Hampshire · England
External & façade joints in Dean, Hampshire
External mastic for Dean and the surrounding area: careful preparation, the right product and tidy work. Ask us for a quick quote.
- Movement joints with cracked, split or missing sealant
- Movement joints filled with mortar instead of sealant
- Cracked joints where brick meets render or frames
About our external mastic in Dean
We are ARBOMaster approved applicators, and each external joint gets a sealant suited to it. Some surfaces need a primer before sealing and we use one wherever it does. We work on copings & trims, façade panels and joints between brick and frames, and the jobs we see most are cracked joints where brick meets render or frames and water getting into walls through failed joints.
In a village or hamlet like Dean, older cottages and farm buildings often stand in the open, so walls and rooflines take the full force of wind and rain. Gutter joints and wall joints there need a sealant that can flex and stay put.
All of our work is guaranteed for twelve months, in Dean and everywhere else we cover.
- Place
- Dean (SO32)
- Wider area
- Hampshire
- Cover
- One year on every job
- Quote
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Should I try it myself first?
If you’re set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
How to look after the new joints
Joint life depends on how it’s used and looked after. We suggest:
- Tell anyone working on the walls about the movement joints
- Get split or bare joints resealed while the damage is small
- Check external joints each spring
- Avoid pressure-washing directly into sealant joints
Follow the cure time we give you before the joint is knocked or disturbed. Most exterior sealants skin fast but take longer to cure right through.
An open movement joint lets rain into the wall every time it pours. That can lead to damp patches, staining and frost damage.
Towns and villages near Dean
More services for Dean
What happens on the day
Good joint work is mostly preparation, and we don’t rush it. Joints are cleaned back and dried before anything new goes in. In total, it normally takes a few hours to a few days, depending on the length of joint and the access. Somewhere like Dean needs a little journey planning: let us know about lanes, gates and parking. Everything for the job comes with us, so a second trip is avoided where possible.
- We start by walking round the building and agreeing the joints and the access.
- We cut out the old mastic and rake out anything in the joint.
- Joint faces are cleaned back and primed if the sealant needs it.
- We fit closed-cell backing rod to control the depth.
- We apply the sealant, tool it and check the whole run.
Getting ready for the visit
- Tell us about any water getting in
- For indoor joints, keep the area dry beforehand if you can
- Let us know about stairs, lifts or work at height
Get a quote
For a quick quote, get us on the phone, or send an email if you’d rather. Tell us about the joints that need doing and we’ll explain what’s involved and send you a clear quote.
Related advice
When to call us in Dean
If plants are growing out of a joint, the sealant has generally failed or was never there. Roots and dirt hold water against the wall and make things worse.
The most common problems we see are:
- Brick movement joints where the sealant has split
- Failed sealant between panels on a façade
- Moss and dirt in joints with no sealant left
- Failed seals between different materials
For an older house near a landmark such as Church of St Peter, an extension built onto an older house moves differently, and the joint between them takes the strain.
What your quote should include
- Is VAT in the price?
- Whether they seal over old material or remove it
- Are they insured?
- How much experience the applicator has
What we cannot put right
Before you book, it’s worth knowing the limits:
- Loose or hollow render, which needs re-rendering
- Damp that isn’t coming from the joint
- Walls that need new movement joints cut into them
Not sure which it is? You can phone 0345 464 0079 or email us and we’ll tell you honestly before booking.
Surfaces we seal
- Brickwork movement joints
- Render & cladding joints
- Concrete & block
- Copings & trims
- Joints between brick and frames
- Façade panels
Dean buildings and 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.
Schools such as Bishops Waltham Infant School are buildings too, and larger buildings have long runs of movement joint that eventually need resealing. Letting a property close to Botley station? Then split movement joints are easy to miss on a rental until damp shows inside.
Dean is about 6 miles north-east of Hedge End, in Hampshire. Homes, rented property, offices and hotels in Dean is covered for external mastic, old or new, large or small. The work is guaranteed for a year. Dean is one of 683 towns and villages in Hampshire where we work. You can also see our page for Southampton, about 9 miles away.
Work in SO32 is quoted and booked the same way as anywhere else. If you need external mastic at a property on Dean Lane, Little Ashton Lane and Limekiln Lane or anywhere close by, our applicators can take on the job. If you are just outside Dean, we cover The Hangers (1 mile east), Upper Swanmore (2 miles south-east), Swanmore (2 miles south), Hill Grove (2 miles south-east) and Droxford (3 miles east). Within a short drive, we also cover Winchester (8 miles north-west), Gosport (12 miles south), Havant (12 miles south-east), Eastleigh (6 miles west), Fareham (8 miles south) and Horndean (9 miles south-east).
Landmarks near Dean
Around Dean, our work takes us to homes and buildings near Swanmore College of Technology. For rail, the closest station is Botley station, roughly 4.6 miles south-west. Well-known places in the area include Bishop's Waltham Museum (1.4 miles south-west). The countryside around Dean includes Bishops Waltham Branch LNR and Beacon Hill.
Common questions in Dean
Can you do external mastic in Dean?
Yes. Our work covers London and the South East, and Dean is part of that. Just phone 0345 464 0079 or drop us an email with a few details of the job.
Will you come out to Dean?
Yes. Dean is within the area we cover, which takes in towns, villages and rural addresses. We work across London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Why do you put foam in the joint first?
Closed-cell backing rod sets the depth of the sealant and stops it sticking to the back of the joint. That way it bonds to the two sides only and can stretch.
Where are you based?
We’re based in Crawley, West Sussex, and we cover South East England, London and all of Scotland.
How do I get a quote for external mastic in Dean?
Size, access and the old material all affect the cost. Ask us for a quote and we’ll talk you through it.
How long does external mastic last?
It varies with how exposed the wall is and how much the joint moves. Look for splits, hardening or edges coming away.
Is it OK to fill a movement joint with cement?
No. Rigid materials can’t move with the wall. If it has already been filled, we can normally cut it out and reseal it.
Are you ARBOMaster approved?
Yes. We hold ARBOMaster approved applicator status.
Surface by surface
Cladding and façade panels
If the façade has a specified sealant, that’s what we use or an approved alternative. Tell us what the building has when you get in touch.
Joints between dissimilar materials
Where a frame or panel meets masonry, water often finds a way in. The old joint is removed and a sealant that bonds to both sides goes in.
Work for landlords, hotels and businesses
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Keeping joints in good order is simple maintenance.
Businesses can book us for washrooms, kitchens, offices and more. For commercial premises, we can talk through working times when we quote.