Shetland Islands · Scotland
External Mastic in Walls
External mastic in Walls from a team with over 20 years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Movement joints with cracked, split or missing sealant
- Old sealant gone brittle and cracked
- Damp patches traced to an open external joint
External mastic in Walls, done properly
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. If you have rain getting behind render or cladding at a joint and movement joints with cracked, split or missing sealant, we can put it right, whatever the surface.
Older stone buildings need a sealant that suits the stone, not an acetoxy product that can mark or attack it. Newer houses need their movement joints and roofline trims kept sound.
There’s a 12-month guarantee on every job, large or small.
- Place
- Walls (ZE2)
- Region
- Shetland Islands
- Cover
- 12 months on all our work
- Quotes
- Quoted before any work starts
- info@mrmastic.co.uk
- Page updated
- 26 October 2026
Your questions about external mastic in Walls
Do you cover Walls for external mastic?
Yes, Walls is within the area we cover. Our work covers the whole of Scotland. You can drop us a line at info@mrmastic.co.uk and let us know what needs doing.
Is external mastic in a coastal place like Walls any different?
Near the sea, outside joints face more wind, rain and salt than they would inland, so preparation and the right sealant matter all the more. It’s worth checking the walls that face the sea first.
How do you reach high-level joints?
It depends on the building. We work on joints that can be reached safely. Tell us about the building and we will confirm what access is needed.
What colours does the sealant come in?
The aim is a neat, even joint in a colour that suits the wall. We’ll talk through colour options before we start, matched as closely as the range allows.
Does someone need to be in?
That depends on where the joints are. For work indoors, someone needs to let us in, while outside work can sometimes be arranged differently.
Do you work for letting agents?
Yes, we do. Domestic, commercial and hotel work are all part of what we do.
Should I point up the gap in my brickwork?
No, not if it’s a movement joint. Pointing it stops it working, and the wall may crack nearby. A flexible sealant is the right fill.
Can you work on commercial sites?
Yes, regularly. Larger jobs can be planned room by room or area by area to suit the site.
When to call us in Walls
Sometimes a movement joint was filled with mortar or a rigid filler by mistake. The joint can’t move, so the wall cracks somewhere else instead.
Look out for any of the following:
- Failed seals between different materials
- Joints with sealant missing in places
- Damp patches traced to an open external joint
- Movement joints filled with mortar instead of sealant
Whether the job is in Walls itself or nearby, the right material for each joint matters as much as a neat finish.
What to look for in a quote
- The length of the guarantee
- What happens if they find a problem under the old sealant
- How the joint is cleaned and prepared
- Is the old sealant removed completely?
What else we do in Walls
Landlord and commercial work in Walls
In hotels, rooms out of use cost money, so we plan the work room by room. Hotel work is part of what we do, alongside homes and businesses.
We work for landlords and agents as well as homeowners. Sealant work between tenants is a simple way to keep a property in good order before the next move-in.
When something else is needed
It helps to know what we can’t do too:
- Cracks in the bricks or render themselves, away from the joints
- Loose or hollow render, which needs re-rendering
- Adding movement joints to masonry that has none
If you are not sure, just email us at info@mrmastic.co.uk and we’ll give you a straight answer.
Joints and surfaces we work on
- Concrete & block
- Façade panels
- Render & cladding joints
- Brickwork movement joints
- Joints between brick and frames
- Copings & trims
How the job changes by surface
Cladding and façade panels
Panels heat up and cool down quickly, so the joints work hard every day. We choose the product to suit.
Brickwork movement joints
Brick movement joints are often mistaken for a missing mortar line. Where one has been mortared, we cut it out and reseal it with sealant.
What external mastic looks like in Walls
Walls is within about 1 mile of the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. Both are hard on movement joints and outside wall joints, which can dry out and crack sooner where a building faces the weather. Island jobs need planning around ferries and the weather, so give us as much notice as you can.
In and around Walls, as anywhere, good external mastic starts with a clean, dry, properly prepared joint.
Walls is in the Shetland Islands. If you need external mastic in Walls, please send an email to info@mrmastic.co.uk for a quick quote. We cover the Shetland Islands from our Crawley base. 63 places in the Shetland Islands are on our list, from the larger towns to small villages.
Jobs for external mastic in ZE2 is quoted and booked the same way as anywhere else. That includes homes and businesses on New Road, Vagaland and Pier Road. Other places close to Walls include Easter Skeld (5 miles south-east), Sandness (6 miles north-west), Melby (6 miles north-west), Aith (8 miles north-east) and Kalliness (9 miles east). We also work in nearby towns such as Lerwick (15 miles east), Sound (15 miles south-east), Scalloway (12 miles south-east) and Brae (14 miles north-east). Remote and island addresses need a little more planning, so please mention your location when you send an email to info@mrmastic.co.uk.
Around Walls
Green spaces nearby include Loch of Bardister and Ward of Culswick.
Why deal with it now?
It often makes sense to reseal all the failing joints on an elevation together. They’ve weathered the same way, and access only has to be arranged once. Exposed walls in smaller Scottish places take a lot of wind and rain, and once water gets behind a failed joint, damp in stone or harled walls is slow to dry out.
Doing several joints on one visit is normally more efficient than separate visits, so tell us about everything that needs sealing. We will send you a clear quote for the lot.
Why choose Mr Mastic in Walls
- Trusted Arbo and Everbuild sealants
- Any old sealant cut out fully, not covered over
- Sealant colour chosen to suit
- Colour agreed with you before we start
Take a look at our cost guide and what customers say.
The process
Every visit runs the same way: we check the joints, protect the area around them, do the work and clear up. Most jobs take anything from a few hours to several days, depending on the building. Outside jobs in Walls need a dry day, because sealant will not bond to a wet joint, so external jobs may need to move if the day turns wet. Work indoors isn’t affected.
- We start by checking each joint, agreeing the ones to redo and how we will reach them.
- The old mastic and anything lodged in the joint is removed.
- The joint faces are cleaned and primed where the sealant needs it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
How to prepare
- For indoor joints, keep the area dry beforehand if you can
- Mention any leaks or damp you’ve noticed
- Tell us if parking is tricky
Get a quote
For a quote, email us at info@mrmastic.co.uk and tell us where the job is and what the problem looks like. We’ll give you a clear price before any work starts.
Read more
Quotes for external mastic in Walls
Your quote is based on your job. We look at:
- The old material and how stubborn it is
- The type of sealant required
- How many areas need sealing
- Whether there’s mould to deal with
Instead of a standard rate, we price the job in front of us: the amount of work, the old material and the access. You will know the price before we begin.
What to tell us for a quote
Photos by email are helpful but not essential. Try to tell us:
- The address or postcode of the job
- How many joints, rooms or windows are involved
- Any previous sealing or DIY work
- Pictures of the joints, sent by email
We quote each job on its own. Just email us at info@mrmastic.co.uk with the details and send photos if you have them.