Greater London · England
External Mastic in Chiswick
Sealing brickwork movement joints, render, cladding and façade joints for Chiswick, backed by a 12-month guarantee. Ask us for a quote.
- Plants rooting in failed movement joints
- Damp patches traced to an open external joint
- Joints pointed up with cement by mistake
How we handle external mastic in Chiswick
External mastic is a job where short cuts show quickly. New sealant over old, joints packed with mortar and beads with no backing rarely last long. We strip the joint back and start again. If you have hard, crazed mastic that has stopped moving and joints pointed up with cement by mistake, we can help, whatever the surface.
Modern London flats rely on sealed movement joints and cladding joints. 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.
You are covered for a year from the day we finish. If there’s a problem with it, please call 0345 464 0079 or drop us an email.
- Where
- Chiswick (W4, SW14)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Quote
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
How the job changes by surface
Joints between dissimilar materials
Each side of the joint may need its own preparation. Both surfaces are cleaned and primed as the product requires.
Copings and trims
Coping and trim joints face rain and sun head on. Each is resealed with a weatherproof, flexible sealant.
Walls and rooflines in Chiswick
Rainfall in the South East is lower than in much of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. With historic houses such as Hogarth's House (about 0.2 miles south-west) nearby, there’s older building stock in the area around Chiswick 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.
For site and facilities teams at buildings such as The William Hogarth Primary School, movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. Chiswick is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Chiswick is about 1 mile south of Acton, in Greater London. Whether you’re in the middle of Chiswick or further out, external mastic is available for homes and businesses alike. Our area takes in 764 places across Greater London, large and small. Our London page covers work nearby, about 7 miles away.
Here we cover the W4 and SW14 postcode area for external mastic. Whether your property is on Pumping Station Road, Dale Street and Devonshire Road or anywhere close by, our applicators can take on the job. If you’re just outside Chiswick, we cover Turnham Green (1 mile south), Old Chiswick (1 mile south-east), Grove Park (1 mile south-west), Gunnersbury (1 mile west) and Strand-on-the-Green (1 mile west). Further out, we also cover London (7 miles east), City of Westminster (5 miles east), Marylebone (5 miles east), St Pancras (6 miles north-east), Shoreditch (8 miles east) and Walthamstow (12 miles north-east).
Landmarks near Chiswick
We work in homes and buildings around Polish Library POSK in London, Mawson Arms and Chiswick School and the streets around them. Also close by are Turnham Green (0.5 miles west) and The Swedish School (0.6 miles south-east). The closest station to Chiswick is Chiswick station, about 0.8 miles south-west. Other landmarks nearby include West London Hospital (1.5 miles east) and Kurdish Museum Library and Archive (0.8 miles east). Open spaces near Chiswick include Campden Hill and Duke's Hollow.
When to call us in Chiswick
The wrong product in a moving joint is a classic cause. A stiff, general-purpose sealant cannot cope with a joint that moves a lot, so it pulls away from the edges.
Look out for these signs:
- Damp patches traced to an open external joint
- Joints pointed up with cement by mistake
- Failed sealant between panels on a façade
- Joints where the bead has come unstuck
Letting a property close to Chiswick station? Then outside joints that have cracked can let damp into a rental, so check them between lets.
Questions to ask before booking
- How hidden problems are handled
- Whether you can choose the colour
- Who turns up on the day
- How long to leave it before use
How we quote for external mastic
The price is agreed before any work begins. It’s based on:
- Whether the work is at height
- The product the joint needs
- The number of rooms or windows
- How much there is to do
The cost reflects the work involved, not guesswork. That’s why we ask about the job first and give you a clear quote before work begins.
Asking for a quote
To help us quote quickly, let us know:
- A few photos by email, if you can
- What the problem is, such as mould, gaps, leaks or cracking
- Where the job is, and your postcode
- How we’d reach the joints
We do not publish a price list, because every job is different. Instead, your job gets its own clear quote. To arrange one, phone 0345 464 0079 or send us an email.
More services for Chiswick
Aftercare tips
A little care helps the new joints last. We recommend:
- Keep soil, plants and ivy away from the joints
- Avoid pressure-washing directly into sealant joints
- Leave the joints unpainted unless we have said otherwise
- Have failed joints looked at early
Look over the joints once a year, ideally after winter. Watch for splits, edges coming away or growth in the joint.
Once a joint cannot move, the wall finds another way, generally as cracking in the brickwork or render nearby. Catch it early and you reduce the risk.
How the visit works
At the end, we look at the finished work together and explain the cure time. The work normally takes anything from a few hours to several days, depending on the building, depending on the size of the job. In Chiswick, 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.
- Failed sealant is removed back to clean, sound faces.
- 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
- For indoor joints, keep the area dry beforehand if you can
- Plan for the work area to be out of bounds to pets and children
- Let us know about stairs, lifts or work at height
Ask for a quote
Want a quote for external mastic? Please phone 0345 464 0079 or send us an email and tell us about the job. You will know what we plan to do, and what it will cost, before any work begins.
Advice
DIY sealant or a professional job?
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 fails, we can still redo it.
What a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is chosen for how the joint moves and where it is.
Common questions in Chiswick
Is parking a problem for a job in Chiswick?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
Can you help a landlord with a rental near Chiswick station?
Yes. We work for letting agents and landlords as well as homeowners. Just call 0345 464 0079 or send us an email with the address and what needs doing, and we’ll give you a clear quote.
Do you take out the old sealant first?
Yes. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Can new sealant go over the old?
No. New silicone won’t bond to old silicone, and it traps any mould or water underneath. It all has to come out first.
What colours does the sealant come in?
Exterior sealants are made in a range of colours, from greys and browns to whites and stone shades. We pick the one that suits your wall best so it does not stand out.
Can you reach joints on upper floors?
It depends on the height and the site. Ground-floor joints are simple; for higher ones, send details and we’ll confirm the access.
Is there a guarantee?
Yes. Every job comes with our 12-month guarantee.
What information do you need?
Let us know what needs doing and where. We’ll ask anything else we need to know.
Why it’s worth doing now in Chiswick
The longer a joint stays open, the more water the wall takes in. In cold weather, frost can damage wet brick and render, so the problem grows beyond the joint itself. In London conversions, one flat’s bathroom is often above another flat’s ceiling, and a slow leak from a failed seal can end up in the flat below. Dealing with it early is far simpler for homes in Chiswick.
The cost depends on how much there is to do, how much old material has to come out and access to the work. You’ll have a clear quote before any work starts, so you know where you stand.
What you get with us
- Rated 4.9 stars on Google
- We leave the area clean and tidy
- We’re fully insured
- Experience in homes, commercial sites and hotels
Take a look at how sealant jobs are priced or our reviews.