Kent · England
External Mastic in Kemsing
Sealing brickwork movement joints, render, cladding and façade joints for Kemsing, backed by a one-year guarantee. Call for a quick quote.
- Sealant that has lost its bond to the brick or render
- Movement joints with cracked, split or missing sealant
- Movement joints filled with mortar instead of sealant
How we handle external mastic in Kemsing
For buildings in Kemsing, we reseal external joints of all kinds, from brick movement joints to cladding panels. Every joint gets the same careful preparation: clean joint faces and the right depth. We work on joints between brick and frames, copings & trims and brickwork movement joints, and people most often call us about leaking joints around cladding and façade panels and damp patches traced to an open external joint.
In a smaller place like Kemsing, some homes face open ground, and walls and rooflines facing the weather take the worst of it. Joints on those sides are usually the first to go.
Our work is backed for twelve months.
- Place
- Kemsing (TN15)
- Wider area
- Kent
- Guarantee
- 12 months on all our work
- Quotes
- A clear quote up front
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
What we are called out for in Kemsing
A lot of failed joints come down to preparation: dusty or wet faces, no primer where one was needed, or old sealant left in. The new sealant then lets go long before it should.
Look out for these signs:
- Sealant that has lost its bond to the brick or render
- Old sealant gone brittle and cracked
- Movement joints with cracked, split or missing sealant
- Panel joints letting water in
Managing a site like Kemsing Primary School? Then larger buildings have long runs of movement joint that eventually need resealing.
What your quote should include
- Is the old sealant removed completely?
- What happens if they find a problem under the old sealant
- Is VAT in the price?
- Whether the sealant suits the joint
Places near Kemsing
Other services in Kemsing
What affects the quote in Kemsing
Your quote is based on your job. We take into account:
- How many areas need sealing
- When we can work, for business premises
- Whether the work is at height
- How much old sealant there is and how hard it is to remove
A few things move the cost up or down: the old material and how easily it comes out, whether mould needs treating, and whether we need extra access for height. Your quote takes all of that into account.
Helping us quote
Before you ask for a quote, have a think about:
- How many joints, rooms or windows are involved
- If it’s domestic, commercial or a hotel
- What the problem is, such as mould, gaps, leaks or cracking
- Photos by email, if that is easy
Want a quote for external mastic? Please call 0345 464 0079 or drop us an email with a few details. We will explain what we’d do and give you a clear price before any work starts.
DIY versus a professional finish
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and getting the depth right matters as much as the look.
If you’ve already had a go yourself, that’s fine. We cut it out and start again, so just mention it when you contact us.
Questions from Kemsing
Do you cover smaller places like Kemsing?
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.
Do you work for landlords with property near Otford station?
Yes, rental work is part of what we do. You can phone 0345 464 0079 or send us an email with the address and a few details, and we will give you a fixed price before work begins.
Will the old sealant be removed?
Yes, always, and completely. New silicone does not stick to old silicone, so any old material comes out before anything new goes in.
Where is Mr Mastic based?
We work from Crawley. Our applicators cover Kemsing.
Can you seal joints between two different materials?
Yes. Materials like render, brick, metal and uPVC all move differently, so the joint between them must be flexible. The sealant is matched to both sides.
Do you guarantee your work?
Yes. Every job comes with a one-year guarantee.
Is it worth trying it myself?
You can, for simple jobs. Preparation is everything: all the old sealant out, and a clean, dry joint. If it does not work out, we can redo it.
How much does external mastic cost in Kemsing?
Size, access and the old material all affect the cost. Call for a quick quote.
Kemsing buildings and the weather
Historic houses like Knole House (about 2.8 miles south) are a reminder that the area around Kemsing has older buildings as well as new. 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, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
For landlords with property near Otford station, failed wall and movement joints let damp in, so they’re worth checking between tenancies. In the older streets around Church of St Mary, an extension built onto an older house moves differently, and the joint between them takes the strain.
Kemsing is about 2 miles north-east of Sevenoaks, in Kent. Homes, rented property, offices and hotels in Kemsing is covered for external mastic, old or new, large or small. The work is guaranteed for a year. Across Kent, we cover 922 places, and Kemsing is one of them. London is on our list too, around 19 miles away.
We cover every part of TN15 for external mastic and the streets around it. Streets in the area include High Street, Copperfields Walk and Childsbridge Lane, and we cover them all. Neighbouring places we cover for external mastic include Cotman's Ash (1 mile north-east), Heaverham (2 miles east), Woodlands (2 miles north-east), Romney Street (2 miles north) and Knatts Valley (2 miles north-east). We also work in nearby towns such as Maidstone (14 miles east), Dartford (9 miles north), Royal Tunbridge Wells (12 miles south), Gravesend (11 miles north-east), Tonbridge (8 miles south) and Northfleet (10 miles north-east).
Local landmarks in Kemsing
In Kemsing, that means homes and buildings near St Michael's Preparatory School, Knole Academy and Kemsing Down. The nearest railway station is Otford station, roughly 1 mile north-west of the centre. Well-known places in the area include Kemsing Castle Bank (0.5 miles east) and Otford Heritage Centre (1 mile west). Not far away are Dryhill Nature Reserve.
Keeping the joints in good condition
Simple care keeps the joints in good condition. We recommend:
- Avoid pressure-washing directly into sealant joints
- Clear growth from the base of walls and joints
- Check external joints each spring
- Never let anyone fill a movement joint with mortar
Have a quick look at the joints each spring. Splits, gaps at the edges or plants in the joint are early warning signs.
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 it’s worth resealing at the first signs.
Work for landlords, hotels and businesses
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements and we’ll give you a quote.
If you manage several properties in or around Kemsing, several properties can be quoted together. Send us the addresses and the work at each.
Why act early in Kemsing
Sealing over the top of old mastic doesn’t hold for long. New sealant does not bond well to old, weathered sealant, so we always take the old sealant out. In a smaller place like Kemsing, wherever a wall is exposed, a failed outside joint is a real source of damp. Indoors, a failed seal lets water into floors and panels as it would anywhere.
The cost depends on the size of the job, how hard the old material is to remove and access to the work. You will have a clear quote before any work starts, so you know where you stand.
Why us?
- Arbo and Everbuild products
- Sealant colour chosen to suit
- An ARBOMaster approved applicator
- Old sealant always removed completely
See our cost guide and customer reviews.
What we do, step by step
On the day, we look over the joints with you first. Surfaces next to the work are protected before work begins. Most jobs take a few hours to a few days, depending on the length of joint and the access. In a smaller place like Kemsing, parking is seldom the issue; lanes, gates and long drives are worth mentioning. If the job is outside, tell us about side access and how high the joints are.
- We look at every joint and agree a colour to suit the wall.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- Primer is applied wherever the sealant needs it.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
How to prepare
- Move anything stored near the joints
- Tell us if parking is tricky
- Keep pets and children clear of the area while we work
Getting a quote
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is. Whenever you’re ready, ring 0345 464 0079 or send us an email.