Greater London · England
Custom House External Mastic
Sealing brickwork movement joints, render, cladding and façade joints in Custom House, with a one-year guarantee on every job. Ask us for a quote.
- Joints where the bead has come unstuck
- Joints pointed up with cement by mistake
- Brick movement joints where the sealant has split
What external mastic looks like in Custom House
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. London terraces and converted houses often share gutters, downpipes and walls, so check who is responsible for the outside before booking.
Homes close to St Matthew's Church include some older properties, and the joints between older walls, newer extensions and the roofline need a sealant that can move. If you look after a building such as St Joachim's Catholic Primary School, its movement joints, gutters and trims need looking after like any other building’s. Rented homes near Custom House station change hands often, and failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Custom House is about 1 mile south of Canning Town, in Greater London. Across the E16 area, we cover external mastic for homes and businesses. Custom House is one of 764 places in Greater London we cover.
All of E16 and E13 is within our area for external mastic, from the main roads to the quietest streets. Whether your property is on Tree Road, Ethel Road and Booth Road or a nearby road, we can help. Custom House is on the A1020, so it’s easy for us to get to. Other places close to Custom House include West Silvertown (1 mile south-west), Silvertown (1 mile south), Canning Town (1 mile north), Royal Docks (1 mile east) and Limmo Peninsula (1 mile west). Larger places within reach include London (5 miles west), City of Westminster (8 miles west), Marylebone (8 miles west), Kensington (10 miles west), St Pancras (6 miles west) and Shoreditch (5 miles west).
Local landmarks in Custom House
Locally, jobs take us to homes and businesses close to Thames Barrier Park, The Royal Docks Community School and Royal Docks Academy. There’s a railway station in Custom House itself: Custom House station. Other landmarks nearby include Gallions Reach Shopping Park (2.2 miles east) and Charlton Athletic Museum (1.5 miles south). For a walk, there’s Gilbert's Pit and Tower Hill.
External mastic for homes and businesses in Custom House
Getting the depth right is half the job. Backing rod controls how deep the sealant goes and keeps it off the back of the joint, leaving it bonded to two faces so it can move with the wall. Typical jobs include old sealant gone brittle and cracked and brick movement joints where the sealant has split, on concrete & block, copings & trims and joints between brick and frames.
Working on the outside of a London home means planning access: shared paths, upper floors and parking. For a home in Custom House, tell us how high the joints are and how to reach the back of the building.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we will put it right.
- Location
- Custom House (E16, E13)
- Wider area
- Greater London
- Cover
- A year, on every job
- Price
- A clear price before we start
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Also near Custom House
Other services in Custom House
Custom House: your questions answered
Can you help a landlord with a rental near Custom House station?
Yes. We work for landlords and agents as well as homeowners. You can call 0345 464 0079 or send us an email with the details for a clear quote.
Can you do external mastic in Custom House?
Yes. Our work covers London and the South East, and Custom House is part of that. You can ring 0345 464 0079 or email us and let us know what needs doing.
Can you seal joints between two different materials?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. We pick a colour that works with both materials.
What do you need from me for a quote?
The location, the problem and the rough size of the job. Photos by email help too.
Can you match the colour of my brickwork?
The aim is a neat, even joint in a colour that suits the wall. Colour is agreed with you before we begin from the range available.
Will the old sealant be removed?
Yes. Sealing over the old bead is the commonest cause of early failure, and it’s something we never do.
What is backing rod for?
The foam is closed-cell backing rod. It keeps the sealant at the right depth and bonded to the sides only so it can flex with the joint.
Can you quote for more than one area?
Yes. Tell us about everything you’d like done and you’ll get one quote.
Keeping the joints in good condition
Aftercare is simple, and it makes a real difference:
- Wash walls gently around the sealant
- Have failed joints looked at early
- Walk round the building once a year and look at the joints
- Deal with leaking gutters that soak the joints below
Do not let soil, plants or ivy build up against the new joints. Anything that holds water against the joint wears it out sooner.
If you can see gaps, plants or bare sections in a joint, have it checked. Early work is quicker and leaves a better finish.
The process
Once we’re on site, we compare the joints with what we discussed. If we find something unexpected, we talk it through with you first. Most jobs then take a few hours to a few days, depending on the length of joint and the access. For a job in Custom House, parking and access are the things to plan: let us know about parking, the floor we will be working on and any lift or shared entrance.
- 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.
- We push in closed-cell backing rod so the sealant is the right depth and bonds to the sides only.
- We gun in a flexible exterior sealant in a colour that suits the wall and tool it neatly.
Getting ready for the visit
- Mention any sign-in or site rules at work premises
- Let us know about stairs, lifts or work at height
- Let us know about parking restrictions
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 email pictures if that is easy.
Related advice
Why deal with it now?
Done well, a resealed joint is a neat, straight line that suits the wall. A hurried job with smeared edges and no backing looks worse and fails sooner. In London conversions, one flat’s bathroom is often above another flat’s ceiling, so a small leak from tired sealant can mean a neighbour’s ceiling and a lot of disruption. Dealing with it early is far simpler for homes in Custom House.
Homes and businesses are quoted the same way: the amount of work, how we reach it and what it needs, along with when we can work on site. Ask us for a quote and we’ll go through it with you.
Why choose Mr Mastic in Custom House
- We never seal over old sealant
- Fully insured
- A sealant colour to suit the surroundings
- Rated 4.9 stars on Google
Take a look at how sealant jobs are priced or customer reviews.
Surface by surface
Brickwork movement joints
Vertical joints in long brick walls let the brickwork expand without cracking. They’re resealed over backing rod with a low-modulus sealant in a colour to suit the brick.
Copings and trims
Coping and trim joints face rain and sun head on. Each is resealed with a weatherproof, flexible sealant.
What affects the quote in Custom House
We do not publish a price list, because no two jobs are the same. What we look at:
- The number of rooms or windows
- Mould in or behind the old joints
- When we can work, for business premises
- The size of the job
The cost reflects the work involved, not guesswork. That’s why we ask a few questions first and agree the price before starting.
Asking for a quote
There’s no need for technical detail. Just tell us:
- The rough size of the job
- A few pictures by email, if you can
- The type of property
- Access, such as stairs, a lift or height
We don’t publish a price list. Instead, we send you a clear quote for your job. To get started, phone 0345 464 0079 or email us.
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.
If you’re 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.
When something else is needed
In fairness, some problems need a different trade:
- Structural movement, which needs a surveyor or engineer
- Walls that need new movement joints cut into them
- Render that is blown, hollow or coming away
Not sure which it is? You can phone 0345 464 0079 or email us and we will tell you honestly before you book.
What we seal
- Concrete & block
- Façade panels
- Render & cladding joints
- Joints between brick and frames
- Copings & trims
- Brickwork movement joints