Greater London · England
External & façade joints in Slade Green, Greater London
Sealing brickwork movement joints, render, cladding and façade joints for Slade Green, backed by a 12-month guarantee. Call for a quick quote.
- Damp patches traced to an open external joint
- Movement joints filled with mortar instead of sealant
- Leaking joints around cladding and façade panels
How we handle external mastic in Slade Green
Joints in render and cladding are easy to overlook until a damp patch appears. We inspect them, agree which need doing and reseal with a weatherproof, flexible sealant in a colour to suit. Common call-outs are for rain getting behind render or cladding at a joint and weeds or debris growing in open joints, across concrete & block, copings & trims and render & cladding joints.
Newer London blocks are built with movement joints in brick and render, and with cladding joints sealed with mastic. Older terraces have their own weak points: gutter joints, roofline trims and the joint where an extension meets the original wall.
Each job carries a 12-month guarantee, whatever its size.
- Place
- Slade Green (DA8, DA1, DA7)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before work begins
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Should I try it myself first?
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. Everything old must be removed first.
If you are set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it doesn’t work out, we can still put it right.
Nearby places to Slade Green
Other services in Slade Green
What we do, step by step
Most of a good job is in the preparation, and we don’t rush it. Joints are cleaned back and dried before anything new goes in. In total, it generally 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.
- We inspect the joints and agree which need resealing and how they’ll be reached.
- The old mastic and anything lodged in the joint is removed.
- We clean both faces of the joint and prime them where the product calls for it.
- Backing rod goes in next, setting the depth and keeping the sealant off the back of the joint.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
Getting ready for the visit
- Mention if the joints have been sealed before
- Let us know about stairs, lifts or work at height
- Keep children and pets away from the work area
Ask for 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, and add pictures by email if you can.
Advice
Keeping the joints in good condition
A little care helps the new joints last. Our advice:
- Get split or bare joints resealed while the damage is small
- Never let anyone fill a movement joint with mortar
- Ask before painting over external sealant
- Tell anyone working on the walls about the movement joints
Do not let soil, plants or ivy build up against the new joints. Damp material against the sealant shortens its life.
A joint that has stopped moving pushes the movement elsewhere, normally as cracking in the brickwork or render nearby. Catch it early and you reduce the risk.
Landlord and commercial work in Slade Green
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
Landlords and letting agents in Slade Green can book us as well as homeowners. Resealing between tenancies is a simple way to keep a property in good order before the next move-in.
Why it’s worth doing now in Slade Green
The longer a joint stays open, the more water the wall takes in. In cold weather, frost can damage wet brick and render around the joint, so the damage spreads beyond the joint. 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.
Leaving a failed joint normally makes the job bigger, not smaller, because water and mould keep working on it. If you’re not sure whether it needs doing, call 0345 464 0079 or email us and we will give you an honest view and a quote.
Why us?
- We never seal over old sealant
- ARBOMaster approved applicator
- Anti-fungal sanitary silicone in wet areas
- We agree the colour with you first
Take a look at how sealant jobs are priced or what customers say.
Questions from Slade Green
Is parking a problem for a job in Slade Green?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly.
Do you cover Slade Green for external mastic?
Yes. Our work covers London and the South East, and Slade Green is part of that. Just ring 0345 464 0079 or send us an email with a few details of the job, and we’ll give you a clear quote.
Can new sealant go over the old?
No, it won’t last. It can look neat for a few weeks, but the new bead soon lifts. The old sealant has to come out completely.
What is backing rod for?
The foam is closed-cell backing rod. It stops the sealant going in too deep and bonding to three sides so it can flex with the joint.
What sealant do you use?
Each joint gets the product that suits it. Where it moves, gets wet or faces the weather makes a difference.
Where is Mr Mastic based?
Mr Mastic is based in Crawley. Our applicators cover Slade Green, along with the rest of our area.
Can you do several jobs on one visit?
Of course. Doing several areas at once is normally more efficient, so mention them when you ask for a quote.
Can you seal joints between render and window frames?
Yes. Materials like render, brick, metal and uPVC all move differently, so a flexible sealant is needed where they meet. We choose one that suits both surfaces.
Honest limits
We’d rather tell you now than do work that will not last, so these are the limits:
- Cracks in the bricks or render themselves, away from the joints
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
- Subsidence or other structural problems
If in doubt, ring 0345 464 0079 or email us and we will say what we think.
Joints and surfaces we work on
- Brickwork movement joints
- Render & cladding joints
- Copings & trims
- Façade panels
- Joints between brick and frames
- Concrete & block
What we are called out for in Slade Green
Some movement joints have been pointed up with mortar, often by someone who didn’t know what it was for. The joint can’t move, so the wall cracks somewhere else instead.
The most common problems we see are:
- Movement joints filled with mortar instead of sealant
- Brick movement joints where the sealant has split
- Damp patches traced to an open external joint
- Leaking joints around cladding and façade panels
As a London address, Slade Green can be tricky for parking: let us know about parking bays, permits or a driveway.
What your quote should include
- What the quote includes, VAT included or not
- What happens if they find a problem under the old sealant
- Is the old sealant removed completely?
- What guarantee comes with the work
External mastic in Slade Green: local notes
With historic houses such as Hall Place and Gardens (about 2.1 miles south-west) nearby, there’s older building stock in the area around Slade Green as well as newer homes. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth. The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
For landlords with property near Slade Green station, outside joints that have cracked can let damp into a rental, so check them between lets. If you live in an older home near St. Augustine's Church, older walls, gutters and the joints where extensions meet them need a flexible sealant.
Slade Green is about 1 mile south-east of Erith, in Greater London. For external mastic in and around Slade Green, please ring 0345 464 0079 or drop us an email for a quick quote. We cover Greater London from our Crawley base. We cover 764 towns and villages across Greater London, from the larger towns to small villages. London is on our list too, about 13 miles from Slade Green.
Jobs for external mastic in DA8, DA1 and DA7 is quoted and booked the same way as anywhere else. Streets in the area include Oak Road, Elm Road and Moat Lane. We also cover North End (1 mile west), Barnes Cray (1 mile south), Bexley Riverside (1 mile west), Barnehurst (1 mile west) and Northumberland Heath (1 mile west). Further out, we also cover London (13 miles west), City of Westminster (15 miles west), Marylebone (15 miles west), St Pancras (14 miles west), Shoreditch (12 miles west) and Walthamstow (13 miles north-west).
Local landmarks in Slade Green
Around Slade Green, our work takes us to homes and buildings near Braeburn Park, Railway Tavern and Haberdashers' Aske's Crayford Academy. Slade Green has its own railway station: Slade Green station. Well-known places in the area include Broadway Shopping Centre (2.3 miles west) and Erith Museum (1.3 miles north-west). The countryside around Slade Green includes Wansunt Pit.