Hampshire · England
Marchwood External Mastic
External mastic across Marchwood and nearby, with old sealant always removed completely and a 12-month guarantee.
- Brick movement joints where the sealant has split
- Failed sealant between panels on a façade
- Cracked joints where brick meets render or frames
External mastic for homes and businesses in Marchwood
Many failed façade joints only get noticed once there’s a stain or a damp patch inside. We inspect them, agree which need doing and reseal with a weatherproof, flexible sealant. If you have movement joints with cracked, split or missing sealant and failed sealant between panels on a façade, we can help.
Outbuildings, garages and conservatories around homes in places like Marchwood add more joints to look after. Gutter ends, garage door frames and the joints where an extension meets the house are typical spots for leaks.
Whatever the size of the job, you get the same one-year guarantee.
- Place
- Marchwood (SO40)
- Region
- Hampshire
- Cover
- One year on every job
- Price
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
How to look after the new joints
Once the sealant has cured, a few habits help it last:
- Walk round the building once a year and look at the joints
- Avoid pressure-washing directly into sealant joints
- Leave the joints unpainted unless we have said otherwise
- Act on the first splits you see
Avoid pressure-washing straight into the joints. High-pressure water can lift the edges and let water in behind.
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 early resealing is worth it.
When something else is needed
New sealant cannot fix everything, and we will tell you before we start. It won’t solve:
- Failed render or damaged cladding panels
- Damp that is not coming from the joint
- Adding movement joints to masonry that has none
If you’re not sure, just ring 0345 464 0079 or send us an email and we will give you a straight answer.
What we seal
- Façade panels
- Joints between brick and frames
- Render & cladding joints
- Copings & trims
- Brickwork movement joints
- Concrete & block
What affects the cost of external mastic
We quote each job individually. These are the things that affect it:
- Working hours on commercial sites
- Access and height
- Whether old sealant or filler has to be cut out
- The size of the job
What it costs depends on the size of the job, how much old material has to come out and how easy the joints are to reach. We give a clear quote before we start.
Asking for a quote
Photos help, but a description is a good start. Try to tell us:
- The address or postcode of the job
- The problem you’ve noticed
- Roughly how big the job is
- Pictures of the joints, sent by email
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints.
DIY versus a professional finish
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.
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
Do you need external mastic in Marchwood?
Many joints fail because they were sealed too deep or with nothing behind them. If the sealant sticks to the back as well as the sides, it can’t stretch and tears as soon as the joint widens.
The most common problems we see are:
- Failed sealant between panels on a façade
- Plants rooting in failed movement joints
- Sealant that has lost its bond to the brick or render
- Hard, crazed mastic that has stopped moving
Rented homes near Millbrook (Hants) station change hands often, and split movement joints are easy to miss on a rental until damp shows inside.
Comparing quotes
- How the colour is chosen
- Who does the work, and how experienced they are
- What happens if they find a problem under the old sealant
- What the cure time is
The process
The work is kept neat and contained to the joints we’re treating. Expect the work to take a few hours to a few days, depending on the length of joint and the access. A visit to Marchwood is planned like any other: the time, the access and where to park are agreed in advance. If the work is outside, the weather plays a part, as sealant needs a dry surface.
- 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.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Preparing for the visit
- Keep children and pets away from the work area
- Clear items away from the joints we are working on
- Let us know about parking restrictions
Get a quote
Call for a quick quote, or send an email if you’d rather. Describe what needs sealing and we’ll explain what’s involved and give you a clear quote.
Read more
Landlord and commercial work in Marchwood
Hotels need rooms back in use, so the work can be planned room by room. We’ve worked in hotels as well as homes and businesses.
Housing providers, facilities teams and property managers book us too in Marchwood and across Hampshire. Several sites can go on one quote.
Outside joints around Marchwood
Marchwood is close to the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. That is hard on movement joints and outside wall joints, especially on the side facing the sea. London and the South East are among the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Managing a site like Marchwood Junior School? Then larger buildings have long runs of movement joint that eventually need resealing. In the older streets around Church of St John the Apostle, the joints between older walls, newer extensions and the roofline need a sealant that can move.
Marchwood is about 3 miles south-east of Totton, in Hampshire. Our applicators cover external mastic for householders, landlords and businesses in Marchwood and nearby, as part of our work across Hampshire. Our area takes in 683 places across Hampshire.
Jobs for external mastic in SO40 is quoted and booked the same way as anywhere else. External mastic is available to properties on Cranberry Close, Melick Close and The Rowans and the roads around them. Main roads around Marchwood include the A326, which makes travel easy. We also cover the places around Marchwood: Dibden (2 miles south-east), Dibden Purlieu (3 miles south-east), Hythe (3 miles south-east), Beaulieu (5 miles south) and Furzey Lodge (5 miles south). Further out, we also cover Winchester (13 miles north-east), Gosport (14 miles south-east), Eastleigh (7 miles north-east), Fareham (11 miles east), Totton (3 miles north-west) and Chandler's Ford (7 miles north-east).
Near you in Marchwood
We work in homes and buildings around White Horse pub and Hounsdown School, among other places. Marchwood’s nearest station is Millbrook (Hants) station, about 1.6 miles north-east of the centre. Well-known places in the area include Netley Castle (4.1 miles east) and Westquay (2.1 miles east). Green spaces nearby include Testwood Lakes.
Common questions in Marchwood
Does the coastal weather in Marchwood affect outside sealant?
Coastal homes put outside sealant through more weather than inland ones, so the choice of sealant and the preparation matter even more. Walls facing the sea are normally the first to need attention.
Do you cover smaller places like Marchwood?
Yes. Marchwood is within the area we cover, which takes in towns, villages and rural addresses. We work across London and the South East. Just mention lanes, gates or anything else about the route when you book.
Will the old sealant be removed?
Yes. All of the old material is cut out and the joint cleaned.
What sealant do you use?
We choose the sealant for the joint, not the other way round. Where it moves, gets wet or faces the weather makes a difference, and we will explain our choice.
Do the sealants smell?
It depends on the product. Some smell for a while, some hardly at all.
How often do external joints need resealing?
There’s no fixed answer: sunny, exposed elevations and busy joints wear faster. A yearly look will tell you when they need doing. Our work comes with a one-year guarantee.
Is it OK to fill a movement joint with cement?
No, not where the gap is a movement joint. Pointing it stops it working, and the wall may crack nearby. A flexible sealant is the right fill.
Do you have insurance?
Yes. Mr Mastic is fully insured, with over 20 years’ experience in sealant work.