Hampshire · England
External & façade joints in Newtown, Hampshire
External mastic in Newtown from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Joints pointed up with cement by mistake
- Movement joints with cracked, split or missing sealant
- Failed seals between different materials
External mastic for homes and businesses in Newtown
Short cuts in external joints show up within a season or two. New sealant over old, joints packed with mortar and beads with no backing rarely last long. We strip the joint back and start again. If you have failed seals between different materials and plants rooting in failed movement joints, we can put it right.
Somewhere as small as Newtown, homes and farm buildings often face open ground, where walls and rooflines take the weather head on. Joints on those walls need a sealant that moves with the building and stays in place.
Big or small, you get the same one-year guarantee in Newtown and across Hampshire.
- Where
- Newtown (PO17)
- Wider area
- Hampshire
- Guarantee
- 12 months on all our work
- Quote
- A clear price before work begins
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
How it works
Once we’re on site, we check the joints match what you told us. If anything is different, we explain it before carrying on. After that, the work takes a few hours to a few days, depending on the length of joint and the access. Somewhere as small as Newtown, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- Each joint is checked and the colour of the new sealant agreed.
- 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.
- We gun in low-modulus sealant and tool it neatly.
Before we arrive
- Clear the area around the work
- Mention any sign-in or site rules at work premises
- Tell us if parking is tricky
How to get a quote
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is. When it suits you, ring 0345 464 0079 or drop us an email.
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What external mastic looks like in Newtown
The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Rented homes near Portchester station change hands often, and split movement joints are easy to miss on a rental until damp shows inside. For site and facilities teams at buildings such as Newtown Soberton Infant School, movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
Newtown is about 5 miles north-west of Waterlooville, in Hampshire. Anywhere in PO17, our applicators can take on external mastic. Across Hampshire, we cover 683 places, and Newtown is one of them. You can also see our page for Portsmouth, about 8 miles away.
We work across the PO17 postcode area for external mastic and the streets around it. If you need external mastic at a property on Church Road, Hundred Acres Road and Ingoldfield Lane or a nearby road, our applicators can take on the job. Neighbouring places we cover for external mastic include Southend (1 mile north-east), Soberton Heath (1 mile north), Hoe Gate (1 mile east), Hipley (1 mile south-east) and Woodend (1 mile north-west). Within a short drive, we also cover Winchester (13 miles north-west), Gosport (8 miles south), Havant (7 miles south-east), Eastleigh (10 miles west), Fareham (5 miles south-west) and Horndean (5 miles east).
Local landmarks in Newtown
Around Newtown, our work takes us to homes and buildings near The Bold Forester Public House. For rail, the closest station is Portchester station, about 4.4 miles south. Nearby you will also find Knowle Hospital (3.8 miles south-west). For a walk, there’s St Clair's Meadow and Portsdown Hill.
Landlords, agents and businesses in Newtown
Businesses can book us for washrooms, kitchens, offices and more. On commercial sites, working times can be discussed when we quote.
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.
Your questions about external mastic in Newtown
Can you help a landlord with a rental near Portchester station?
Yes, we work for landlords and letting agents. Just call 0345 464 0079 or send us an email and tell us about the property, and we’ll send you a clear quote.
Will you come out to Newtown?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
What information do you need?
The location, the problem and the rough size of the job. Photos by email help too.
Can you seal joints between render and window frames?
Yes. Different materials move at different rates, so a flexible sealant is needed where they meet. The sealant is matched to both sides.
What does external mastic cost?
It depends on the job, so we quote each one individually. To get one, call 0345 464 0079 or drop us an email with a short description of the job.
Can new sealant go over the old?
No. New silicone won’t bond to old silicone, and anything trapped underneath, including mould and water, stays there. It all has to come out first.
Are you ARBOMaster approved?
Yes. We’re approved under the ARBOMaster scheme, which is run for the Arbo sealant brand.
Can you match the colour of my brickwork?
Exterior sealants are made in a range of colours, from greys and browns to whites and stone shades. We choose the closest to your brick or render so it doesn’t stand out.
Towns and villages near Newtown
What else we do in Newtown
Aftercare tips
Looking after new joints is easy:
- Check external joints each spring
- Check the sealant is paintable before painting near it
- Show decorators and builders where the movement joints are
- Make sure movement joints are not pointed over
Don’t paint over the new sealant unless we’ve said the product is paintable. Many exterior sealants are not designed to be painted and spoil the finish.
Act while the splits are small. Then it’s a straightforward cut-out and reseal before water has had years to get in.
When to call us in Newtown
Sometimes a movement joint was filled with mortar or a rigid filler. With the joint locked solid, the movement turns into cracks elsewhere in the wall.
Most people get in touch when they notice one of these:
- Panel joints letting water in
- Sealant that has lost its bond to the brick or render
- Old sealant gone brittle and cracked
- Rain getting behind render or cladding at a joint
In the older streets around Church of the Holy Trinity, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
What your quote should include
- How hidden problems are handled
- Are they insured?
- Whether the sealant suits the joint
- How long to leave it before use
Different surfaces, different methods
Cladding and façade panels
Panel systems often rely on sealant between and around the panels. We reseal them with a sealant suited to the panel material.
Joints between dissimilar materials
Where a frame or panel meets masonry, water often finds a way in. We cut out the old sealant and reseal with a product suited to both surfaces.
Can I do it myself?
If you’ve already had a go yourself, that’s fine. We remove it and do the joint properly, so just mention it when you contact us.
What a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions.
What happens if it’s left?
A low-modulus sealant is chosen because it moves without pulling hard at the edges. That protects surfaces like brick, render and concrete. A stiffer product can damage the joint edge as it fails. Where a wall is exposed, as many are in small places like Newtown, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
Commercial jobs are quoted on the same basis as homes: the amount of work, the access and the products needed, along with when we can work on site. Call for a quick quote and we will explain what it covers.
Why us?
- You choose the colour before work begins
- An ARBOMaster approved applicator
- White, clear, grey or another colour, product permitting
- Colour picked to suit the job
Take a look at our cost guide and customer reviews.