Greater London · England
External & façade joints in Sanderstead, Greater London
We cover Sanderstead for sealing brickwork movement joints, render, cladding and façade joints. Old material cut out, joints cleaned and sealed neatly and every job guaranteed for a year.
- Plants rooting in failed movement joints
- Leaking joints around cladding and façade panels
- Joints pointed up with cement by mistake
External mastic in Sanderstead
A movement joint is only as good as its depth. Backing rod controls how deep the sealant goes and keeps it off the back of the joint, so it bonds to the two sides only and can stretch. If you’re dealing with gaps where render, brick and frames meet and moss and dirt in joints with no sealant left, we can put it right.
Outside work in London starts with access: side passages, upper floors and where to park. In Sanderstead, joints up high may need ladders or other access, which is worth talking through when you book.
A 12-month guarantee comes with the work, just as it does everywhere we cover.
- Place
- Sanderstead (CR2, CR8)
- Region
- Greater London
- Cover
- 12 months on all our work
- Quote
- A clear price before work begins
- Call
- 0345 464 0079
- Updated
- 26 October 2026
How we quote for external mastic
The price is agreed before any work begins. It’s based on:
- Any working-time requirements on site
- The type of sealant required
- Any mould that needs treating
- The amount of work
No two jobs are quite the same, 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, and we will explain the quote if you ask.
Helping us quote
The more you tell us, the more accurate the quote. When you get in contact, it helps to mention:
- A few pictures by email, if you can
- How we’d reach the joints
- Where the job is, and your postcode
- Roughly how big the job is
We quote each job on its own, so start by telling us what you need. Just phone 0345 464 0079 or send us an email with the details and send photos if you have them.
Towns and villages near Sanderstead
More services for Sanderstead
External mastic in Sanderstead: local notes
Historic houses like Addington Palace (about 2.3 miles north-east) are a reminder that the area around Sanderstead has older buildings as well as new. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Sanderstead is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. If you look after a building such as Gresham Primary School, its movement joints, gutters and trims need looking after like any other building’s.
Sanderstead is about 2 miles east of Purley, in Greater London. Jobs in Sanderstead get the same care as everywhere else we work: old sealant removed completely, careful preparation and a one-year guarantee. Sanderstead is one of 764 towns and villages in Greater London we cover. You can also see our page for London, about 11 miles away.
Our applicators cover all of CR2 and CR8 for external mastic and the streets around it. If you need external mastic at a property on Hyde Road, Brian Avenue and Sundown Avenue or anywhere close by, we can help. Sanderstead sits on or near the A2022. Other places close to Sanderstead include Riddlesdown (1 mile south-west), Kenley (1 mile south-west), South Croydon (1 mile north-west), Selsdon (1 mile north-east) and Hamsey Green (1 mile south-east). Further out, we also cover London (11 miles north), City of Westminster (13 miles north), Marylebone (13 miles north), Kensington (12 miles north-west), St Pancras (13 miles north) and Shoreditch (13 miles north).
What’s near Sanderstead
Around Sanderstead, our work takes us to homes and buildings near Selsdon Park Hotel, Littleheath Woods and Riddlesdown Collegiate, among other places. The nearest railway station is Riddlesdown station, roughly 0.8 miles west. Nearby you’ll also find Purley War Memorial Hospital (1.4 miles west) and Croydon Airport Visitor Centre (2.1 miles north-west). The countryside around Sanderstead includes Duppas Hill and Foxley Wood.
Landlords, agents and businesses in Sanderstead
Housing providers, facilities teams and property managers book us too in Sanderstead and across Greater London. Several sites can go on one quote.
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements.
Can I do it myself?
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it lifts and traps water and mould underneath. All the old material has to come out first.
A DIY attempt does not rule out a professional job. We remove it and do the joint properly, so just mention it when you contact us.
Do you need external mastic in Sanderstead?
Joints sealed without backing rod, or far too deep, rarely last. Sealant bonded to three sides has nowhere to go and tears as soon as the joint widens.
The most common problems we see are:
- Sealant that has lost its bond to the brick or render
- Rigid filler in a joint that should flex
- Brick movement joints where the sealant has split
- Old sealant gone brittle and cracked
Homes close to Church of All Saints include some older properties, and the joints between older walls, newer extensions and the roofline need a sealant that can move.
What your quote should include
- What the quote includes, VAT included or not
- When the joint can take water or movement
- How much experience the applicator has
- What happens if the job turns out different
How it works
The work is kept neat and contained to the joints we’re treating, so you can carry on as normal. Expect the work to take a few hours to a few days, depending on the length of joint and the access, and we tell you how long to leave it before we go. In Sanderstead, as in most of London, parking needs a little planning. It helps if you can point us to a visitor permit or a bay close to the door.
- 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.
- Primer is applied wherever the sealant needs it.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Preparing for the visit
- On commercial sites, let us know about site rules
- Keep children and pets away from the work area
- Let us know about stairs, lifts or work at height
Ask for a quote
For external mastic in Sanderstead, ring 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and you will get a clear quote before we start.
Related advice
What the job involves on each surface
Cladding and façade panels
If the façade has a specified sealant, that is what we use or an approved alternative. Tell us what the building has when you get in touch.
Render joints
Rendered walls have joints at beads, openings and changes of material. They’re resealed in a sealant that suits the render.
Why act early in Sanderstead
Pointing a movement joint with mortar might seem a neat fix, but it locks the joint solid. The wall then cracks somewhere else. A flexible sealant over backing rod is what the joint needs. In a London flat, a failed joint rarely stays your problem alone: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
We don’t show prices on the website, because the cost depends so much on the job itself. Call for a quick quote and we will talk you through it.
What you get with us
- A sealant colour to suit the surroundings
- A choice of colours where the product allows
- Quality sealants from Arbo and Everbuild
- We leave the area clean and tidy
Sanderstead: your questions answered
I let a flat near Riddlesdown station. Can you help?
Yes, rental work is part of what we do. Just ring 0345 464 0079 or send us an email and tell us about the property, and we will give you a clear quote.
Can parking be tricky for a visit in Sanderstead?
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.
Where do you work from?
Our base is in Crawley, and we cover South East England, London and all of Scotland.
Do you work in Sanderstead?
Yes. From our base in Crawley, we cover South East England, London and all of Scotland.
What sealant do you use?
Quality sealants from brands including Arbo and Everbuild, picked for each joint. We explain the product when we quote.
Can I do it myself?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Do you take out the old sealant first?
Yes, every time. New sealant won’t bond properly to old, so any old material comes out before anything new goes in.
Why is there a gap in my brick wall?
A vertical gap in a long brick wall is usually a movement joint. It gives the wall room to move and needs a flexible seal, not mortar.