Greater London · England
External Mastic in Brimsdown
External mastic for Brimsdown and the surrounding area: the right sealant, proper preparation and a neat finish. Ask us for a quick quote.
- Moss and dirt in joints with no sealant left
- Brick movement joints where the sealant has split
- Hard, crazed mastic that has stopped moving
About our external mastic in Brimsdown
Where two different materials meet, such as brick and render or blockwork and metal, they move at different rates. A flexible exterior sealant takes up that movement. Common call-outs are for panel joints letting water in and water getting into walls through failed joints, on concrete & block, copings & trims and brickwork movement joints.
In London terraces and converted houses, gutters and walls are often shared with the house next door, so one failed joint can cause damp for more than one household. In a converted house in Brimsdown, it’s worth checking who is responsible for the outside before booking.
Whatever the size of the job, you get the same 12-month guarantee in Brimsdown and across Greater London.
- Where
- Brimsdown (EN3)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
DIY sealant or a professional job?
Sealing over old silicone is the commonest DIY error. Silicone does not stick to old silicone, so it peels away and traps moisture behind it. Everything old must be removed first.
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
FAQs for Brimsdown
Do you cover Brimsdown for external mastic?
Yes. We work across London and the South East, and Brimsdown is part of that. Just call 0345 464 0079 or email us with a few details of the job.
Do you work for landlords with property near Brimsdown station?
Yes, rental work is part of what we do. You can call 0345 464 0079 or email us with the address and a few details, and we’ll give you a fixed price before work begins.
Can you seal over the old sealant?
No, and we never do. It can look neat for a few weeks, but the new layer lifts away from the old one. The old sealant has to come out completely.
What sealant do you use?
Products from Arbo and Everbuild, among others, chosen to suit the joint. We’ll tell you what we’re using and why.
Will the new joint stand out?
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 the joint doesn’t draw the eye.
Do you hold any approvals?
Yes. Mr Mastic is an ARBOMaster approved applicator and we are fully insured too.
What should I tell you?
Let us know what needs doing and where, with pictures by email if possible. If we need more, we will ask.
Should I point up the gap in my brickwork?
No. Cement or mortar cannot stretch. If it has already been filled, we can usually cut it out and reseal it.
Leave it or put it right?
It often makes sense to reseal all the failing joints on an elevation together. Joints of the same age tend to fail together, and access only has to be arranged once. Converted houses in London often have a bathroom above someone else’s living room, so a small leak from tired sealant can mean a neighbour’s ceiling and a lot of disruption. Putting it right early is much less trouble.
A few things move the cost up or down: how much old sealant there is and how stubborn it is, any mould to treat, and whether the work is at height. We take all of that into account in your quote.
What you get with us
- Fully insured
- A choice of colours where the product allows
- We agree the colour with you first
- Anti-fungal silicone where joints get wet
Looking after it afterwards
How long the joints last depends on use and care. We suggest:
- Leave the joints unpainted unless we’ve said otherwise
- Wash walls gently around the sealant
- Act on the first splits you see
- Show decorators and builders where the movement joints are
Do not paint over the new sealant unless we have said the product is paintable. Paint can crack on a flexible joint and spoil the finish.
Water getting behind cladding or render can go unnoticed for a long time. By the time there’s a damp patch, the damage can be well established, so it’s worth resealing at the first signs.
What affects the cost of external mastic
Every job gets its own quote. This is what makes a difference:
- Which sealant suits the joint
- The number and length of the joints
- Whether the work is at height
- The old material and how stubborn it is
Leaving a failed joint normally makes the job bigger, not smaller, as water and mould keep getting in. If you’re not sure whether it needs doing, call 0345 464 0079 or drop us an email for an honest opinion and a quote.
What we need to know
Before you ask for a quote, have a think about:
- Any access issues, like height or stairs
- Roughly how big the job is
- The type of property
- Where the job is, and your postcode
Need a quote? Please ring 0345 464 0079 or email us and tell us about the job. You will know what we plan to do, and what it will cost, before any work begins.
Signs you need external mastic in Brimsdown
Some movement joints have been pointed up with mortar by mistake. The joint can’t move, so the wall cracks somewhere else instead.
Most people get in touch after spotting something like this:
- Panel joints letting water in
- Hard, crazed mastic that has stopped moving
- Failed seals between different materials
- Rigid filler in a joint that should flex
If you live in an older home near Ss Peter and Paul Church, the joints between older walls, newer extensions and the roofline need a sealant that can move.
Comparing quotes
- What the cure time is
- Who does the work, and how experienced they are
- Is the old sealant removed completely?
- Is VAT in the price?
What we do, step by step
We bring everything the job needs with us. Once we’ve agreed what’s being done, we protect the area and start. It normally takes anything from a few hours to several days, depending on the building. In Brimsdown, 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.
- We prime the faces where required.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Before we arrive
- Let us know about earlier repairs to the joints
- On commercial sites, let us know about site rules
- Clear the area around the work
Ask for a quote
Asking for a quote is easy: let us know the job and the location. Photos by email help us understand the job.
Read more
Nearby places to Brimsdown
What else we do in Brimsdown
Brimsdown buildings and the weather
London terraces and converted houses often share gutters, downpipes and walls, so it’s worth agreeing who is responsible before work starts. 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.
For landlords with property near Brimsdown station, failed wall and movement joints let damp in, so they’re worth checking between tenancies. If you look after a building such as Brimsdown Primary School, its movement joints, gutters and trims need looking after like any other building’s.
Brimsdown is about 2 miles south-west of Waltham Abbey, in Greater London. Across the EN3 area, we cover external mastic for homes and businesses. Across Greater London, we cover 764 places, and Brimsdown is one of them. We also work in London, about 11 miles from Brimsdown.
Jobs for external mastic in EN3 works the same way as everywhere else we cover. If you need external mastic at a property on Jute Lane, Croft Road and Bowood Road or anywhere close by, we can help. We also cover Enfield Lock (1 mile north), Enfield Highway (1 mile west), Enfield Island Village (1 mile north-east), Enfield Wash (1 mile north-west) and Sewardstone (1 mile east). We also work in nearby towns such as London (11 miles south), City of Westminster (11 miles south-west), Marylebone (11 miles south-west), Kensington (13 miles south-west), St Pancras (10 miles south-west) and Shoreditch (10 miles south).
Near you in Brimsdown
We work in homes and buildings around Aylands School, Lee Valley Park and Aylward Academy. Brimsdown has its own railway station: Brimsdown station. Other landmarks nearby include St Michaels Hospital (2.5 miles west) and Edmonton Green Shopping Centre (2.8 miles south-west). Green spaces nearby include Bowyer's Water and Ainslie Wood.
When something else is needed
In fairness, some problems need a different trade:
- Cracking across the wall rather than at a joint
- Rising or penetrating damp from elsewhere in the wall
- Adding movement joints to masonry that has none
If you are not sure, just call 0345 464 0079 or drop us an email and we’ll give you a straight answer before you book.
Surfaces we seal
- Façade panels
- Brickwork movement joints
- Joints between brick and frames
- Render & cladding joints
- Concrete & block
- Copings & trims