Kent · England
External Mastic in Barnes Cray
Problem with your movement joints in Barnes Cray? We cut out the old, prepare the joints and apply the right sealant.
- Sealant that has lost its bond to the brick or render
- Leaking joints around cladding and façade panels
- Damp patches traced to an open external joint
Should I try it myself first?
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
External mastic in Barnes Cray, done properly
Failed sealant is cut out, the depth set with closed-cell backing rod, and the joint resealed with a low-modulus sealant made for outside. We pick a colour that sits well with the wall so the line blends in. If you’re dealing with brick movement joints where the sealant has split and rigid filler in a joint that should flex, we can help, whatever the surface.
In a smaller place like Barnes Cray, some homes face open ground, and walls and rooflines facing the weather take the worst of it. Joints on those sides are normally the first to go.
All our work comes with a 12-month guarantee, wherever you are in Kent.
- Place
- Barnes Cray (DA1, DA8)
- Wider area
- Kent
- Guarantee
- 12 months on all our work
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Questions from Barnes Cray
I let a flat near Slade Green station. Can you help?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. Just call 0345 464 0079 or drop us an email with the address and what needs doing, and we will give you a clear quote.
Do you cover Barnes Cray for external mastic?
Yes. We work across London and the South East, and Barnes Cray is part of that. Just call 0345 464 0079 or email us with a few details of the job.
Are you fully insured?
Yes. We are fully insured, with over 20 years’ experience in sealant work.
Why is there a gap in my brick wall?
Walls move with heat, cold and moisture, so long walls have planned gaps to take that movement. It’s closed with backing rod and a flexible sealant.
What sealant do you use?
Each joint gets the product that suits it. Where it moves, gets wet or faces the weather makes a difference, and we’ll explain our choice.
Do you remove the old sealant?
Yes. Sealing over old sealant is the main reason resealing fails early, so we never do it.
Can you do several jobs on one visit?
Yes. Just list everything you need and we’ll quote it together.
Will you leave a mess?
Not at all. We work neatly, protect the area around the joints and tidy up afterwards.
Why deal with it now?
It often makes sense to reseal all the failing joints on an elevation together. Joints of the same age tend to fail together and it means sorting access once. Around Barnes Cray, water from a failed joint in an older home can soak into timber and plaster, which is far harder to put right than the sealant itself.
Some things make a job bigger or smaller: the old material and how easily it comes out, any mould to treat, and whether we need extra access for height. Your quote takes all of that into account.
Why Barnes Cray customers choose us
- Domestic, commercial and hotel work
- Trusted Arbo and Everbuild sealants
- We agree the colour with you first
- Colour picked to suit the job
Read our cost guide or customer reviews.
How it works
Before we leave, we go over the finished joints with you. The work normally takes a few hours to a few days, depending on the length of joint and the access, depending on the size of the job. A visit to Barnes Cray is planned like any other: the time, the access and where to park are agreed in advance. If the work is outside, the weather plays a part, as sealant needs a dry surface.
- First, the joints are inspected and the access agreed.
- Every bit of old sealant and any mortar or debris is cut out.
- Joint faces are cleaned back and primed if the sealant needs it.
- Backing rod sized to the joint goes in to set the depth.
- The exterior sealant is applied, tooled and checked along its length.
Preparing for the visit
- Clear the area around the work
- Tell us about any water getting in
- Mention any tricky access
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 add photos by email if you can.
Read more
What external mastic looks like in Barnes Cray
With historic houses such as Hall Place and Gardens (about 1.7 miles south-west) nearby, there’s older building stock in the area around Barnes Cray as well as newer homes. In older buildings, 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, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Schools such as Haberdashers' Aske's Crayford Academy are buildings too, and larger buildings have long runs of movement joint that eventually need resealing. Letting a property close to Slade Green station? Then failed wall and movement joints let damp in, so they’re worth checking between tenancies. For an older house near a landmark such as Christ Church, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
Barnes Cray is about 2 miles north-west of Dartford, in Kent. Whether you’re in the middle of Barnes Cray or further out, we cover external mastic for every kind of property. We cover 922 towns and villages across Kent, from the larger towns to small villages. We also work in London, around 13 miles away.
Jobs for external mastic in DA1 and DA8 works the same way as everywhere else we cover. If you need external mastic at a property on Stour Road, Wilmot Road and Maiden Lane or anywhere close by, we can help. We also cover the places around Barnes Cray: Slade Green (1 mile north), North End (1 mile north), Crayford (1 mile south-west), Barnehurst (1 mile west) and Bexley Riverside (1 mile north-west). We also work in nearby towns such as Sevenoaks (12 miles south), Gravesend (8 miles east), Northfleet (7 miles east), Swanley (4 miles south), Swanscombe (4 miles east) and Windmill Hill (8 miles east).
Around Barnes Cray
We work in homes and buildings around Braeburn Park, Bird in Hand pub and Holy Trinity Church of England Primary School and the streets around them. The closest station to Barnes Cray is Slade Green station, about 0.7 miles north. Other landmarks nearby include West Hill Hospital (1 mile south-east) and Dartford Library (1.4 miles south-east). Open spaces near Barnes Cray include Wansunt Pit.
Nearby places to Barnes Cray
More services for Barnes Cray
What affects the quote in Barnes Cray
The quote reflects the job in front of us. We take into account:
- How easy the joints are to reach
- The number of rooms or windows
- When we can work, for business premises
- Whether there’s mould to deal with
Doing several joints on one visit normally makes better use of the time than several visits. We’ll send you a clear quote for the lot.
What to tell us for a quote
When you call or email, it’s useful to know:
- Access, such as stairs, a lift or height
- Where the job is, and your postcode
- How many joints, rooms or windows are involved
- Whether it has been sealed before
For a quick quote, get us on the phone, or email us if that’s easier. Tell us about the joints that need doing and we will explain what’s involved before giving you a price.
For landlords and businesses
We work for landlords and letting agents as well as homeowners. Sealant work between tenants keeps a property looking cared for.
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance.
Different surfaces, different methods
Copings and trims
A failed coping joint lets water into the top of the wall. Sealing them early saves the wall below.
Brickwork movement joints
Brick movement joints are often mistaken for a missing mortar line. If that is happened, we rake it out and reseal it properly if the joint can be cleared.
Keeping the joints in good condition
Good habits help new joints last longer. Our tips:
- Wash walls gently around the sealant
- Get split or bare joints resealed while the damage is small
- Show decorators and builders where the movement joints are
- Clear growth from the base of walls and joints
Make sure anyone working on the wall later knows where the movement joints are. They should be kept open and resealed, not filled.
Leave a failed movement joint and water keeps getting into the wall. Over time it can mean damp inside, stained render or frost-damaged brick, all bigger jobs than a reseal.