Kent · England
External Mastic in Waltham
External mastic for Waltham, by sealant specialists with 20+ years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Moss and dirt in joints with no sealant left
- Failed sealant between panels on a façade
- Sealant pulling away from one side of the joint
External mastic in Waltham, done properly
Joints between dissimilar materials, like brick against render or concrete against a steel frame, see movement from both sides. A flexible sealant bridges the two where mortar or filler would crack. Typical jobs include joints with sealant missing in places and cracked joints where brick meets render or frames, across render & cladding joints, brickwork movement joints and copings & trims.
Outside joints can only be sealed when they’re dry, so work in Waltham is booked around the forecast. Let us know about access to every wall, plus any garages or outbuildings.
We stand behind the work with a one-year guarantee.
- Where
- Waltham (CT4)
- Wider area
- Kent
- Guarantee
- A year, on every job
- Quotes
- A clear quote up front
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Work for landlords, hotels and businesses
For anyone letting property in or around Waltham, jobs at different addresses can be quoted together. Just tell us the addresses and what each one needs, and photos by email help.
Landlords and letting agents in Waltham can book us as well as homeowners. Resealing between tenancies is a simple way to keep a property in good order.
Other services in Waltham
Waltham questions
Do you cover Waltham for external mastic?
Yes. Our work covers London and the South East, and Waltham is part of that. Just call 0345 464 0079 or email us with a few details of the job, and we’ll give you a clear price.
Do you work for landlords with property near Chilham station?
Yes, landlords and agents are among the people we work for, and several properties can go on one quote. You can ring 0345 464 0079 or send us an email with the details for a clear quote.
Is it OK to seal over old sealant?
No, because it fails. The old sealant always comes out first, so the new sealant bonds properly.
Can you do several jobs on one visit?
Yes. More than one area can be quoted together.
Are you insured?
Yes. Full insurance covers our work.
How do you reach high-level joints?
It depends on the building. We work on joints that can be reached safely. Give us some details and we’ll confirm the access.
Do you seal joints where cladding meets other materials?
Yes. Joints between dissimilar materials are a big part of external work. The sealant is chosen to bond to both sides, primed where needed.
Do you do commercial work?
Yes. Hotels, offices and other businesses use us, and we’re fully insured.
Waltham buildings and 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.
Letting a property close to Chilham station? Then failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Waltham is about 6 miles south-west of Canterbury, in Kent. Every kind of property in Waltham can book us for external mastic. The work is guaranteed for a year. Our area takes in 922 places across Kent. There’s also a page for Chelmsford, roughly 44 miles from Waltham.
Our applicators cover all of CT4 for external mastic and the streets around it. Whether your property is on Church Lane, Richdore Road and Kake Street or a nearby road, we can help. Neighbouring places we cover for external mastic include Stelling Minnis (2 miles east), Bossingham (2 miles east), Stowting Common (4 miles south), Stowting (4 miles south) and Rhodes Minnis (4 miles south-east). Further out, we also cover Ashford (8 miles south-west), Canterbury (6 miles north-east), Dover (13 miles east), Folkestone (10 miles south-east), Whitstable (11 miles north) and Faversham (10 miles north-west).
What’s near Waltham
We work in homes and buildings around Compasses Inn. The nearest railway station is Chilham station, about 3.7 miles north-west of the centre. Nearby you will also find Chilham Castle (4.1 miles north-west) and Kent and Canterbury Hospital (5.5 miles north-east).
Why it’s worth doing now in Waltham
The longer a joint stays open, the more water the wall takes in. In cold weather, frost can damage wet brick and render around the joint, so the problem grows beyond the joint itself. Older cottages and farmhouses around Waltham can have timber floors and frames, and water through a failed joint can rot timber if it’s left.
What it costs depends on the size of the job, how much old material has to come out and access to the work. You will have a clear quote before any work starts, so you know where you stand.
Why choose Mr Mastic in Waltham
- Colour picked to suit the job
- Domestic, commercial and hotel work
- A choice of colours where the product allows
- ARBOMaster approved applicator
Read what affects the cost and our reviews.
DIY versus a professional finish
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and doesn’t move well, and getting the depth right matters as much as the look.
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it does not work out, we can still put it right.
What we cannot put right
Some problems need a builder, plumber or other trade rather than us:
- Structural movement, which needs a surveyor or engineer
- Render that’s blown, hollow or coming away
- Cracking across the wall rather than at a joint
Not sure which it is? You can ring 0345 464 0079 or send us an email and we’ll tell you honestly before you book.
What we seal
- Brickwork movement joints
- Copings & trims
- Joints between brick and frames
- Façade panels
- Render & cladding joints
- Concrete & block
Surface by surface
Copings and trims
A failed coping joint lets water into the top of the wall. Resealing them is a small job that protects a lot.
Brickwork movement joints
People sometimes point up a brick movement joint by mistake. If that is happened, we rake it out and reseal it properly if the joint can be cleared.
Do you need external mastic in Waltham?
UV, rain and frost all age exterior sealant. Over the years it hardens, cracks on the surface and loses its give, so the next time the wall moves, it splits or pulls away.
Keep an eye out for these signs:
- Sealant pulling away from one side of the joint
- Damp patches traced to an open external joint
- Movement joints filled with mortar instead of sealant
- Brick movement joints where the sealant has split
Homes close to Church of St Bartholomew include some older properties, and old and new materials meet at the roofline and walls, which is where sealant earns its keep.
What your quote should include
- What guarantee comes with the work
- What happens if the job turns out different
- Is VAT in the price?
- How the surfaces are prepared before sealing
What happens on the day
At the end, we look at the finished work together and tell you how long to leave it. The visit itself normally takes a few hours for a handful of joints, longer for a whole elevation, depending on how much there is to do. For a village or hamlet like Waltham, the journey is planned in advance: tell us about narrow lanes, gates, long drives and where we can park. Everything for the job comes with us, so a second trip is avoided where possible.
- First we look over the joints with you, agree which to renew and talk through access.
- We cut out the failed sealant and rake out any dirt or growth.
- The joint faces are cleaned and primed where the sealant needs it.
- We push in closed-cell backing rod so the sealant is the right depth and bonds to the sides only.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Before we arrive
- Mention any sign-in or site rules at work premises
- For indoor joints, keep the area dry beforehand if you can
- Keep pets and children clear of the area while we work
Getting a quote
Asking for a quote is easy: tell us what needs doing and where. Photos by email help us understand the job, and we will take it from there.