West Sussex · England
External Mastic in Walberton
Professional external mastic in and around Walberton, with old sealant always removed completely.
- Plants rooting in failed movement joints
- Brick movement joints where the sealant has split
- Movement joints filled with mortar instead of sealant
Your questions about external mastic in Walberton
I let a flat near Barnham station. Can you help?
Yes, rental work is part of what we do. You can ring 0345 464 0079 or drop us an email with the address and a few details, and we’ll give you a fixed price before we start.
Will you come out to Walberton?
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.
Where is Mr Mastic based?
Our base is Crawley. Our area covers South East England, London and Scotland.
Do you do commercial work?
Yes. Commercial and hotel work is a large part of what we do, as well as homes. Working times can be discussed when we quote.
Should I point up the gap in my brickwork?
No. Rigid materials can’t move with the wall and the joint fails. If it has already been filled, we can generally cut it out and reseal it.
What is backing rod for?
We fit closed-cell backing rod wherever the joint depth needs controlling. It sets the sealant depth and prevents three-sided bonding.
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. We’ll confirm how long when we quote.
What do you need from me for a quote?
A short description and the location, plus photos if you have them. We will ask anything else we need to know.
External mastic in Walberton
Short cuts in external joints show up within a season or two. Overfilled joints, missing backing rod and sealant laid over old sealant all tend to fail early. We strip the joint back and start again. Typical jobs include brick movement joints where the sealant has split and panel joints letting water in, across render & cladding joints, joints between brick and frames and copings & trims.
Outside joints can only be sealed when they’re dry, so work in Walberton is booked around the forecast. Let us know about access to every wall, plus any garages or outbuildings.
We guarantee the work for a year. If something is not right with it in that time, tell us and we’ll put it right.
- Where
- Walberton (BN18)
- Wider area
- West Sussex
- Cover
- One year on every job
- Quotes
- A clear price before work begins
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
When something else is needed
A few problems are outside what sealant work can do:
- Movement that’s more than a sealant joint can take
- Render that is blown, hollow or coming away
- Cracked brickwork or render that needs a builder or plasterer
If in doubt, ring 0345 464 0079 or send us an email and we will say what we think before you book.
What we seal
- Façade panels
- Concrete & block
- Copings & trims
- Render & cladding joints
- Brickwork movement joints
- Joints between brick and frames
DIY sealant or a professional job?
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.
If you’ve already had a go yourself, that’s fine. We cut it out and start again.
How to look after the new joints
Aftercare is simple:
- Fix overflowing gutters above sealed joints
- Have failed joints looked at early
- Avoid pressure-washing directly into sealant joints
- Show decorators and builders where the movement joints are
Only paint over the joint if we have confirmed the sealant can take paint. Many exterior sealants are not designed to be painted, and paint can crack as the joint moves.
Act while the splits are small. At that stage it’s a simple cut out and reseal.
Signs you need external mastic in Walberton
Sometimes a movement joint was filled with mortar or a rigid filler, often by someone who didn’t know what it was for. With the joint locked solid, the movement turns into cracks elsewhere in the wall.
Most people get in touch when they notice one of these:
- Old sealant gone brittle and cracked
- Gaps where render, brick and frames meet
- Sealant pulling away from one side of the joint
- Movement joints filled with mortar instead of sealant
If you live in an older home near St Mary's Church, an extension built onto an older house moves differently, and the joint between them takes the strain.
Questions to ask before booking
- The length of the guarantee
- What happens if they find a problem under the old sealant
- What the quote includes, VAT included or not
- Which colour the sealant will be
Landlord and commercial work in Walberton
From a single let to a portfolio, the work is the same standard: the old material taken out, careful preparation and a 12-month guarantee.
Mouldy or split sealant often shows up at the end of a tenancy, and it’s easy to sort out between tenants. We can quote for more than one property at once.
How it works
When we arrive, we start by going over the job with you, so there are no surprises. We protect the surfaces around the joints before work begins. Most jobs take anything from a few hours to several days, depending on the building. Somewhere like Walberton needs a little journey planning: tell us about narrow lanes, gates, long drives and where we can park. We bring what the job needs, so it can be finished in one trip where possible.
- 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.
- We clean both faces of the joint and prime them where the product calls for it.
- We push in closed-cell backing rod so the sealant is the right depth and bonds to the sides only.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Preparing for the visit
- Mention any leaks or damp you’ve noticed
- On commercial sites, let us know about site rules
- Clear the area around the work
Getting a quote
For external mastic in Walberton, phone 0345 464 0079 or send us an email. A short description of the job and where it is helps us quote, and we will agree the price before any work begins.
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Places near Walberton
Also in Walberton
Why deal with it now?
Water gets in through a failed movement joint, behind render and cladding. Dealing with it early keeps the repair to the joint, rather than the wall around it. In a small place like Walberton, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
What it costs depends on how much there is to do, how much old material has to come out and access to the work. We give a clear quote before work begins.
Why book with us
- Colour agreed with you before any work starts
- Domestic, commercial and hotel work
- 4.9 on Google from 180+ five-star reviews
- Full insurance on every job
Take a look at what affects the cost or our reviews.
Walls and rooflines in Walberton
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 Barnham station, split movement joints are easy to miss on a rental until damp shows inside. Managing a site like Walberton and Binsted CofE Primary School? Then larger buildings have long runs of movement joint that eventually need resealing.
Walberton is about 5 miles north-west of Littlehampton, in West Sussex. Wherever you are in the BN18 postcode area, our applicators can take on external mastic. Walberton is one of 371 places in West Sussex we cover for external mastic. There’s also a page for Portsmouth, roughly 20 miles from Walberton.
Every address in BN18 is covered for external mastic. You will find streets such as The Street, Maple Road and Prime Close. Neighbouring places we cover for external mastic include Avisford (1 mile north-east), Binsted (1 mile east), Slindon Common (1 mile north), West Barnham (1 mile south-west) and Barnham (1 mile south-west). Further out, we also cover Worthing (10 miles east), Bognor Regis (5 miles south-west), Chichester (7 miles west), Selsey (11 miles south-west), Littlehampton (5 miles south-east) and Shoreham-by-Sea (15 miles east).
Near you in Walberton
We work in homes and buildings around St Philip Howard Catholic High School, among other places. For rail, the closest station is Barnham station, about 1.3 miles south-west. Other landmarks nearby include Arundel and District Hospital (2.5 miles east) and Arundel Castle (3 miles east). Green spaces nearby include WWT Arundel and Bignor Hill.