Greater London · England
Bexley Riverside External Mastic
Specialist external mastic for Bexley Riverside: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Moss and dirt in joints with no sealant left
- Hard, crazed mastic that has stopped moving
- Water getting into walls through failed joints
Bexley Riverside buildings and the weather
Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. With historic houses such as Hall Place and Gardens (about 1.6 miles south) nearby, there’s older building stock in the area around Bexley Riverside 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.
If you live in an older home near St Paul's, old and new materials meet at the roofline and walls, which is where sealant earns its keep. Managing a site like Normandy Primary School? Then its movement joints, gutters and trims need looking after like any other building’s. Bexley Riverside is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Bexley Riverside is about 3 miles north-west of Dartford, in Greater London. If you need external mastic in Bexley Riverside, please ring 0345 464 0079 or send us an email for a quick quote. We are based in Crawley and cover Greater London, Bexley Riverside included. Our Greater London coverage runs to 764 places, and Bexley Riverside is one of them. For nearby work, see our London page.
Jobs for external mastic in DA8, DA7 and DA1 works the same way as everywhere else we cover. We cover properties on Mill Road, Hurst Road and Bexley Road and the roads around them. We also cover the places around Bexley Riverside: Northumberland Heath (1 mile north-west), Barnehurst (1 mile south), Erith (1 mile north), North End (1 mile east) and Slade Green (1 mile east). Further out, we also cover London (12 miles west), City of Westminster (14 miles west), Marylebone (14 miles west), St Pancras (13 miles west), Shoreditch (11 miles west) and Walthamstow (12 miles north-west).
What’s near Bexley Riverside
In Bexley Riverside, that means homes and buildings near Braeburn Park, The Royal Oak pub and Trinity School and the streets around them. The closest station to Bexley Riverside is Barnehurst station, about 0.6 miles south-west. Well-known places in the area include Broadway Shopping Centre (1.4 miles south-west) and Erith and District Hospital (0.5 miles north). Not far away are Wansunt Pit.
External mastic in Bexley Riverside
Getting the depth right is half the job. Closed-cell backing rod sets the depth and stops the sealant sticking to the back, leaving it bonded to two faces so it can move with the wall. We work on brickwork movement joints, joints between brick and frames and façade panels, and common reasons people get in touch are weathered mastic that no longer stretches and moss and dirt in joints with no sealant left.
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, and both kinds of building are found across London.
All our work comes with our 12-month guarantee.
- Location
- Bexley Riverside (DA8, DA7, DA1)
- Wider area
- Greater London
- Cover
- One year on every job
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
What the job involves on each surface
Concrete and blockwork
The face of concrete or block is often dusty, so cleaning and priming matter. We prime where the sealant needs it.
Brickwork movement joints
Vertical joints in long brick walls let the brickwork expand without cracking. We reseal them with a low-modulus sealant over backing rod coloured to suit the wall.
Leave it or put it right?
The longer a joint stays open, the more water the wall takes in. Wet masonry is more easily damaged by frost around the joint, so the damage spreads beyond the joint. Damp from a failed joint spreads quietly in older London brickwork and timber, and by the time it shows on a wall or ceiling in Bexley Riverside, the repair is bigger than the sealant job would have been.
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’ll explain the quote if you ask.
What you get with us
- Fully insured
- A choice of colours where the product allows
- We leave the area clean and tidy
- A sealant colour to suit the surroundings
Read what affects the cost or what customers say.
Work for landlords, hotels and businesses
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements and we’ll give you a quote.
Water getting past a failed joint can damage the building, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance.
DIY sealant or a professional job?
If you’ve already had a go yourself, that is fine. We cut it out and start again, so tell us about it when you ask for a quote.
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
What affects the quote in Bexley Riverside
Every job gets its own quote. These are the things that affect it:
- Whether old sealant or filler has to be cut out
- How many areas need sealing
- Which sealant suits the joint
- Whether there’s mould to deal with
Combining jobs into one visit generally makes better use of the time than several visits. You will get one clear quote for the whole job.
What we need to know
You do not need to know the technical terms. It helps if you can tell us:
- The type of property
- Photos by email, if that is easy
- Any previous sealing or DIY work
- What’s wrong with the joints now
Need a quote? Please call 0345 464 0079 or email us and tell us about the job. We’ll explain what we’d do and send you a clear quote before we start.
Bexley Riverside: your questions answered
Is parking a problem for a job in Bexley Riverside?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. That way the visit can be planned around it.
Do you work for landlords with property near Barnehurst station?
Yes. We work for letting agents and landlords as well as homeowners, and several properties can be quoted together. Just call 0345 464 0079 or drop us an email with the address and what needs doing, and we will give you a clear quote.
Do you cover Bexley Riverside?
Yes. From our base in Crawley, we cover South East England, London and all of Scotland, and that includes Bexley Riverside.
How long does the job take?
As a guide, most jobs take a few hours for a handful of joints, longer for a whole elevation. Bigger jobs take longer, and we’ll say how long yours will take.
Can you reach joints on upper floors?
It depends on the height and the site. Low-level joints are straightforward; for higher ones, send details and we will confirm the access.
Why is there a gap in my brick wall?
A movement joint is a planned break in the wall that absorbs expansion and shrinkage. It should be filled with flexible sealant, never mortar.
When is the sealant fully cured?
Most sealants are touch-dry well before they’re fully cured. We’ll tell you how long to leave the joint before we leave.
Do the sealants smell?
Some sealants have a smell while they cure, which fades as it sets. Ventilation helps.
When it is not the sealant
We won’t take on work that won’t last, so here’s what sealant can’t put right:
- Damp that is not coming from the joint
- Cracks in the bricks or render themselves, away from the joints
- Structural movement, which needs a surveyor or engineer
If in doubt, call 0345 464 0079 or email us and we’ll say what we think.
What we seal
- Brickwork movement joints
- Concrete & block
- Façade panels
- Copings & trims
- Joints between brick and frames
- Render & cladding joints
How the visit works
There is not much for you to do on the day. Show us the job and we’ll take it from there. The work itself takes a few hours for a handful of joints, longer for a whole elevation from start to finish. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Bexley Riverside. It helps if you can point us to a visitor permit or a bay close to the door.
- We start by walking round the building and agreeing the joints and the access.
- Every bit of old sealant and any mortar or debris is cut out.
- 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
- Tell us about access, such as stairs, a lift or high-level joints
- Keep children and pets away from the work area
- Tell us about any previous sealing or DIY attempts
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.