South Lanarkshire · Scotland
External Mastic in Thankerton
Professional external mastic in and around Thankerton, with old sealant always removed completely and a 12-month guarantee.
- Moss and dirt in joints with no sealant left
- Failed sealant between panels on a façade
- Rain getting behind render or cladding at a joint
When it is not the sealant
In fairness, there are a few things sealant will not fix:
- Cutting new joints into brickwork, which is building work rather than sealant work
- Subsidence or other structural problems
- Failed render or damaged cladding panels
If you’re not sure, just email us at info@mrmastic.co.uk and we will give you a straight answer before booking.
Where we work in Thankerton
- Render & cladding joints
- Joints between brick and frames
- Copings & trims
- Façade panels
- Brickwork movement joints
- Concrete & block
How we handle external mastic in Thankerton
Short cuts in external joints show up within a season or two. New sealant over old, joints packed with mortar and beads with no backing rarely last long. We strip the joint back and start again. We work on concrete & block, joints between brick and frames and brickwork movement joints, and people most often call us about plants rooting in failed movement joints and movement joints with cracked, split or missing sealant.
Stone walls need a stone-friendly sealant, as acetoxy products can attack some stone. Newer houses need their movement joints and roofline trims kept sound.
Whatever the size of the job, it’s backed by our 12-month guarantee.
- Place
- Thankerton (ML12)
- Wider area
- South Lanarkshire
- Guarantee
- One year on every job
- Quotes
- Quoted before any work starts
- info@mrmastic.co.uk
- Page updated
- 26 October 2026
Common problems we fix in Thankerton
Using the wrong sealant is another common reason. A high-modulus or general-purpose sealant can be too rigid for a busy joint, so it pulls away from the edges.
People generally contact us when they notice one of these:
- Damp patches traced to an open external joint
- Hard, crazed mastic that has stopped moving
- Rigid filler in a joint that should flex
- Cracked joints where brick meets render or frames
In the older streets around Covington Parish Church, an extension built onto an older house moves differently, and the joint between them takes the strain.
Before booking anyone
- What the cure time is
- How long the guarantee is
- How much experience the applicator has
- How the surfaces are prepared before sealing
Common questions in Thankerton
Do you cover smaller places like Thankerton?
Yes, we do. We work across all of Scotland, and smaller places are part of that. The journey is planned ahead, so it helps to know about access.
Can you help a landlord with a rental near Carstairs station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. Just send an email to info@mrmastic.co.uk with the address and what needs doing, and we’ll send you a clear quote.
What is a movement joint?
Most straight vertical gaps in brickwork are movement joints. It gives the wall room to move and needs a flexible seal, not mortar.
Are you insured?
Yes. We’re fully insured.
Can I add another job to the visit?
Yes, and it often makes sense. Combining jobs makes good use of the visit.
Can you reach joints on upper floors?
It depends on the building. We work on joints that can be reached safely. Give us some details and we’ll confirm the access.
Can new sealant go over the old?
No, and we never do. It may look fine at first, but the new layer lifts away from the old one. Removing the old sealant completely is the only lasting way.
Can a movement joint be filled with mortar?
No. Rigid materials cannot move with the wall, so the joint stops doing its job. If it has already been filled, we can usually cut it out and reseal it.
Should I try it myself first?
If you’ve already had a go yourself, that is fine. We cut it out and start again, so just mention it when you contact us.
What a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is chosen for how the joint moves and where it is, and the work is guaranteed for a year.
What affects the cost of external mastic
The quote reflects the job in front of us. We take into account:
- How many areas need sealing
- When we can work, for business premises
- How much old sealant there is and how hard it is to remove
- Access and height
Some things make a job bigger or smaller: how much old sealant there is and how stubborn it is, any mould to treat, and whether the work is at height. Your quote takes all of that into account.
What we need to know
When you call or email, it’s useful to know:
- Whether it has been sealed before
- Where the job is, and your postcode
- Photos by email, if that is easy
- How we’d reach the joints
Getting a quote is simple: let us know what needs doing and where. A few pictures by email make the job easier to understand, and we’ll come back to you with a quote.
Thankerton buildings and the weather
Private landlords in Scotland must meet the Repairing Standard, which includes keeping a home wind and watertight, and sound outside sealant is part of that. Harled (roughcast) walls are common in Scotland, and where harling meets frames, pipes and other materials, the joint needs a flexible sealant that grips a rough surface.
Letting a property close to Carstairs station? Then split movement joints are easy to miss on a rental until damp shows inside.
Thankerton is about 11 miles south-east of Carluke, in South Lanarkshire. For external mastic in and around Thankerton, it’s easy to get a quote: please drop us a line at info@mrmastic.co.uk. We’re based in Crawley and cover South Lanarkshire, Thankerton included. Thankerton is one of 139 places in South Lanarkshire where we work. Edinburgh is on our list too, about 27 miles from Thankerton.
We cover every part of ML12 for external mastic and the streets around it. You’ll find streets such as Mill Road, Millands Road and Boat Road, all of which we cover. Close by, we work in Covington (1 mile north), Pettinain (3 miles north-west), Libberton (3 miles north), Carstairs Junction (5 miles north) and Carnwath (5 miles north). Within a short drive, we also cover Larkhall (15 miles north-west), Carluke (11 miles north-west), Lanark (6 miles north-west), Stonehouse (15 miles west), Lesmahagow (10 miles west) and Law (13 miles north-west).
What’s near Thankerton
Thankerton’s nearest station is Carstairs station, roughly 4.7 miles north. Well-known places in the area include Covington School Museum (0.9 miles north) and Fatlips Castle (2.6 miles south).
How it works
Most of a good job is in the preparation, so that’s where we spend the time. Every joint is cleaned and dried before new material goes in. All told, the work takes a few hours for a handful of joints, longer for a whole elevation. Outside jobs in Thankerton need a dry day, because sealant won’t bond to a wet joint, so external jobs may need to move if the day turns wet. Indoor work goes ahead whatever the weather.
- We start by walking round the building and agreeing the joints and the access.
- Every bit of old sealant and any mortar or debris is cut out.
- Joint faces are cleaned back and primed if the sealant needs it.
- We fit closed-cell backing rod to control the depth.
- We apply the sealant, tool it and check the whole run.
How to prepare
- Move anything stored near the joints
- Mention if the joints have been sealed before
- Let us know about parking restrictions
Get a quote
For a quote, drop us a line at info@mrmastic.co.uk with the location and a short description of the problem. You’ll have a clear quote before any work starts.
Advice
How to look after the new joints
To keep the joints looking good and working properly:
- Keep high-pressure jets off the joints
- Keep soil, plants and ivy away from the joints
- Keep movement joints as flexible joints, not mortar
- Check the sealant is paintable before painting near it
Don’t let soil, plants or ivy build up against the new joints. Damp material against the sealant shortens its life.
If you can see gaps, plants or bare sections in a joint, have it checked. Earlier resealing means a smaller job and a better result.
More services for Thankerton
Leave it or put it right?
A failed movement joint lets water into the wall, behind render and cladding. Resealing early keeps the job to the joint itself, instead of the wall and finishes around it. Around Thankerton, water from a failed joint in an older stone home can soak into timber and plaster, which is a far bigger job than the sealant.
No two jobs are quite the same, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all make a difference.
Why choose Mr Mastic in Thankerton
- Any old sealant cut out fully, not covered over
- White, clear, grey or coloured to suit, where the product allows
- Rated 4.9 stars on Google
- We’re fully insured
See what affects the cost and what customers say.