West Dunbartonshire · Scotland
Window Mastic in Arrochar
Window and door frames in Arrochar need attention? We remove the old material, prepare the joints and seal them properly.
- Gaps where the sill meets the wall
- Damp patches on the reveal after heavy rain
- Mastic that is falling out in pieces
Window mastic in Arrochar, done properly
A cold draught around a closed window often comes from the frame edge. A new joint stops the air getting through. Where the air is getting in through the window itself, we will say so. If you are dealing with mastic that has split away from the wall and gaps left after new windows were fitted, we can put it right, whatever the surface.
Outdoor sealant needs a dry surface, so window work around Arrochar is planned around the weather. Tell us about access to all the windows and doors, upstairs included.
We guarantee the work for a year. If something is not right with it in that time, tell us and we will put it right.
- Place
- Arrochar (G83)
- Region
- West Dunbartonshire
- Guarantee
- A year, on every job
- Price
- A clear quote up front
- info@mrmastic.co.uk
- Page updated
- 26 October 2026
Should I try it myself first?
If you’ve already had a go yourself, that’s fine. We remove it and do the joint properly.
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
Also near Arrochar
Also in Arrochar
FAQs for Arrochar
Do you work for landlords with property near Arrochar & Tarbet station?
Yes. We work for landlords and letting agents as well as householders, and several properties can be quoted together. You can send an email to info@mrmastic.co.uk with the details for a clear quote.
Do you cover smaller places like Arrochar?
Yes, we do. We work across all of Scotland, from towns to the smallest places. The journey is planned ahead, so it helps to know about access.
Is it OK to seal over old sealant?
No. New silicone will not bond to old silicone, and anything trapped underneath, including mould and water, stays there. We remove it all first.
Can you do upstairs windows?
Generally, yes. We plan safe access before the job.
Are you ARBOMaster approved?
Yes. We hold ARBOMaster approved applicator status.
Can you get sealant to suit coloured frames?
Yes. We can use white, brown, anthracite grey, black or clear, so the joint suits the frame.
Do you do commercial work?
Yes. Commercial and hotel work is a large part of what we do, as well as homes. We can talk about working times when we quote.
Do you take out the old sealant first?
Yes. We cut out all the old sealant and clean the joint.
The process
All our tools and materials come with us in the van, so there’s nothing for you to buy. After a quick look at the joints together, the area is protected and the work begins. It normally takes a few hours for a few frames, or a day or more for a whole house. Outdoor work around Arrochar depends on the weather, as sealant needs a dry surface, so external jobs may need to move if the day turns wet. Work indoors isn’t affected.
- First, we confirm safe access to each frame.
- All the failed sealant is cut away.
- Frame and wall are cleaned and must be dry before sealing.
- Backing rod fills deep voids and the sealant goes in on top.
- The joint is shaped to shed water and the area tidied.
How to prepare
- Let us know about earlier repairs to the joints
- Where the joints are inside, avoid wetting them before we arrive
- Clear items away from the joints we are working on
Get a quote
It all starts with a short chat. Describe the problem, the location and the size of the job. When it suits you, send an email to info@mrmastic.co.uk.
Related advice
What we’re called out for in Arrochar
Mastic ages in the weather. UV light hardens the outside of the bead, until it loses its stretch and starts to crack.
These are the problems we are asked about most:
- Black, perished sealant on frames
- Sealant in the wrong colour for the frame
- Gaps where the sill meets the wall
- Whistling draughts around closed windows
For an older house near a landmark such as Arrochar Church, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint.
What your quote should include
- When the joint can take water or movement
- Is the old sealant removed completely?
- What the quote includes, VAT included or not
- How long the guarantee is
How we quote for window mastic
Your quote is based on your job. We take into account:
- Which sealant suits the joint
- How easy the joints are to reach
- The number and length of the joints
- Working hours on commercial sites
Homes and businesses are quoted the same way: the amount of work, the access and the products needed. Call for a quick quote and we’ll explain what it covers.
What to tell us for a quote
To help us quote quickly, let us know:
- Pictures of the joints, sent by email
- If someone has resealed it before
- Roughly how big the job is
- The problem you’ve noticed
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints, and add photos by email if you can.
Looking after it afterwards
Joint life depends on how it’s used and looked after. We suggest:
- Keep paint off silicone joints
- Repaint timber before it’s bare
- Don’t use solvent cleaners on the joint
- Don’t aim a pressure washer at the joints
Keep the new mastic undisturbed while it cures, following the cure time we give you. Keep jet washers away from the frames.
A failed joint lets water into the wall a little at a time. You might not see it until plaster blows or a damp patch appears inside. Catching it early keeps the fix to a reseal.
What window mastic looks like in Arrochar
Arrochar is close to the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. Both are hard on the mastic around window and door frames, which can dry out and crack sooner where a building faces the weather. The west of Scotland is wetter than the east, which means the mastic around window and door frames has to cope with a lot of rain.
Letting a property close to Arrochar & Tarbet station? Then sound mastic around windows and doors keeps out the draughts and damp that tenants notice first.
Arrochar (Gaelic: An t-Àrchar) is about 13 miles north of Helensburgh, in West Dunbartonshire. Every kind of property in Arrochar is covered for window mastic. Every job comes with our one-year guarantee. Our West Dunbartonshire coverage runs to 31 places, Arrochar among them. We also work in Glasgow, around 30 miles away.
Work in G83 is quoted and booked the same way as anywhere else. Window mastic is available to properties on Church Road, Beechwood and Macfarlane Drive and the roads around them. We also cover Succoth (1 mile north), Tarbet (1 mile north-east), An Tairbeart (2 miles north-east), Lochgoilhead (6 miles west) and Ardlui (7 miles north). Within a short drive, we also cover Alexandria (15 miles south-east), Balloch (15 miles south-east) and Jamestown (15 miles south-east).
Near you in Arrochar
The nearest railway station is Arrochar & Tarbet station, roughly 1 mile north-east of the centre. A little further out are Inveruglas Isle Castle (3.9 miles north). The countryside around Arrochar includes Loch Lomond.
Surface by surface
Timber windows & doors
Wood swells when it’s wet and shrinks when it dries, so the joint must stay flexible. We seal onto sound, dry paintwork or timber.
Composite doors
Composite doors are normally hung in an uPVC-type frame, and the joint around it is sealed like a window. We match the colour to the frame.
Why act early in Arrochar
Failed mastic is not a reason to replace sound windows. If the frames and glass are in good order, resealing the joints is often all that’s needed. If we find failed glass units or worn seals, we’ll tell you. When the nearest tradesperson is a drive away, it’s tempting to leave a small leak, but water behind a failed seal does the most damage when nobody’s watching.
The cost reflects the work involved, not guesswork. That’s why we ask a few questions first and give you a clear price before any work starts.
Why Arrochar customers choose us
- We agree the colour with you first
- We never seal over old sealant
- One-year guarantee on every job
- Fully insured
Take a look at how sealant jobs are priced or our reviews.