottage Hospital (0.9 miles north-west) and St. George's Shopping Centre (2.6 miles south-east). Green spaces nearby include Harrow Weald Common and Horse Shoe Bay.
Pinner Green questions
Is Pinner Green in your area for external mastic?
Yes. Our work covers London and the South East, and Pinner Green is part of that. Just phone 0345 464 0079 or send us an email with a few details of the job, and we’ll give you a clear quote.
Is parking a problem for a job in Pinner Green?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. That way the visit can be planned around it.
Can you do several jobs on one visit?
Yes, and it often makes sense. Combining jobs makes good use of the visit.
How long will you be here?
As a guide, most jobs take anything from a few hours to several days, depending on the building. Bigger jobs take longer, and we’ll tell you how long to expect.
Can you work on commercial sites?
Yes. We’ve worked for hotels, offices and other businesses and we are fully insured.
Is it messy?
No. We protect the surfaces around the joints, and we tidy up before we go.
Where is Mr Mastic based?
Our base is in Crawley, West Sussex, and we cover South East England, London and all of Scotland.
Can a movement joint be filled with mortar?
No. Cement or mortar can’t stretch, so the joint stops doing its job. If it has already been filled, we can generally cut it out and reseal it.
When it isn’t the sealant
Sealant isn’t the answer to every problem, and we’d rather say so up front. Sealant won’t put right:
- Failed render or damaged cladding panels
- Cracks in the bricks or render themselves, away from the joints
- Subsidence or other structural problems
Not sure which it is? You can ring 0345 464 0079 or email us and we will tell you honestly before booking.
What we seal
- Concrete & block
- Copings & trims
- Façade panels
- Joints between brick and frames
- Render & cladding joints
- Brickwork movement joints
How it works
Once we’re on site, we check the joints match what you told us. If anything is different, we explain it before carrying on. After that, the work takes a few hours to a few days, depending on the length of joint and the access. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- Joint faces are cleaned back and primed if the sealant needs 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
- For business premises, tell us about site rules or sign-in
- Tell us about any previous sealing or DIY attempts
- Let us know about parking restrictions
Ask for a quote
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints, and email photos if that is easy.
Read more
DIY sealant or a professional job?
Overfilling a joint is a classic DIY mistake. A heavy bead looks messy and copes badly with movement, and getting the depth right matters as much as the look.
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.
Why deal with it now?
A low-modulus sealant is chosen because it moves without pulling hard at the edges. That protects surfaces like brick, render and concrete. Too stiff a sealant can pull at the edges and break them. Converted houses in London often have a bathroom above someone else’s living room, and a slow leak from a failed seal can end up in the flat below. Dealing with it early is far simpler.
Leaving a failed joint generally makes the job bigger, not smaller. If you’re unsure, phone 0345 464 0079 or send us an email and we will give you an honest view and a quote.
Why choose Mr Mastic in Pinner Green
- Colour agreed with you before work begins
- Sanitary silicone with an anti-fungal additive in wet areas
- One-year guarantee on every job
- We never seal over old sealant
See what affects the cost and our reviews.
How the job changes by surface
Concrete and blockwork
Big joints in concrete need careful depth control. We size the backing rod to the gap.
Joints between dissimilar materials
Joints where frames, sills or panels meet the wall are common leak points. We cut out the old sealant and reseal with a product suited to both surfaces.