Hampshire · England
External Mastic in Chilbolton
We cover Chilbolton for sealing brickwork movement joints, render, cladding and façade joints. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Movement joints filled with mortar instead of sealant
- Weathered mastic that no longer stretches
- Sealant pulling away from one side of the joint
DIY sealant or a professional job?
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it peels away and traps moisture behind it. All the old material has to come out first.
About our external mastic in Chilbolton
Low-level joints can generally be done from the ground. Where joints are higher up, tell us about the building when you get in touch and we’ll confirm what access is needed. If you have brick movement joints where the sealant has split and plants rooting in failed movement joints, we can help, on brickwork movement joints, joints between brick and frames and façade panels alike.
Outside joints can only be sealed when they’re dry, so work in Chilbolton is booked around the forecast. Tell us about access to all sides of the building, including outbuildings and garages.
Big or small, it’s backed by our 12-month guarantee.
- Where
- Chilbolton (SO20)
- Region
- Hampshire
- Cover
- 12 months on all our work
- Quote
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Questions from Chilbolton
Do you work for landlords with property near Andover station?
Yes, we work for landlords and agents. You can phone 0345 464 0079 or drop us an email with the address and a few details, and we will give you a fixed price before work begins.
Is Chilbolton within the area you cover?
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.
Do you take out the old sealant first?
Yes. Sealing over the old bead is the commonest cause of early failure, and it’s something we never do.
Can you seal joints between two different materials?
Yes. Different materials move at different rates, so the joint between them must be flexible. The sealant is matched to both sides.
Will the new joint stand out?
We aim for a joint that suits the wall rather than one that jumps out. We will talk through colour options before we start from the range available.
How do I get a quote for external mastic in Chilbolton?
Size, access and the old material all affect the cost. Ask us for a quote.
Do you do commercial work?
Yes. We’ve worked for hotels, offices and other businesses and we are fully insured.
Why is there a gap in my brick wall?
A vertical gap in a long brick wall is usually a movement joint. It gives the wall room to move, and it should be sealed with a flexible sealant.
Outside joints around Chilbolton
The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Managing a site like Wherwell Primary School? Then its movement joints, gutters and trims need looking after like any other building’s. If you live in an older home near Church of St Mary the Less, older walls, gutters and the joints where extensions meet them need a flexible sealant.
Chilbolton is about 4 miles south-east of Andover, in Hampshire. From the centre of Chilbolton to the outskirts, we cover external mastic for every kind of property. 683 places in Hampshire are on our list. You can also see our page for Southampton, roughly 16 miles from Chilbolton.
Here we cover the SO20 postcode area for external mastic. External mastic is available to properties on Station Road, Test Rise and Drove Hill. Nearby, we also carry out external mastic in Cottonworth (1 mile west), Wherwell (1 mile north), Fullerton (1 mile west), Leckford (2 miles south-west) and Wherwell Wood (2 miles north-west). Further out, we also cover Winchester (8 miles south-east), Eastleigh (13 miles south), Andover (4 miles north-west), Chandler's Ford (12 miles south), Romsey (11 miles south) and Hyde (8 miles south-east).
Local landmarks in Chilbolton
In Chilbolton, that means homes and buildings near Longstock Park and Abbots Mitre pub. The closest station to Chilbolton is Andover station, roughly 4.7 miles north-west. Nearby you will also find Andover War Memorial Hospital (5 miles north-west). For a walk, there’s Mill Lake.
What happens on the day
Once we are on site, we compare the joints with what we discussed. If we find something unexpected, we talk it through with you first. After that, the work takes anything from a few hours to several days, depending on the building. Somewhere as small as Chilbolton, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- 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.
- The faces are brushed clean and primed where the product requires it.
- Backing rod sized to the joint goes in to set the depth.
- We apply the sealant, tool it and check the whole run.
Before we arrive
- Tell us if parking is tricky
- For business premises, tell us about site rules or sign-in
- For indoor joints, keep the area dry beforehand if you can
Ask for a quote
We quote each job on its own, so start by telling us what you need. Simply call 0345 464 0079 or send us an email and describe the job and send photos if you have them.
Advice
What we can’t put right
New sealant cannot fix everything, and we’d rather say so up front. It won’t solve:
- Rising or penetrating damp from elsewhere in the wall
- Cutting new joints into brickwork, which is building work rather than sealant work
- Movement that is more than a sealant joint can take
Not sure which it is? You can call 0345 464 0079 or drop us an email and we will tell you honestly.
Where we work in Chilbolton
- Copings & trims
- Render & cladding joints
- Concrete & block
- Façade panels
- Joints between brick and frames
- Brickwork movement joints
How to look after the new joints
No joint lasts for ever, but care makes a real difference. Our tips:
- Tell anyone working on the walls about the movement joints
- Have failed joints looked at early
- Look over the joints every year, ideally after winter
- Fix overflowing gutters above sealed joints
Keep pressure washers away from the sealant. High-pressure water can lift the edges.
Once a joint cannot move, the wall finds another way, usually as cracking in the brickwork or render nearby. Resealing it early helps prevent that.
What we’re called out for in Chilbolton
The wrong product in a moving joint is a classic cause. A stiff, general-purpose sealant can’t cope with a joint that moves a lot, so it pulls away from the edges.
Common reasons people contact us are:
- Movement joints with cracked, split or missing sealant
- Failed seals between different materials
- Rain getting behind render or cladding at a joint
- Old sealant gone brittle and cracked
If you let a flat or house near Andover station, split movement joints are easy to miss on a rental until damp shows inside.
Questions to ask before you book
- Is VAT in the price?
- Is the old sealant removed completely?
- Are they insured?
- How the joint is cleaned and prepared
Surface by surface
Brickwork movement joints
Vertical joints in long brick walls let the brickwork expand without cracking. We reseal them with a low-modulus sealant over backing rod coloured to suit the wall.
Render joints
Render is weaker at the surface than brick, so a sealant that stretches easily protects the edges. We prime where the product needs it.
Why act early in Chilbolton
Mortar or ordinary filler might look like a quick way to close an open joint, but it stops the joint moving. The movement then cracks the brickwork or render nearby. A flexible sealant over backing rod is what the joint needs. Around Chilbolton, older homes often have timber in their floors and frames, and water through a failed joint can rot timber if it’s left.
We don’t show prices on the website, because each job is priced on what it involves. Call for a quick quote.
Why choose Mr Mastic in Chilbolton
- A choice of colours where the product allows
- Neat joints and a tidy finish
- Domestic, commercial and hotel work
- Approved under the ARBOMaster scheme