Hampshire · England
External & façade joints in Test Valley, Hampshire
Our applicators work in Test Valley on sealing brickwork movement joints, render, cladding and façade joints. Old material cut out, joints cleaned and sealed neatly and a 12-month guarantee.
- Moss and dirt in joints with no sealant left
- Gaps where render, brick and frames meet
- Rain getting behind render or cladding at a joint
External mastic in Test Valley, done properly
Getting the depth right is half the job. Closed-cell backing rod sets the depth and stops the sealant sticking to the back, so it bonds to the two sides only and can stretch. If you’re dealing with joints with sealant missing in places and moss and dirt in joints with no sealant left, we can put it right.
Somewhere as small as Test Valley, 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.
You’re covered for a year from the day we finish. If anything is not right with it, ring 0345 464 0079 or email us.
- Place
- Test Valley (SP11)
- Region
- Hampshire
- Cover
- One year on every job
- Quote
- A clear price before work begins
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
The process
You do not need to clear the whole room or building, only the area right around the joints. Everything nearby is protected, and the job takes a few hours for a handful of joints, longer for a whole elevation in most cases. For a village or hamlet like Test Valley, the journey is planned in advance: let us know about lanes, gates and parking. We bring what the job needs, so it can be finished in one trip where possible.
- We start by walking round the building and agreeing the joints and the access.
- Every bit of old sealant and any mortar or debris is cut out.
- 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.
Preparing for the visit
- Tell us about access, such as stairs, a lift or high-level joints
- Tell us if parking is tricky
- Tell us about any water getting in
Getting a quote
Call for a quick quote, or send an email if you’d rather. Tell us about the joints that need doing and we’ll talk you through the work and give you a clear quote.
Related advice
Nearby places to Test Valley
What else we do in Test Valley
Do you need external mastic in Test Valley?
The wrong product in a moving joint is a classic cause. A high-modulus or general-purpose sealant can be too rigid for a busy joint, so it pulls away from the edges.
Any of these means the joints need attention:
- Failed sealant between panels on a façade
- Movement joints with cracked, split or missing sealant
- Damp patches traced to an open external joint
- Sealant that has lost its bond to the brick or render
In the older streets around Church of St James, older walls, gutters and the joints where extensions meet them need a flexible sealant.
What your quote should include
- How long the guarantee is
- How the joint is cleaned and prepared
- What product goes in the joint
- Whether you can choose the colour
Test Valley buildings and the weather
With historic houses such as Stargroves (about 2.7 miles north) nearby, there’s older building stock in the area around Test Valley as well as newer homes. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth. 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.
In and around Test Valley, as anywhere, good external mastic starts with a clean, dry, properly prepared joint.
Test Valley is about 7 miles north of Andover, in Hampshire. Every kind of property in Test Valley can book us for external mastic, old or new, large or small. Every job comes with our one-year guarantee. Our Hampshire coverage runs to 683 places, Test Valley among them. Reading is on our list too, around 22 miles away.
Jobs for external mastic in SP11 works the same way as everywhere else we cover. If you’re just outside Test Valley, we cover Ashmansworth (1 mile east), Vernham Street (3 miles west), Upper Green (4 miles north), Inkpen Common (5 miles north) and Hell Corner (5 miles north). Further out, we also cover Basingstoke (15 miles east), Andover (7 miles south), Tadley (13 miles east), Popley (15 miles east), Tidworth (11 miles south-west) and Kempshott (13 miles east).
Landmarks near Test Valley
Not far away are Pilot Hill.
Common questions in Test Valley
Is Test Valley within the area you cover?
Yes, we do. Our work covers London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
What guarantee comes with external mastic in Test Valley?
Every job comes with our one-year guarantee, wherever it is. We are fully insured, and an ARBOMaster approved applicator.
How long does the job take?
It depends on the size of the job, but as a guide it takes a few hours for a handful of joints, longer for a whole elevation. We’ll give you a better idea when we quote.
Should I try DIY first?
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.
Where are you based?
Our base is in Crawley, West Sussex, and we work across South East England, London and Scotland.
When will the joints need doing again?
That varies with the weather the wall faces, how much it moves and the sealant used. Sealant is a maintenance item, so check the joints once a year and reseal when it splits.
What do you need from me for a quote?
Where the job is, what the problem is and roughly how big it is. If you can, email a few photos.
Are you ARBOMaster approved?
Yes. We are ARBOMaster approved, the scheme for applicators of Arbo sealants.
Aftercare tips
Good habits help new joints last longer. A few tips:
- Keep soil, plants and ivy away from the joints
- Walk round the building once a year and look at the joints
- Keep movement joints as flexible joints, not mortar
- Deal with leaking gutters that soak the joints below
Don’t let soil, plants or ivy build up against the new joints. 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.
DIY versus a professional finish
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.
Sealing over old silicone is the commonest DIY error. New silicone won’t bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
What happens if it’s left?
Resealing a run of joints in one go is normally better than patching one at a time. Joints of the same age tend to fail together, and access only has to be arranged once. Around Test Valley, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
There are no prices on our website, because the cost depends so much on the job itself. Call for a quick quote.
Why us?
- White, clear, grey or another colour, product permitting
- 180+ five-star Google reviews
- An ARBOMaster approved applicator
- Neat joints and a tidy finish
See our cost guide or our reviews.
Quotes for external mastic in Test Valley
Call for a quick quote. What matters most is:
- Access and height
- Which sealant suits the joint
- The number of rooms or windows
- Any mould that needs treating
Combining jobs into one visit is generally more efficient than separate visits, so tell us about everything that needs sealing. We’ll give you a clear quote for the lot.
What we need to know
Photos by email are helpful but not essential. Please mention:
- Access, such as stairs, a lift or height
- The type of property
- Any previous sealing or DIY work
- Roughly how big the job is
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints, and add pictures by email if you can.
Different surfaces, different methods
Brickwork movement joints
Brick walls have vertical movement joints to absorb expansion. We reseal them with a low-modulus sealant over backing rod coloured to suit the wall.
Concrete and blockwork
Big joints in concrete need careful depth control. We size the backing rod to the gap so the sealant isn’t too deep.