Greater London · England
External & façade joints in St Margarets, Greater London
Sealing brickwork movement joints, render, cladding and façade joints for homes and businesses in St Margarets and across Greater London. Fully insured, ARBOMaster approved and guaranteed for a year.
- Gaps where render, brick and frames meet
- Weeds or debris growing in open joints
- Damp patches traced to an open external joint
When to call us in St Margarets
Some movement joints have been pointed up with mortar by mistake. The joint cannot move, so the wall cracks somewhere else instead.
Any of these means the joints need attention:
- Movement joints with cracked, split or missing sealant
- Weeds or debris growing in open joints
- Sealant pulling away from one side of the joint
- Hard, crazed mastic that has stopped moving
Richmond House, about 1 mile south, is one of the historic houses in the wider area around St Margarets.
Comparing quotes
- What insurance they hold
- Is VAT in the price?
- How hidden problems are handled
- What guarantee comes with the work
External mastic in St Margarets, done properly
We are ARBOMaster approved applicators, and each external joint gets a sealant suited to it. Porous or awkward surfaces are primed where the sealant needs it and we use one wherever it does. We are often asked to deal with joints where the bead has come unstuck and gaps where render, brick and frames meet, on brickwork movement joints, façade panels and joints between brick and frames.
Outside work in London starts with access: side passages, upper floors and where to park. In St Margarets, joints up high may need ladders or other access, which is worth talking through when you book.
We stand behind the work with a 12-month guarantee.
- Where
- St Margarets (TW1, TW7, TW9)
- Region
- Greater London
- Guarantee
- One year on every job
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
What happens on the day
When we get to you, we check the joints match what you told us. If anything is different, we explain it before carrying on. Most jobs then take a few hours for a handful of joints, longer for a whole elevation. In a London area like St Margarets, the main things to plan are parking and access: let us know about parking, the floor we’ll be working on and any lift or shared entrance.
- Each joint is checked and the colour of the new sealant agreed.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- We prime the faces where required.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Preparing for the visit
- Tell us about any previous sealing or DIY attempts
- For indoor joints, keep the area dry beforehand if you can
- Let us know if you’ve seen damp or leaks
Ask for a quote
If you’re in St Margarets and need external mastic, call 0345 464 0079 or send us an email. A short description of the job and where it is helps us quote, and we will agree the price before any work begins.
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Leave it or put it right?
Low-modulus sealants stretch easily, so they put less strain on the joint edges. That protects surfaces like brick, render and concrete. Too stiff a sealant can pull at the edges and break them. In a flat in St Margarets, failed sealant seldom stays inside your own four walls: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
Combining jobs into one visit is usually more efficient than separate visits, so tell us about everything that needs sealing. You’ll get one clear quote for the whole job.
Why book with us
- We never seal over old sealant
- 12-month guarantee on every job
- Colour picked to suit the job
- We leave the area clean and tidy
Read what affects the cost or our reviews.
Surface by surface
Joints between dissimilar materials
Where a frame or panel meets masonry, water often finds a way in. The old joint is removed and a sealant that bonds to both sides goes in.
Concrete and blockwork
Big joints in concrete need careful depth control. Backing rod sized to the joint sets it and keep the sealant to the right depth.
Quotes for external mastic in St Margarets
There’s no set price list, because jobs vary so much. The quote depends on:
- The product the joint needs
- Working hours on commercial sites
- Access and height
- The old material and how stubborn it is
No two jobs are quite the same, so each one gets its own quote. Size, access and the product the joint needs all play a part, and we will explain the quote if you ask.
What to tell us for a quote
Before you ask for a quote, have a think about:
- Roughly how big the job is
- What the problem is, such as mould, gaps, leaks or cracking
- The type of property
- If someone has resealed it before
To get a quote, phone 0345 464 0079 or email us with the location and a short description of the problem. We will give you a clear price before any work starts.
St Margarets questions
Is parking a problem for a job in St Margarets?
In much of London, parking needs planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
I let a flat near St Margarets (London) station. Can you help?
Yes. We work for landlords and agents as well as householders, and several properties can be quoted together. Just phone 0345 464 0079 or drop us an email with the address and what needs doing, and we will send you a clear quote.
Can you seal joints between two different materials?
Yes. Different materials move at different rates, so a flexible sealant is needed where they meet. The sealant is matched to both sides.
How long before the joint can be used?
That depends on the sealant used, so follow the cure time we give you.
Is it OK to seal over old sealant?
No, it will not last. It may look fine at first, but the new layer lifts away from the old one. The old sealant has to come out completely.
Do you have insurance?
Yes. Full insurance covers our work.
Do you take out the old sealant first?
Yes. All of the old material is cut out and the joint cleaned.
What do you need from me for a quote?
Let us know what needs doing and where, with photos by email if possible. If we need more, we will ask.
When something else is needed
It helps to know what we can’t do too:
- Subsidence or other structural problems
- Cutting new joints into brickwork, which is building work rather than sealant work
- Rising or penetrating damp from elsewhere in the wall
Not sure which it is? You can phone 0345 464 0079 or drop us an email and we’ll tell you honestly.
Surfaces we seal
- Brickwork movement joints
- Copings & trims
- Joints between brick and frames
- Façade panels
- Render & cladding joints
- Concrete & block
Nearby places to St Margarets
Also in St Margarets
DIY versus a professional finish
If you’ve already had a go yourself, that is fine. We cut it out and start again.
What a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions.
Walls and rooflines in St Margarets
London terraces and converted houses often share gutters, downpipes and walls, so check who is responsible for the outside before booking. With historic houses such as Richmond House (about 1 mile south) nearby, there’s older building stock in the area around St Margarets as well as newer homes. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth.
If you look after a building such as Worple Primary School, movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. Letting a property close to St Margarets (London) station? Then split movement joints are easy to miss on a rental until damp shows inside.
St Margarets is about 1 mile north-east of Twickenham, in Greater London. For external mastic in and around St Margarets, please ring 0345 464 0079 or send us an email for a quick quote. We are based in Crawley and cover Greater London. St Margarets is one of 764 places in Greater London we cover. You can also see our page for London, about 10 miles away.
Jobs for external mastic in TW1, TW7 and TW9 is quoted and booked the same way as anywhere else. Whether your property is on Eve Road, Park Road and Crown Road or anywhere close by, we can help. You will find St Margarets on the A316 and A3004, so it’s easy for us to get to. Close by, we work in Isleworth (1 mile north-west), Richmond (1 mile east), Ivybridge (1 mile west), Eel Pie Island (1 mile south) and Twickenham (1 mile south-west). Larger places within reach include London (10 miles east), City of Westminster (8 miles north-east), Marylebone (8 miles north-east), Kensington (6 miles north-east), St Pancras (10 miles north-east) and Shoreditch (11 miles north-east).
Near you in St Margarets
Around St Margarets, our work takes us to homes and buildings near Richmond Green, Orleans Park School and The Turks Head pub. St Margarets has its own railway station: St Margarets (London) station. Well-known places in the area include South Middlesex Hospital (0.8 miles west) and Eel Pie Island Museum (0.8 miles south). Green spaces nearby include Richmond Hill and Ham Lands.