Hampshire · England
External & façade joints in Southwick, Hampshire
External mastic for Southwick and the surrounding area: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Moss and dirt in joints with no sealant left
- Joints with sealant missing in places
- Failed seals between different materials
How we quote for external mastic
You will get a clear quote before work begins. It’s based on:
- The number of rooms or windows
- Which sealant suits the joint
- Whether the work is at height
- How much old sealant there is and how hard it is to remove
Instead of a standard rate, we look at what your job involves: how many joints, what’s in them now and how we reach them. The price is agreed before we begin.
What we need to know
A few details help us give you an accurate quote. When you get in contact, it helps to mention:
- Pictures of the joints, sent by email
- Roughly how big the job is
- Whether it’s a home or a business
- Where the job is, and your postcode
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 email photos if that’s easy.
External mastic in Southwick
As ARBOMaster approved applicators, we choose exterior sealants to suit the joint and the surfaces. Some surfaces need a primer before sealing, and we do not skip that step. We work on copings & trims, façade panels and joints between brick and frames, and the jobs we see most are rigid filler in a joint that should flex and water getting into walls through failed joints.
In a village or hamlet like Southwick, 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.
We stand behind the work with a one-year guarantee, so you’re covered after we have gone.
- Place
- Southwick (PO17)
- Region
- Hampshire
- Guarantee
- 12 months on all our work
- Quote
- A clear price before work begins
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Also near Southwick
What else we do in Southwick
The process
Most of a good job is in the preparation, and we do not rush it. Every joint is cleaned and dried before new material goes in. In total, it usually takes a few hours for a handful of joints, longer for a whole elevation. For a village or hamlet like Southwick, 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.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- The faces are brushed clean and primed where the product requires it.
- Backing rod sized to the joint goes in to set the depth.
- The exterior sealant is applied, tooled and checked along its length.
Getting ready for the visit
- Let us know if you’ve seen damp or leaks
- Tell us if parking is tricky
- Plan for the work area to be out of bounds to pets and children
Get a quote
We quote each job on its own, so the first step is telling us about yours. Simply phone 0345 464 0079 or drop us an email and describe the job and send pictures if you have them.
Related advice
Looking after it afterwards
So the new joints stay in good condition:
- Show decorators and builders where the movement joints are
- Keep high-pressure jets off the joints
- Check the sealant is paintable before painting near it
- Make sure movement joints aren’t pointed over
Do not paint over the new sealant unless we’ve said the product is paintable. Paint can crack on a flexible joint and spoil the finish.
If you can see gaps, plants or bare sections in a joint, have it checked. Early work is quicker and leaves a better finish.
Different surfaces, different methods
Copings and trims
Metal and stone copings both move with temperature, so a flexible sealant suits them best.
Render joints
Render has movement joints and stop beads that need sealing. They’re resealed in a sealant that suits the render.
DIY versus a professional finish
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 sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Questions from Southwick
Is external mastic in a coastal place like Southwick any different?
Coastal weather is harder on outside sealant: there’s more wind-driven rain and, closer to the shore, salt in the air. Choosing the right sealant for the frame and wall, laid at the right depth, helps it last.
Can you help a landlord with a rental near Portchester station?
Yes, rental work is part of what we do. You can call 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.
What do you put in the joint?
We choose the sealant for the joint, not the other way round. Movement, water and weather all affect the choice, and we’ll tell you what we’re using.
Do you cover Southwick?
Yes. We cover Southwick and the rest of Hampshire, as part of our work across South East England, London and Scotland. For a quote, call 0345 464 0079 or email us.
Can you do several jobs on one visit?
Yes. Just list everything you need and you will get one quote.
How long should I leave it?
Most sealants are touch-dry well before they’re fully cured. We will tell you how long to leave the joint before we leave.
Is it worth trying it myself?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. Most DIY failures come from sealing over old material, wet joints or too much sealant.
Do you have insurance?
Yes. Mr Mastic is fully insured, with over 20 years’ experience in sealant work.
Landlords, agents and businesses in Southwick
We also work for property managers and facilities teams. We can quote a run of properties together, and we are fully insured for the work.
Hotels need rooms back in use, so the work can be planned room by room. Hotel work is part of what we do, alongside homes and businesses.
When something else is needed
A few problems are outside what sealant work can do:
- Render that’s blown, hollow or coming away
- Cracks in the bricks or render themselves, away from the joints
- Adding movement joints to masonry that has none
Not sure which it is? You can ring 0345 464 0079 or email us and we’ll tell you honestly.
Surfaces we seal
- Copings & trims
- Concrete & block
- Brickwork movement joints
- Render & cladding joints
- Façade panels
- Joints between brick and frames
External mastic in Southwick: local notes
Southwick is within about 2 miles of the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. That is hard on movement joints and outside wall joints, especially on the side facing the sea. Rainfall in the South East is lower than in much of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
If you live in an older home near Church of St James Without the Priory Gate, the joints between older walls, newer extensions and the roofline need a sealant that can move. For landlords with property near Portchester station, split movement joints are easy to miss on a rental until damp shows inside. Schools such as King Richard School are buildings too, and its movement joints, gutters and trims need looking after like any other building’s.
Southwick is about 3 miles west of Purbrook, in Hampshire. Anywhere in PO17, we can carry out external mastic at your property. 683 places in Hampshire are on our list.
Jobs for external mastic in PO17 works the same way as everywhere else we cover. If you need external mastic at a property on High Street, North Road West and Castle Road or a nearby road, our applicators can take on the job. If you’re just outside Southwick, we cover Boarhunt (1 mile west), North Boarhunt (2 miles north-west), Portchester (2 miles south), Hundred Acres (3 miles north-west) and North Fareham (3 miles west). Within a short drive, we also cover Gosport (5 miles south), Havant (5 miles east), Eastleigh (12 miles north-west), Fareham (4 miles west), Horndean (5 miles north-east) and Chandler's Ford (14 miles north-west).
What’s near Southwick
Around Southwick, our work takes us to homes and buildings near Red Lion Inn and the streets around them. Southwick’s nearest station is Portchester station, roughly 1.9 miles south of the centre. Other landmarks nearby include Portchester Castle (2.6 miles south) and Fareham Shopping Centre (3.2 miles south-west). For a walk, there’s Portsdown Hill and St Clair's Meadow.