Kent · England
External & façade joints in Southfleet, Kent
External mastic across Southfleet and nearby, with old sealant always removed completely and a one-year guarantee.
- Failed sealant between panels on a façade
- Weeds or debris growing in open joints
- Damp patches traced to an open external joint
Aftercare tips
Good habits help new joints last longer. Our tips:
- Keep movement joints as flexible joints, not mortar
- Ask before painting over external sealant
- Check external joints each spring
- Fix overflowing gutters above sealed joints
Only paint over the joint if we have confirmed the sealant can take paint. Paint can crack on a flexible joint, and paint can crack as the joint moves.
Act while the splits are small. At that stage it’s a simple cut out and reseal with no damage behind it to deal with.
How we handle external mastic in Southfleet
Movement joints let brickwork, render and cladding expand and shrink without cracking. The sealant in it has to stretch and squeeze for years, and when it fails, the wall takes the strain and water finds a way in. If you are dealing with movement joints filled with mortar instead of sealant and weathered mastic that no longer stretches, we can help, on render & cladding joints, joints between brick and frames and concrete & block alike.
In a village or hamlet like Southfleet, older cottages and farm buildings often stand in the open, where walls and rooflines take the weather head on. Gutter joints and wall joints there need a sealant that can flex and stay put.
Every job comes with a 12-month guarantee.
- Location
- Southfleet (DA13)
- Wider area
- Kent
- Guarantee
- One year on every job
- Quote
- Quoted before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Landlords, agents and businesses in Southfleet
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Keeping joints in good order is simple maintenance.
We also work for property managers and facilities teams in Southfleet and across Kent. Several sites can go on one quote, and we’re fully insured.
What sealant work cannot fix
Honest advice matters more to us than a booking, so here’s what sealant can’t fix:
- Render that’s blown, hollow or coming away
- Movement that is more than a sealant joint can take
- Adding movement joints to masonry that has none
Not sure which it is? You can call 0345 464 0079 or email us and we will tell you honestly before booking.
What we seal
- Copings & trims
- Façade panels
- Render & cladding joints
- Concrete & block
- Brickwork movement joints
- Joints between brick and frames
How we quote for external mastic
Every job gets its own quote. This is what makes a difference:
- How much there is to do
- How easy the joints are to reach
- The number of rooms or windows
- The type of sealant required
Commercial jobs are quoted on the same basis as homes: the amount of work, the access and the products needed. Ask us for a quote and we’ll go through it with you.
Helping us quote
There’s no need for technical detail. It helps if you can tell us:
- The address or postcode of the job
- If someone has resealed it before
- Any access issues, like height or stairs
- Photos by email, if that’s easy
Want a quote for external mastic? Please phone 0345 464 0079 or email us and tell us about the job. You’ll know what we plan to do, and what it will cost, before any work begins.
Also near Southfleet
Also in Southfleet
Questions from Southfleet
Can you do external mastic in Southfleet?
Yes. We work across London and the South East, and Southfleet is part of that. You can phone 0345 464 0079 or send us an email and tell us what needs doing, and we’ll give you a clear price.
Is Southfleet within the area you cover?
Yes, smaller places are covered as well as towns. We work across London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Can you reach joints on upper floors?
It depends on the building. Send us photos and a rough idea of the height.
Can you seal over the old sealant?
No, because it fails. The old sealant always comes out first, so the new joint bonds to clean surfaces.
Can tenants book the work?
We are happy to deal with the tenant, landlord or agent. Just make sure your landlord agrees.
Can you quote for more than one area?
Yes, we can. More than one area can go on one quote.
Is it OK to fill a movement joint with cement?
No, not where the gap is a movement joint. Filling it with mortar defeats its purpose, and the wall may crack nearby. A flexible sealant is the right fill.
Do I need to be at home?
We need access to the joints, so we will agree that with you when we book. Indoors, that normally means someone at home.
What we are called out for in Southfleet
Joints sealed without backing rod, or far too deep, rarely last. Sealant bonded to three sides has nowhere to go and tears as soon as the joint widens.
People generally contact us when they notice something like this:
- Gaps where render, brick and frames meet
- Hard, crazed mastic that has stopped moving
- Rain getting behind render or cladding at a joint
- Joints with sealant missing in places
For an older house near a landmark such as Church of St Nicholas, the joints between older walls, newer extensions and the roofline need a sealant that can move.
Questions to ask before you book
- What happens if the job turns out different
- Whether the sealant suits the joint
- What the quote includes, VAT included or not
- What insurance they hold
DIY versus a professional finish
A careful DIYer can reseal a simple joint, 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.
The difference is mostly in the preparation and the product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, and the work is guaranteed for a year.
What external mastic looks like in Southfleet
With historic houses such as Cobham College (about 3.6 miles south-east) nearby, there’s older building stock in the area around Southfleet as well as newer homes. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material. 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.
For site and facilities teams at buildings such as Sedley's Church of England Voluntary Aided Primary School, larger buildings have long runs of movement joint that eventually need resealing. Rented homes near Longfield station change hands often, and failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Southfleet is about 2 miles south-west of Northfleet, in Kent. Homes, rented property, offices and hotels in Southfleet is covered for external mastic, old or new, large or small. Every job comes with our one-year guarantee. We cover 922 towns and villages across Kent, from the larger towns to small villages. You can also see our page for London, roughly 19 miles from Southfleet.
We cover every part of the DA13 postcode area for external mastic and the streets around it. You will find streets such as Red Street, Gloxinia Road and Brakefield Road, all of which we cover. If you are just outside Southfleet, we cover Hook Green (1 mile south-west), Northfleet Green (1 mile east), Betsham (1 mile north-west), Painters Ash (1 mile north-east) and Springhead (1 mile north). Further out, we also cover Maidstone (13 miles south-east), Dartford (5 miles north-west), Sevenoaks (11 miles south-west), Gravesend (3 miles north-east), Tonbridge (15 miles south) and Swanley (7 miles west).
Landmarks near Southfleet
In Southfleet, that means homes and buildings near Northfleet School for Girls, Black Lion pub and Longfield Chalk Bank. For rail, the closest station is Longfield station, roughly 1.5 miles south-west. Nearby you’ll also find Gravesham Community Hospital (2.7 miles north-east) and Bluewater (2.9 miles north-west). For a walk, there’s Sawyers Lake.
What we do, step by step
Most of a good job is in the preparation, so that’s where we spend the time. Every joint is cleaned and dried before new material goes in. In total, it usually takes anything from a few hours to several days, depending on the building. In a small place like Southfleet, access is generally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We look at every joint and agree a colour to suit the wall.
- We take out the old sealant until the faces are sound.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- We prime the faces where required.
- We gun in low-modulus sealant and tool it neatly.
Preparing for the visit
- Let us know about stairs, lifts or work at height
- For business premises, tell us about site rules or sign-in
- Mention any leaks or damp you’ve noticed
Getting a quote
Getting a quote is simple: let us know what needs doing and where, and roughly how big it is. A few pictures by email make the job easier to understand.