Greater London · England
External & façade joints in Mayfair, Greater London
Problem with your movement joints in Mayfair? We remove the old material, prepare the joints and seal them properly, and the work is guaranteed for a year.
- Joints with sealant missing in places
- Hard, crazed mastic that has stopped moving
- Rigid filler in a joint that should flex
How we handle external mastic in Mayfair
For buildings in Mayfair, we reseal external joints of all kinds, from brick movement joints to cladding panels. Every joint gets the same careful preparation: clean joint faces and the right depth. If you have failed sealant between panels on a façade and old sealant gone brittle and cracked, we can put it right.
Newer London blocks are built with movement joints in brick and render, and with cladding joints sealed with mastic. 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.
Every job is covered by a one-year guarantee.
- Where
- Mayfair (W1K, W1F, W1U)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Price
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
FAQs for Mayfair
Do you cover Mayfair for external mastic?
Yes. We work across London and the South East, and Mayfair is part of that. You can call 0345 464 0079 or send us an email and tell us what needs doing.
I let a flat near Bond Street station. Can you help?
Yes. We work for landlords and letting agents as well as homeowners. Just ring 0345 464 0079 or email us with the address and what needs doing, and we will give you a clear quote.
Is it OK to fill a movement joint with cement?
No. Rigid materials can’t move with the wall, so the joint stops doing its job. Where a joint has been mortared, it can often be raked out and sealed properly.
Where are you based?
Mr Mastic is based in Crawley. Our applicators cover Mayfair.
Are you an approved applicator?
Yes. We are approved under the ARBOMaster scheme, which is run for the Arbo sealant brand.
Can you work on commercial sites?
Yes. We work in offices, washrooms, hotels and other commercial premises, as well as homes. We can talk about working times when we quote.
Do you have insurance?
Yes. We are fully insured, with over 20 years’ experience in sealant work.
What does external mastic cost?
Every job is different, so each one gets its own quote. To get one, phone 0345 464 0079 or drop us an email and let us know what needs doing and where.
When something else is needed
We’ll always be straight with you, so here’s what sealant can’t fix:
- Damp that is not coming from the joint
- Structural movement, which needs a surveyor or engineer
- Cracking across the wall rather than at a joint
If in doubt, call 0345 464 0079 or email us and we will say what we think.
What we seal
- Brickwork movement joints
- Render & cladding joints
- Copings & trims
- Joints between brick and frames
- Façade panels
- Concrete & block
Why act early in Mayfair
Resealing a run of joints in one go is generally better than patching one at a time. Joints of the same age tend to fail together and it means sorting access once. 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. Putting it right early is much less trouble for homes in Mayfair.
What you pay reflects the work, not a rough estimate. That is why we ask about the job first and give you a clear quote before any work starts.
Why us?
- Colour agreed with you before we start
- More than 20 years in sealant work
- Tidy, careful work
- Rated 4.9 stars on Google
See our cost guide and our reviews.
What happens on the day
Our applicators work methodically: protection first, then preparation, sealing and a tidy-up. For most jobs that takes a few hours to a few days, depending on the length of joint and the access and we leave things clean and tidy. In a London area like Mayfair, 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.
- Primer is applied wherever the sealant needs it.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
How to prepare
- Mention any sign-in or site rules at work premises
- Let us know about earlier repairs to the joints
- Move anything stored near the joints
Getting a quote
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is.
Read more
Places near Mayfair
More services for Mayfair
What external mastic looks like in Mayfair
The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Historic houses like Handel Hendrix House (about 0.2 miles north) are a reminder that the area around Mayfair has older buildings as well as new. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth.
For landlords with property near Bond Street station, failed wall and movement joints let damp in, so they’re worth checking between tenancies. Schools such as LITE Regal International School are buildings too, and its movement joints, gutters and trims need looking after like any other building’s.
Mayfair is about 1 mile south-east of City of Westminster, in Greater London. Jobs in Mayfair get the same care as everywhere else we work: old sealant removed completely, careful preparation and a one-year guarantee. Our area takes in 764 places across Greater London, large and small.
Our applicators cover all of the W1K, W1F and W1U postcode area for external mastic. Whether your property is on Park Lane, Bruton Lane and Market Mews or a nearby road, our applicators can take on the job. Main roads around Mayfair include the A4201 and A4202. Neighbouring places we cover for external mastic include Burlington Estate (1 mile east), City of Westminster (1 mile north-west), Marylebone (1 mile north), St James's (1 mile east) and Chinatown (1 mile east). We also work in nearby towns such as Shoreditch (3 miles east), Walthamstow (7 miles north-east), Hoxton (3 miles north-east), Whitechapel (3 miles east), Hampstead (3 miles north-west) and Ruislip (12 miles west).
What’s near Mayfair
Locally, jobs take us to homes and businesses close to Royal College of Nursing Library & Museum, Coach and Horses pub and St George's Church of England Primary School, among other places. You’ll also find Green Park (0.5 miles south) and The St Marylebone CofE School (0.8 miles north). There’s a railway station in Mayfair itself: Bond Street station. Other landmarks nearby include Montfichet's Tower (2 miles east) and London Eye Hospital (0.5 miles north). Open spaces near Mayfair include Ludgate Hill and St. James's Park Lake.
What affects the cost of external mastic
We quote each job individually. This is what makes a difference:
- How much there is to do
- How many areas need sealing
- How much old sealant there is and how hard it is to remove
- When we can work, for business premises
A failed joint rarely gets cheaper to fix by waiting, as water and mould keep getting in. If you are not sure whether it needs doing, ring 0345 464 0079 or drop us an email for an honest opinion and a quote.
What we need to know
Photos by email are helpful but not essential. Please mention:
- How many joints, rooms or windows are involved
- Pictures of the joints, sent by email
- The address or postcode of the job
- Any access issues, like height or stairs
For a quote, ring 0345 464 0079 or drop us an email and tell us where the job is and what the problem looks like. We’ll give you a clear quote before any work starts.
For landlords and businesses
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.
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance that we can handle for you.
Looking after it afterwards
So the new joints stay in good condition:
- Have failed joints looked at early
- Keep movement joints as flexible joints, not mortar
- Look over the joints every year, ideally after winter
- Fix overflowing gutters above sealed joints
Keep pressure washers away from the sealant. A strong jet can damage the edges of the bead.
Once a joint can’t move, the wall finds another way, often as cracks near the joint. Resealing it early helps prevent that.
When to call us in Mayfair
If plants are growing out of a joint, the sealant has generally failed or was never there. Roots and dirt hold water against the wall and speed up the damage.
The most common problems we see are:
- Movement joints with cracked, split or missing sealant
- Damp patches traced to an open external joint
- Failed seals between different materials
- Failed sealant between panels on a façade
For an older house near a landmark such as Grosvenor Chapel, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
Questions to ask before you book
- Who does the work, and how experienced they are
- Whether they seal over old material or remove it
- What product goes in the joint
- What guarantee comes with the work