Highland · Scotland
Lewiston External Mastic
We cover Lewiston for sealing brickwork movement joints, render, cladding and façade joints. Old material cut out, joints cleaned and sealed neatly and a one-year guarantee.
- Sealant pulling away from one side of the joint
- Rigid filler in a joint that should flex
- Movement joints with cracked, split or missing sealant
External mastic for homes and businesses in Lewiston
On houses, flats and commercial buildings across Lewiston, we reseal joints in brickwork, render, cladding and façade panels. Every joint gets the same careful preparation: clean joint faces and the right depth. If you have joints with sealant missing in places and weathered mastic that no longer stretches, we can help.
Stone walls need a stone-friendly sealant, as acetoxy products can attack some stone. On newer homes, the movement joints and roofline trims are what need watching.
All of our work is guaranteed for twelve months, and the guarantee is the same wherever you are.
- Where
- Lewiston (IV63)
- Wider area
- Highland
- Cover
- One year on every job
- Quotes
- A clear quote up front
- info@mrmastic.co.uk
- Updated
- 26 October 2026
External mastic in Lewiston: local notes
Under the Repairing Standard, private landlords in Scotland have to keep homes wind and watertight, and failed outside joints work against that. With historic houses such as Boleskine House (about 4.4 miles south) nearby, there’s older building stock in the area around Lewiston as well as newer homes. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth.
Homes close to Kilmore Parish Church of Scotland include some older properties, and the joints between older walls, newer extensions and the roofline need a sealant that can move.
Lewiston is about 13 miles south-west of Inverness, in Highland. Across the IV63 area, our applicators can take on external mastic. Our area takes in 253 places across Highland, large and small.
Postcode districts we cover here for external mastic: IV63. External mastic is available to properties on Dal of Borlum, Carn Glas and Carriers Croft and the roads around them. We also cover the places around Lewiston: Drumnadrochit (1 mile north), Torness (4 miles east), Gorthleck (6 miles south), Dores (7 miles north-east) and Kiltarlity (8 miles north). Larger places within reach include Inverness (13 miles north-east), Merkinch (14 miles north-east), Hilton (13 miles north-east), Crown (14 miles north-east), Millburn (14 miles north-east) and Muir of Ord (13 miles north). Remote and island addresses need a little more planning, so please mention your location when you drop us a line at info@mrmastic.co.uk.
Near you in Lewiston
We work in homes and buildings around Drumnadrochit Hotel. A little further out are Urquhart Castle (1.3 miles east) and Urquhart Castle Visitor Centre (1.2 miles east). Open spaces near Lewiston include Loch Ness.
What happens on the day
The work is kept neat and contained to the joints we’re treating, so you can carry on as normal. Expect the work to take a few hours to a few days, depending on the length of joint and the access, and we tell you how long to leave it before we go. Outdoor work around Lewiston depends on the weather, as sealant needs a dry surface, so an outdoor job can move if the forecast changes. Indoor work goes ahead whatever the weather.
- Each joint is checked and the colour of the new sealant agreed.
- We take out the old sealant until the faces are sound.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- We prime the faces where required.
- We gun in low-modulus sealant and tool it neatly.
Getting ready for the visit
- Let us know about stairs, lifts or work at height
- Let us know about earlier repairs to the joints
- Tell us about any water getting in
Getting a quote
If you’re in Lewiston and need external mastic, drop us a line at info@mrmastic.co.uk. A short description of the job and where it is helps us quote, and we will agree the price before any work begins.
Advice
When something else is needed
Sealant isn’t the answer to every problem, and we will tell you before work begins. It will not solve:
- Failed render or damaged cladding panels
- Damp that isn’t coming from the joint
- Structural movement, which needs a surveyor or engineer
Not sure which it is? You can send an email to info@mrmastic.co.uk and we will tell you honestly before you book.
Joints and surfaces we work on
- Brickwork movement joints
- Render & cladding joints
- Joints between brick and frames
- Concrete & block
- Façade panels
- Copings & trims
DIY sealant or a professional job?
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
How we quote for external mastic
Jobs vary more than people expect. The main factors:
- How many areas need sealing
- Mould in or behind the old joints
- Whether old sealant or filler has to be cut out
- Access and height
The cost depends on the size of the job, how much old material has to come out and access to the work. You will have a clear quote before any work starts, so you know where you stand.
Helping us quote
What to tell us when you ask for a quote:
- Access, such as stairs, a lift or height
- Roughly how big the job is
- Pictures of the joints, sent by email
- Where the job is, and your postcode
Getting a quote is simple: tell us what needs doing and where and its rough size. Photos by email help us understand the job, and we’ll take it from there.
Why act early in Lewiston
Water gets in through a failed movement joint. Dealing with it early keeps the repair to the joint, instead of the wall and finishes around it. In an older home around Lewiston, damp from a failed joint can get into timber and plaster.
A failed joint rarely gets cheaper to fix by waiting, as water and mould keep getting in. If you are not sure whether it needs doing, drop us a line at info@mrmastic.co.uk and we will give you an honest view and a quote.
Why Lewiston clients choose us
- Sanitary silicone with an anti-fungal additive in wet areas
- Any old sealant cut out fully, not covered over
- Colour agreed with you before we start
- One-year guarantee on every job
Common questions in Lewiston
Is Lewiston within the area you cover?
Yes, smaller places are covered as well as towns. Our work covers the whole of Scotland. Let us know about access, parking and anything unusual about getting there when you book.
Can you do external mastic in Lewiston?
Yes, Lewiston is within the area we cover. We work across all of Scotland. You can email us at info@mrmastic.co.uk and let us know what needs doing, and we will send you a clear quote.
Can you seal joints between two different materials?
Yes. We cut out the old sealant, prepare both faces and reseal with a flexible exterior product. We pick a colour that works with both materials.
How long does the job take?
As a guide, most jobs take a few hours to a few days, depending on the length of joint and the access. Bigger jobs take longer, and we will tell you how long to expect.
Why do you put foam in the joint first?
We fit closed-cell backing rod wherever the joint depth needs controlling. It controls the depth and stops the sealant bonding to the back.
Can a movement joint be filled with mortar?
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.
Do you work for landlords and businesses?
Yes. We work for householders, landlords, letting agents, businesses and hotels across Highland.
Why is there a gap in my brick wall?
Most straight vertical gaps in brickwork are movement joints. It gives the wall room to move.
Common problems we fix in Lewiston
Buildings move more than people expect. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. All of that ends up in the joint sealant.
The most common problems we see are:
- Sealant pulling away from one side of the joint
- Movement joints filled with mortar instead of sealant
- Plants rooting in failed movement joints
- Leaking joints around cladding and façade panels
Schools such as Glen Urquhart High School are buildings too, and movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
What your quote should include
- What happens if they find a problem under the old sealant
- What product goes in the joint
- Whether you can choose the colour
- Is the old sealant removed completely?
Also near Lewiston
Other services in Lewiston
Aftercare tips
Aftercare is simple:
- Walk round the building once a year and look at the joints
- Keep soil, plants and ivy away from the joints
- Make sure movement joints aren’t pointed over
- Have failed joints looked at early
Only paint over the joint if we’ve confirmed the sealant can take paint. Many exterior sealants are not designed to be painted.
A joint that has stopped moving pushes the movement elsewhere, often as cracks near the joint. Resealing it early helps prevent that.