Hampshire · England
Winnall External Mastic
External mastic for Winnall, by sealant specialists with 20+ years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Movement joints with cracked, split or missing sealant
- Failed sealant between panels on a façade
- Weeds or debris growing in open joints
How we handle external mastic in Winnall
Getting the depth right is half the job. Backing rod controls how deep the sealant goes and keeps it off the back of the joint, so it bonds to the two sides only and can stretch. We are often asked to deal with failed seals between different materials and sealant that has lost its bond to the brick or render, across joints between brick and frames, façade panels and concrete & block.
Houses in smaller places like Winnall can stand more in the open than those in a built-up town, so exposed walls and rooflines take more wind-driven rain. Joints on those sides are usually the first to go.
Each job carries a 12-month guarantee.
- Where
- Winnall (SO23, SO21, SO20)
- Wider area
- Hampshire
- Guarantee
- 12 months on all our work
- Quotes
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
When to call us in Winnall
UV, rain and frost all age exterior sealant. In time it goes hard, crazes on the surface and stops stretching, so the next time the wall moves, it splits or pulls away.
Any of these means the joints need attention:
- Movement joints with cracked, split or missing sealant
- Water getting into walls through failed joints
- Cracked joints where brick meets render or frames
- Movement joints filled with mortar instead of sealant
For landlords with property near Winchester station, split movement joints are easy to miss on a rental until damp shows inside.
Questions to ask before you book
- What happens if they find a problem under the old sealant
- Which colour the sealant will be
- How much experience the applicator has
- What guarantee comes with the work
Should I try it myself first?
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
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.
Aftercare tips
Joint life depends on how it’s used and looked after. We suggest:
- Do not let climbing plants root in the sealant
- Avoid pressure-washing directly into sealant joints
- Act on the first splits you see
- Tell anyone working on the walls about the movement joints
Keep the joints clear of soil, plants and climbing growth. Damp material against the sealant shortens its life.
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.
External mastic in Winnall: local notes
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.
In the older streets around Church of St John the Baptist, the joints between older walls, newer extensions and the roofline need a sealant that can move. Managing a site like Winnall Primary School? Then movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
Winnall is about 1 mile north-east of Winchester, in Hampshire. Winnall gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a 12-month guarantee. Winnall is one of 683 places in Hampshire where we work. Our Southampton page covers work nearby.
Every address in SO23, SO21 and SO20 is covered for external mastic, from the main roads to the quietest streets. That includes homes and businesses on Moss Road, Water Lane and Imber Road. Winnall is on the M3, which makes it straightforward to reach. Other places close to Winnall include Kings Worthy (2 miles north), Easton (2 miles north-east), Abbots Worthy (2 miles north), Temple Valley (2 miles east) and Morestead (3 miles south-east). Further out, we also cover Eastleigh (7 miles south), Fareham (15 miles south), Andover (13 miles north-west), Totton (14 miles south-west), Chandler's Ford (7 miles south-west) and Alton (15 miles north-east).
Near you in Winnall
We work in homes and buildings around Leigh House Hospital, The Golden Lion pub and St. Cross Park, among other places. The nearest railway station is Winchester station, about 1 mile west of the centre. Other landmarks nearby include Winchester City Museum (0.8 miles west) and Wolvesey Castle (0.7 miles south-west). For a walk, there’s Winnall Moors and Twyford Down.
How we quote for external mastic
The quote reflects the job in front of us. We look at:
- How much there is to do
- How easy the joints are to reach
- Any mould that needs treating
- Which sealant suits the joint
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.
Asking for a quote
You do not need to know the technical terms. Just tell us:
- What the problem is, such as mould, gaps, leaks or cracking
- How many joints, rooms or windows are involved
- Pictures of the joints, sent by email
- Any access issues, like height or stairs
To get a quote, call 0345 464 0079 or send us an email and tell us where the job is and what the problem looks like. We will give you a clear price before any work starts.
Places near Winnall
What else we do in Winnall
Leave it or put it right?
Mortar or ordinary filler might look like a quick way to close an open joint, but it stops the joint moving. The wall then cracks somewhere else. A flexible sealant over backing rod is what the joint needs. In an older home around Winnall, damp from a failed joint can get into timber and plaster, and that’s a much bigger job than renewing the sealant.
Doing several joints on one visit normally makes better use of the time than several visits. We’ll give you a clear quote for the lot.
Why Winnall customers choose us
- We leave the area clean and tidy
- We never seal over old sealant
- Arbo and Everbuild products
- Colour picked to suit the job
Questions from Winnall
I let a flat near Winchester station. Can you help?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. You can ring 0345 464 0079 or drop us an email with the details for a clear quote.
Do you cover smaller places like Winnall?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
What is backing rod for?
Backing rod goes into deeper joints as a matter of course. It sets the sealant depth and prevents three-sided bonding.
Do you take out the old sealant first?
Yes. Sealing over old sealant is the main reason resealing fails early, so we never do it.
Can I add another job to the visit?
Yes. Several rooms, windows or areas can go on one quote.
Can new sealant go over the old?
No, because it fails. We remove every bit of old sealant first.
How long does external mastic take?
As a guide, most jobs take a few hours for a handful of joints, longer for a whole elevation. Bigger jobs take longer, and we’ll tell you how long to expect.
Why is there a gap in my brick wall?
Brickwork, render and cladding all move a little, and planned joints take up that movement. It’s closed with backing rod and a flexible sealant.
How it works
You don’t need to clear the whole room or building before we come, only the area right around the joints. Everything nearby is protected, and the job takes a few hours to a few days, depending on the length of joint and the access for a typical job. A visit to Winnall is planned like any other: the time, the access and where to park are agreed in advance. Outdoor jobs depend on a dry day, since sealant needs a dry surface.
- First we look over the joints with you, agree which to renew and talk through access.
- Old sealant and any debris are cut and raked out.
- Both sides are cleaned back to sound material and primed if needed.
- Backing rod goes in next, setting the depth and keeping the sealant off the back of the joint.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Getting ready for the visit
- Let us know about earlier repairs to the joints
- Keep children and pets away from the work area
- Mention any sign-in or site rules at work premises
Getting a quote
A good description makes for an accurate quote. Tell us where the job is, what’s wrong and how much there is, and email pictures if that is easy.
Read more
What we cannot put right
To be straight with you, some problems need a different trade:
- Cracked brickwork or render that needs a builder or plasterer
- Rising or penetrating damp from elsewhere in the wall
- Cutting new joints into brickwork, which is building work rather than sealant work
Not sure which it is? You can ring 0345 464 0079 or send us an email and we will tell you honestly before you book.
Joints and surfaces we work on
- Brickwork movement joints
- Façade panels
- Concrete & block
- Render & cladding joints
- Copings & trims
- Joints between brick and frames