Hampshire · England
External Mastic in Michelmersh
Sealing brickwork movement joints, render, cladding and façade joints for householders, landlords and businesses in Michelmersh. Fully insured, ARBOMaster approved and guaranteed for a year.
- Brick movement joints where the sealant has split
- Panel joints letting water in
- Failed seals between different materials
Leave it or put it right?
An open joint keeps letting water into the wall with every downpour. In cold weather, frost can damage wet brick and render, so the damage spreads beyond the joint. Where a wall is exposed, as many are in small places like Michelmersh, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
What you pay reflects the work, not a rough estimate. That’s why we ask about the job first and agree the price before starting.
Why choose Mr Mastic in Michelmersh
- 20+ years of sealant experience
- White, clear, grey or coloured to suit, where the product allows
- 12-month guarantee on every job
- Tidy, careful work
External mastic for homes and businesses in Michelmersh
Low-level joints can usually be done from the ground. Where joints are higher up, tell us about the building when you get in touch and we will confirm what’s needed to reach them safely. We work on render & cladding joints, façade panels and joints between brick and frames, and people most often call us about brick movement joints where the sealant has split and weathered mastic that no longer stretches.
Around Michelmersh, older buildings can be stone, brick or timber-framed, many with extensions added later. Where one material meets another is where water usually gets in.
A one-year guarantee comes as standard, so you’re not left on your own once the job is done.
- Where
- Michelmersh (SO51)
- Wider area
- Hampshire
- Guarantee
- 12 months on all our work
- Quotes
- Quoted before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Nearby places to Michelmersh
Also in Michelmersh
How to look after the new joints
A little care helps the new joints last. Our advice:
- Tell anyone working on the walls about the movement joints
- Keep high-pressure jets off the joints
- Look over the joints every year, ideally after winter
- Keep water from gutters off the wall
Have a quick look at the joints each spring. Splits, gaps at the edges or plants in the joint are early warning signs.
Gaps, plants or missing sealant in a joint are worth getting looked at. Early work is quicker and leaves a better finish.
The process
On the day, we start by going over the job with you, so you know exactly what we’re doing. We protect the surfaces around the joints before any work starts. The work generally takes a few hours to a few days, depending on the length of joint and the access. For a village or hamlet like Michelmersh, the journey is planned in advance: let us know about lanes, gates and parking. Everything for the job comes with us, so a second trip is avoided where possible.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- Joint faces are cleaned back and primed if the sealant needs it.
- Backing rod sized to the joint goes in to set the depth.
- The exterior sealant is applied, tooled and checked along its length.
Before we arrive
- For business premises, tell us about site rules or sign-in
- Let us know if you’ve seen damp or leaks
- Where the joints are inside, avoid wetting them before we arrive
Ask for 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 will explain what’s involved and send you a clear quote.
Related advice
What the job involves on each surface
Joints between dissimilar materials
Different materials may need different primers. We prepare both faces so the sealant bonds properly.
Brickwork movement joints
Clay brickwork grows slightly over its life and moves with the weather. The movement joint takes that up, so its sealant has to stay flexible.
External mastic in Michelmersh: local notes
Historic houses like Mottisfont Abbey (about 1.2 miles north-west) are a reminder that the area around Michelmersh has older buildings as well as new. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
If you let a flat or house near Mottisfont & Dunbridge station, outside joints that have cracked can let damp into a rental, so check them between lets.
Michelmersh is about 3 miles north-west of Romsey, in Hampshire. From the centre of Michelmersh to the outskirts, external mastic is available for homes and businesses alike. We cover 683 towns and villages across Hampshire. There’s also a page for Southampton, about 9 miles away.
We work across SO51 for external mastic. If you need external mastic at a property on Yew Tree Lane, Staff Road and Haccups Lane or anywhere close by, we can help. If you are just outside Michelmersh, we cover Timsbury (1 mile south), Stonymarsh (1 mile north-west), Kimbridge (1 mile west), Mottisfont (1 mile west) and Dunbridge (1 mile west). Larger places within reach include Winchester (9 miles east), Eastleigh (9 miles south-east), Andover (12 miles north), Totton (8 miles south), Chandler's Ford (6 miles south-east) and Hedge End (12 miles south-east).
Local landmarks in Michelmersh
In Michelmersh, that means homes and buildings near The Malthouse Inn and the streets around them. The closest station to Michelmersh is Mottisfont & Dunbridge station, roughly 1.5 miles west of the centre. Well-known places in the area include King Johns House (3 miles south) and Romsey Community Hospital (3.1 miles south-east). Green spaces nearby include Emer Bog and Baddesley Common.
FAQs for Michelmersh
Is Michelmersh in your area for external mastic?
Yes. We work across London and the South East, and Michelmersh is part of that. Just call 0345 464 0079 or email us with a few details of the job, and we will give you a clear quote.
I let a flat near Mottisfont & Dunbridge station. Can you help?
Yes, landlords and agents are among the people we work for. You can call 0345 464 0079 or email us with the details for a clear quote.
Can you seal joints between render and window frames?
Yes. Different materials move at different rates, so the joint between them must be flexible. We choose one that suits both surfaces.
How long does external mastic take?
A typical job takes anything from a few hours to several days, depending on the building, including preparation and clearing up. Your quote will say how long we expect yours to take.
Can you do several jobs on one visit?
Yes. Tell us about everything you’d like done and we will quote it together.
When is the sealant fully cured?
Different products cure at different speeds, so follow the cure time we give you when we finish.
Do you take out the old sealant first?
Yes, always, and completely. New silicone does not stick to old silicone, so the joint is cleaned back first.
Can you match the colour of my brickwork?
The sealant colour is picked to suit the wall, so the joint sits quietly in the wall. There’s a wide choice of exterior colours.
Common problems we fix in Michelmersh
Joints sealed without backing rod, or far too deep, rarely last. If the sealant sticks to the back as well as the sides, it cannot stretch and tears as soon as the joint widens.
Keep an eye out for any of the following:
- Sealant pulling away from one side of the joint
- Old sealant gone brittle and cracked
- Panel joints letting water in
- Cracked joints where brick meets render or frames
For an older house near a landmark such as Church of St Mary, older walls, gutters and the joints where extensions meet them need a flexible sealant.
Comparing quotes
- Whether they seal over old material or remove it
- What the cure time is
- Are they insured?
- How hidden problems are handled
Honest limits
Some problems need a builder, plumber or other trade rather than us:
- Walls that need new movement joints cut into them
- Rising or penetrating damp from elsewhere in the wall
- Cracking across the wall rather than at a joint
Not sure which it is? You can ring 0345 464 0079 or email us and we will tell you honestly before you book.
Joints and surfaces we work on
- Concrete & block
- Façade panels
- Copings & trims
- Joints between brick and frames
- Render & cladding joints
- Brickwork movement joints
DIY sealant or a professional job?
Some sealant jobs are within reach of a careful DIYer, 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.
A DIY attempt does not rule out a professional job. We remove it and do the joint properly.