Kent · England
External & façade joints in Platt, Kent
Professional external mastic in and around Platt, with old sealant always removed completely.
- Movement joints filled with mortar instead of sealant
- Weathered mastic that no longer stretches
- Sealant that has lost its bond to the brick or render
About our external mastic in Platt
For buildings in Platt, we reseal external joints of all kinds, from brick movement joints to cladding panels. The preparation is the same whatever the wall: clean, sound faces and a controlled depth. Common call-outs are for leaking joints around cladding and façade panels and weathered mastic that no longer stretches, on brickwork movement joints, joints between brick and frames and copings & trims.
Outside joints can only be sealed when they’re dry, so work in Platt is booked around the forecast. Let us know about access to every wall, plus any garages or outbuildings.
You are covered for a year from the day we finish. If anything is not right with it, phone 0345 464 0079 or send us an email.
- Location
- Platt (TN15)
- Wider area
- Kent
- Cover
- A year, on every job
- Quotes
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Aftercare tips
Good habits help new joints last longer. A few tips:
- Leave the joints unpainted unless we’ve said otherwise
- Show decorators and builders where the movement joints are
- Deal with leaking gutters that soak the joints below
- Do not let climbing plants root in the sealant
Make sure anyone working on the wall later knows where the movement joints are. They should be kept open and resealed, not filled.
Water getting behind cladding or render can go unnoticed for a long time. When it finally shows inside, the joint may have been open for years so early resealing is worth it.
When something else is needed
Before you book, it’s worth knowing the limits:
- Cracking across the wall rather than at a joint
- Rising or penetrating damp from elsewhere in the wall
- Render that’s blown, hollow or coming away
If in doubt, phone 0345 464 0079 or email us and we’ll say what we think.
What we seal
- Joints between brick and frames
- Façade panels
- Copings & trims
- Brickwork movement joints
- Render & cladding joints
- Concrete & block
Places near Platt
What else we do in Platt
What we do, step by step
At the end, we look at the finished work together and explain the cure time. The work normally takes anything from a few hours to several days, depending on the building, depending on the amount of work. For a village or hamlet like Platt, the journey is planned in advance: tell us about narrow lanes, gates, long drives and where we can park. We bring what the job needs, so it can be finished in one trip where possible.
- We start by checking each joint, agreeing the ones to redo and how we will reach them.
- Old sealant and any debris are cut and raked out.
- We clean both faces of the joint and prime them where the product calls for it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Preparing for the visit
- Mention if the joints have been sealed before
- On commercial sites, let us know about site rules
- Clear the area around the work
Ask for a quote
We quote each job on its own, so the first step is telling us about yours. Just ring 0345 464 0079 or send us an email with the details.
Related advice
FAQs for Platt
Is Platt in your area for external mastic?
Yes, Platt is within the area we cover. We work across London and the South East. You can call 0345 464 0079 or email us and tell us what needs doing, and we will give you a clear price.
Can you help a landlord with a rental near Borough Green & Wrotham station?
Yes. We work for letting agents and landlords as well as householders. Just phone 0345 464 0079 or send us an email with the address and what needs doing, and we will give you a clear quote.
What do you put in the joint?
The product depends on the job: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. We use products from Arbo and Everbuild.
Is it messy?
No. We protect the surfaces around the joints, and we tidy up before we go.
Do you do commercial work?
Yes. We’ve worked for hotels, offices and other businesses, and we’re fully insured.
Are you an approved applicator?
Yes. We are an ARBOMaster approved applicator, the approved applicator scheme for Arbo sealants.
When will the joints need doing again?
That varies with the weather the wall faces, how much it moves and the sealant used. Sealant is a maintenance item, so check the joints once a year and renew it when it starts to fail.
How long does external mastic take?
That depends on how much there is to do, but as a guide it takes a few hours for a handful of joints, longer for a whole elevation. We’ll give you a better idea when we quote.
How we quote for external mastic
The quote reflects the job in front of us. We take into account:
- Access and height
- Any working-time requirements on site
- The number and length of the joints
- Whether there’s mould to deal with
A failed joint rarely gets cheaper to fix by waiting, because water and mould keep working on it. If you’re unsure, ring 0345 464 0079 or email us and we’ll give you an honest view and a quote.
What we need to know
When you call or email, it’s useful to know:
- Any access issues, like height or stairs
- If someone has resealed it before
- What’s wrong with the joints now
- Where the property is
To get a quote, ring 0345 464 0079 or email us and tell us where the job is and what the problem looks like. You will have a clear quote before any work starts.
Landlords, agents and businesses in Platt
For anyone letting property in or around Platt, jobs at different addresses can be quoted together. Just tell us the addresses and what each one needs, and photos by email help.
In hotels, rooms out of use cost money, so we plan the work room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
Signs you need external mastic in Platt
Weeds, moss and debris in a joint are a sign the sealant has gone. Roots and dirt hold water against the wall and speed up the damage.
People usually contact us when they notice one of these:
- Plants rooting in failed movement joints
- Damp patches traced to an open external joint
- Joints with sealant missing in places
- Leaking joints around cladding and façade panels
Homes close to Church of St Mary include some older properties, and the joints between older walls, newer extensions and the roofline need a sealant that can move.
Before booking anyone
- How long to leave it before use
- Whether you can choose the colour
- How the joint is cleaned and prepared
- What insurance they hold
What external mastic looks like in Platt
With historic houses such as Old Soar Manor (about 1.9 miles south) nearby, there’s older building stock in the area around Platt 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. 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.
Managing a site like Platt Church of England Voluntary Aided Primary School? Then larger buildings have long runs of movement joint that eventually need resealing. For landlords with property near Borough Green & Wrotham station, split movement joints are easy to miss on a rental until damp shows inside.
Platt is about 6 miles east of Sevenoaks, in Kent. If you need external mastic in Platt, please ring 0345 464 0079 or send us an email for a quick quote. We are based in Crawley and cover Kent, Platt included. Platt is one of 922 towns and villages in Kent where we work for external mastic. London is on our list too, about 23 miles from Platt.
Here we cover the TN15 postcode area for external mastic. Local streets include St Mary's Close, Grange Road and Platt Common, all of which we cover. If you are just outside Platt, we cover Comp (1 mile south-east), Borough Green (1 mile west), Crouch (1 mile south-west), Wrotham Heath (1 mile north-east) and Basted (1 mile south-west). Larger places within reach include Maidstone (9 miles east), Dartford (12 miles north-west), Sevenoaks (6 miles west), Royal Tunbridge Wells (11 miles south), Gravesend (10 miles north) and Tonbridge (7 miles south).
Around Platt
We work in homes and buildings around Wrotham School, The Blue Anchor pub and Wrotham School, among other places. The nearest railway station is Borough Green & Wrotham station, roughly 0.9 miles west. Nearby you will also find Ightham Court (1.8 miles west) and Beechin Wood Archery Museum (under half a mile south-east).
Why deal with it now?
Sealing over the top of old mastic doesn’t hold for long. New sealant doesn’t bond well to old, weathered sealant, so we always take the old sealant out. In a small place like Platt, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
Commercial jobs are quoted on the same basis as homes: how much there is to do, how we reach it and what it needs, plus any working-time requirements on site. Call for a quick quote and we will explain what it covers.
What you get with us
- An ARBOMaster approved applicator
- Fully insured
- Anti-fungal sanitary silicone in wet areas
- We never seal over old sealant
See what affects the cost or our reviews.