Kent · England
External Mastic in Northfleet
We cover Northfleet for sealing brickwork movement joints, render, cladding and façade joints. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Rain getting behind render or cladding at a joint
- Panel joints letting water in
- Rigid filler in a joint that should flex
Keeping the joints in good condition
A little care helps the new joints last. We recommend:
- Keep high-pressure jets off the joints
- Keep water from gutters off the wall
- Ask before painting over external sealant
- Keep soil, plants and ivy away from the joints
Follow the cure time we give you before the joint is knocked or disturbed. The surface skins over quickly, but full cure takes longer.
Act while the splits are small. At that stage it’s a simple cut out and reseal.
External mastic in Northfleet, done properly
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 where mortar or filler would crack. We work on render & cladding joints, joints between brick and frames and brickwork movement joints, and the jobs we see most are movement joints filled with mortar instead of sealant and panel joints letting water in.
Plenty of homes in a town like Northfleet have been extended, and the line where an extension meets the original house is a common leak point. Getting the joint depth right matters as much as the sealant itself.
Whatever the size of the job, you get the same 12-month guarantee in Northfleet and across Kent.
- Where
- Northfleet (DA11)
- Region
- Kent
- Guarantee
- A year, on every job
- Quotes
- A clear price before work begins
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Nearby places to Northfleet
Also in Northfleet
DIY versus a professional finish
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
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.
Landlord and commercial work in Northfleet
In hotels, rooms out of use cost money, so the work can be planned room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
Failed sealant is one of the commonest items on a check-out report. Several properties can go on one quote.
How we quote for external mastic
We quote each job individually. These are the things that affect it:
- When we can work, for business premises
- How many areas need sealing
- Mould in or behind the old joints
- The number and length of the joints
We don’t show prices on the website, because the cost depends so much on the job itself. For a quick quote, please ring 0345 464 0079 or send us an email and we’ll talk you through it.
What we need to know
When you contact us, these details help:
- Where the property is
- The rough size of the job
- The type of property
- Access, such as stairs, a lift or height
We do not publish a price list. Instead, your job gets its own clear quote. To arrange one, phone 0345 464 0079 or email us.
Honest limits
Before you book, it’s worth knowing the limits too:
- Rising or penetrating damp from elsewhere in the wall
- Cracking across the wall rather than at a joint
- Adding movement joints to masonry that has none
If you’re not sure, just ring 0345 464 0079 or email us and we’ll give you a straight answer before you book.
What we seal
- Render & cladding joints
- Brickwork movement joints
- Façade panels
- Concrete & block
- Joints between brick and frames
- Copings & trims
Common questions in Northfleet
Is external mastic in a coastal place like Northfleet any different?
Coastal homes put outside sealant through more weather than inland ones, so the choice of sealant and the preparation matter even more. It’s worth checking the walls that face the sea first.
Do you work for landlords with property near Gravesend station?
Yes, landlords and agents are among the people we work for. Just phone 0345 464 0079 or drop us an email with the address and what needs doing, and we’ll send you a clear quote.
Can you do several jobs on one visit?
Yes, and it often makes sense. Doing several areas at once is usually more efficient.
Will the new joint stand out?
There’s a good range of exterior colours, including greys, browns, whites and stone tones. We pick the one that suits your wall best.
Can you work on commercial sites?
Yes. Hotels, offices and other businesses use us.
Can I do it myself?
Some simple jobs can be done by a careful DIYer. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Do the sealants smell?
Possibly a little. Any smell clears as the sealant cures, and ventilation helps.
Can you seal over the old sealant?
No. Fresh sealant doesn’t stick to old sealant, and anything trapped underneath, including mould and water, stays there. We remove it all first.
What external mastic looks like in Northfleet
Northfleet 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. Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
If you live in an older home near Church of All Saints, an extension built onto an older house moves differently, and the joint between them takes the strain. For site and facilities teams at buildings such as Northfleet Technology College, its movement joints, gutters and trims need looking after like any other building’s. Letting a property close to Gravesend station? Then outside joints that have cracked can let damp into a rental, so check them between lets.
Northfleet is about 5 miles east of Dartford, in Kent. Jobs in Northfleet get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Across Kent, we cover 922 places, Northfleet among them. There’s also a page for London, roughly 20 miles from Northfleet.
Our applicators cover all of the DA11 postcode area for external mastic and the streets around it. That includes homes and businesses on Lawrance Square, London Road and Marks Square and the roads around them. Being close to the A2 and A226, Northfleet is simple for us to get to. If you are just outside Northfleet, we cover Painters Ash (1 mile south-west), Springhead (1 mile west), Windmill Hill (1 mile east), Northfleet Green (1 mile south) and Gravesend (1 mile east). Larger places within reach include Maidstone (14 miles south-east), Dartford (5 miles west), Sevenoaks (13 miles south-west), Swanley (8 miles west), Kings Hill (11 miles south) and Foley Park (13 miles south-east).
Near you in Northfleet
We work in homes and buildings around The Six Bells pub, Saint George's Church of England School and Copperfield Academy. The nearest railway station is Gravesend station, about 1 mile north-east. Other landmarks nearby include Bluewater (3.3 miles west) and Stone Castle (3.1 miles west). Open spaces near Northfleet include Chafford Gorges Nature Park and Sawyers Lake.
How it works
Our applicators work methodically: protection first, then preparation, sealing and a tidy-up. For most jobs that takes a few hours for a handful of joints, longer for a whole elevation. For a job in Northfleet, we need access to where the work is and somewhere nearby to park. For outside work, let us know about side access, gates and any upper-floor joints.
- First, the joints are inspected and the access agreed.
- Every bit of old sealant and any mortar or debris is cut out.
- The faces are brushed clean and primed where the product requires it.
- Backing rod sized to the joint goes in to set the depth.
- We apply the sealant, tool it and check the whole run.
Preparing for the visit
- Plan for the work area to be out of bounds to pets and children
- Mention any sign-in or site rules at work premises
- Let us know about earlier repairs to the joints
Ask for a quote
Every job is quoted individually. Simply call 0345 464 0079 or send us an email and describe the job.
Read more
Why it’s worth doing now in Northfleet
It often makes sense to reseal all the failing joints on an elevation together. They’ve weathered the same way, and access only has to be arranged once. Draughts from a gap round a frame, damp under a sill or water behind a bath panel all start small, and they’re far easier to fix early.
No two jobs are quite the same, so we quote each one individually. Size, access and the product the joint needs all make a difference, and we’ll explain the quote if you ask.
Why Northfleet clients choose us
- More than 20 years in sealant work
- Sanitary silicone with an anti-fungal additive in wet areas
- 180+ five-star Google reviews
- We agree the colour with you first
Read how sealant jobs are priced and our reviews.