Kent · England
Northdown External Mastic
Movement joints in Northdown need attention? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Hard, crazed mastic that has stopped moving
- Movement joints with cracked, split or missing sealant
- Moss and dirt in joints with no sealant left
How to look after the new joints
Looking after new joints is easy, and it makes a real difference:
- Check external joints each spring
- Leave the joints unpainted unless we have said otherwise
- Fix overflowing gutters above sealed joints
- Have failed joints looked at early
Don’t let soil, plants or ivy build up against the new joints. Anything that holds water against the joint wears it out sooner.
Leaks behind façade panels and render often go unseen. By the time there’s a damp patch, the damage can be well established so early resealing is worth it.
External mastic in Northdown, done properly
For buildings in Northdown, we reseal external joints of all kinds, from brick movement joints to cladding panels. The preparation is the same whatever the wall: clean joint faces and the right depth. We work on copings & trims, brickwork movement joints and render & cladding joints, and the jobs we see most are leaking joints around cladding and façade panels and movement joints filled with mortar instead of sealant.
Homes around Northdown range from older cottages to newer houses, with walls and rooflines of every type. Older homes need their gutter and trim joints kept tight, newer ones their movement joints.
Whatever the size of the job, it’s backed by our 12-month guarantee.
- Place
- Northdown (CT9, CT10)
- Wider area
- Kent
- Cover
- A year, on every job
- Quotes
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Your questions about external mastic in Northdown
Do you work for landlords with property near Broadstairs station?
Yes, rental work is part of what we do. Just call 0345 464 0079 or email us and tell us about the property, and we’ll send you a clear quote.
Will you come out to Northdown?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
Do the sealants smell?
That depends on the sealant. Some smell for a while, some hardly at all.
Can you reach joints on upper floors?
That depends on how high the joints are and the ground below. Low-level joints are straightforward; for higher ones, send details and we will confirm the access.
What information do you need?
Only a few details: where it is, what you’ve noticed and how we reach it. Then call 0345 464 0079 or drop us an email.
What does external mastic cost?
There’s no set price, as it depends on the job: its size, the old material, access and the product needed. We agree the price before any work begins.
When will the joints need doing again?
It varies from wall to wall: joints on exposed walls or with a lot of movement age sooner. A yearly look will tell you when they need doing. Our work comes with a 12-month guarantee.
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.
DIY versus a professional finish
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and does not move well, and getting the depth right matters as much as the look.
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Leave it or put it right?
Sealing over the top of old mastic does not hold for long. The new layer cannot bond properly to old, weathered material, so we always take the old sealant out. In an older home around Northdown, damp from a failed joint can get into timber and plaster, which is far harder to put right than the sealant itself.
The cost depends on the amount of work, how much old material has to come out and access to the work. You’ll have a clear quote before any work starts.
Why book with us
- Old sealant always removed completely
- Sealant colour chosen to suit
- Trusted Arbo and Everbuild sealants
- Over 20 years’ experience
Take a look at how sealant jobs are priced or customer reviews.
Places near Northdown
What else we do in Northdown
Honest limits
Some problems need a builder, plumber or other trade rather than us:
- Adding movement joints to masonry that has none
- Loose or hollow render, which needs re-rendering
- Subsidence or other structural problems
If you are not sure, just phone 0345 464 0079 or send us an email and we will give you a straight answer.
Surfaces we seal
- Render & cladding joints
- Brickwork movement joints
- Joints between brick and frames
- Façade panels
- Copings & trims
- Concrete & block
Walls and rooflines in Northdown
Northdown is close to the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. Both are hard on movement joints and outside wall joints, which can dry out and crack sooner where a building faces the weather. London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
For an older house near a landmark such as St Philip, old and new materials meet at the roofline and walls, which is where sealant earns its keep. Rented homes near Broadstairs station change hands often, and failed wall and movement joints let damp in, so they’re worth checking between tenancies. For site and facilities teams at buildings such as Palm Bay Primary School, larger buildings have long runs of movement joint that eventually need resealing.
Northdown is about 2 miles east of Margate, in Kent. Homes, rented property, offices and hotels in Northdown can book us for external mastic. The work is guaranteed for a year. Across Kent, we cover 922 places, and Northdown is one of them. We also work in Chelmsford, around 47 miles away.
We work across the CT9 and CT10 postcode area for external mastic. Streets in the area include Old Road, Holly Lane and Green Lane. If you are just outside Northdown, we cover Palm Bay (1 mile north-west), Cliftonville (1 mile west), Kingsgate (1 mile east), St Peter's (1 mile south) and Broadstairs (2 miles south). Larger places within reach include Ramsgate (3 miles south), Deal (12 miles south), Herne Bay (12 miles west), Walmer (13 miles south), St Lawrence (3 miles south) and Newington (3 miles south-west).
Around Northdown
Locally, jobs take us to homes and businesses close to Captain Digby Inn and Dane Court Grammar School and the streets around them. For rail, the closest station is Broadstairs station, about 1.8 miles south of the centre. Other landmarks nearby include Westwood Cross (2.1 miles south-west) and Queen Elizabeth the Queen Mother Hospital (1.4 miles south-west).
What we do, step by step
Every visit runs the same way: we look at the joints together, protect the area around them, carry out the job and clear up. Most jobs take a few hours to a few days, depending on the length of joint and the access. For a job in Northdown, we agree the time, the access and parking before the day. Outdoor jobs depend on a dry day, since sealant needs a dry surface.
- We start by walking round the building and agreeing the joints and the access.
- We cut out the old mastic and rake out anything in the joint.
- The faces are brushed clean and primed where the product requires it.
- We fit closed-cell backing rod to control the depth.
- We apply the sealant, tool it and check the whole run.
Preparing for the visit
- Where the joints are inside, avoid wetting them before we arrive
- Clear items away from the joints we are working on
- Plan for the work area to be out of bounds to pets and children
How to get a quote
Need a quote? Please phone 0345 464 0079 or drop us an email with a few details. We will explain what we’d do and send you a clear quote before any work starts.
Advice
Different surfaces, different methods
Render joints
Cracks along render joints let water in behind the coat. A sound joint keeps the render dry behind and protects the render itself.
Concrete and blockwork
Blockwork and concrete shrink over time and move with the seasons. Their movement joints are sealed over backing rod with a flexible sealant.
Landlords, agents and businesses in Northdown
Mouldy or split sealant often shows up at the end of a tenancy. Several properties can be quoted together.
For anyone letting property in or around Northdown, jobs at different addresses can be quoted together. Just tell us the addresses and what each one needs, and photos by email help.