Highland · Scotland
Castletown Window Mastic
Mastic around window and door frames, sills and patio doors for householders, landlords and businesses in Castletown. ARBOMaster approved applicators, fully insured, with a 12-month guarantee.
- Draughts coming in around windows and doors
- Gaps left after new windows were fitted
- Old mastic that has gone black or come away
Window mastic in Castletown
Around Castletown we seal all kinds of frames: uPVC, aluminium, timber and composite, along with patio doors, French doors and sills. Each gets a sealant chosen for the frame and the wall it meets. If you have cracked sealant at the sill ends and draughts coming in around windows and doors, we can put it right, on timber windows & doors, patio & French doors and window sills alike.
Older stone-built homes in Scotland often have sash and case or timber windows set in stone. The sealant has to suit the stone, which rules out acetoxy silicones that can mark or attack it.
A 12-month guarantee comes as standard.
- Place
- Castletown (KW14)
- Wider area
- Highland
- Cover
- One year on every job
- Quote
- Quoted before any work starts
- info@mrmastic.co.uk
- Last updated
- 26 October 2026
Why act early in Castletown
Draughts and leaks don’t always mean new windows. Where the frames are sound, new mastic usually deals with draughts and leaks at the edges. Problems with the glass or gaskets are for a window company, and we will say so. 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.
Doing several joints on one visit is generally more efficient than separate visits. You will get one clear quote for the whole job.
Why us?
- Quality sealants from Arbo and Everbuild
- Homes, businesses and hotels
- Anti-fungal sanitary silicone in wet areas
- A choice of colours where the product allows
See our cost guide and customer reviews.
What window mastic looks like in Castletown
Castletown is close to the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. That’s hard on the mastic around window and door frames, especially on the side facing the sea. Sash and case windows are common in older Scottish homes, and the joint between the box frame and the stone or render is traditionally pointed with sand mastic.
In the older streets around St Trothan's Church, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Castletown is about 5 miles east of Thurso, in Highland. Across the KW14 area, we cover window mastic for homes and businesses. Castletown is one of 253 places in Highland where we work.
Every address in KW14 is covered for window mastic, from the main roads to the quietest streets. You’ll find streets such as Calder Square, Main Street and Traill Street, and we cover them all. Other places close to Castletown include Murkle (2 miles west), Dunnet (3 miles north-east), Brough (4 miles north), Bower (4 miles south-east) and Thurso (5 miles west). Remote and island addresses need a little more planning, so tell us where you are when you ask for a quote.
Near you in Castletown
A little further out are Thurso Castle (4.4 miles west) and Dunbar Hospital (5.5 miles west). The countryside around Castletown includes St John's Loch.
Keeping the joints in good condition
So the new joints stay in good condition:
- Wash the frames with mild soapy water
- Keep timber frames painted
- Paint up to the joint, not over it
- Air rooms to keep condensation down around windows
Silicone cannot normally be painted, so if you’re planning to paint the frames or walls, tell us beforehand. We can use a paintable sealant where that matters.
Wet, windy weather is when failed mastic shows itself, but sealant goes on best when frames and walls are dry. Dealing with it when you first notice a crack avoids chasing leaks through the wet months.
Quotes for window mastic in Castletown
Every job gets its own quote. These are the things that affect it:
- The old material and how stubborn it is
- The product the joint needs
- How many rooms, windows or areas are involved
- Mould in or behind the old joints
Rather than a set price list, we price the job in front of us: the amount of work, the old material and the access. The price is agreed before we begin.
Asking for a quote
When you call or email, it’s useful to know:
- Where the property is
- Access, such as stairs, a lift or height
- If it’s domestic, commercial or a hotel
- Pictures of the joints, sent by email
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is, and add photos by email if you can.
Other services in Castletown
Work for landlords, hotels and businesses
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
Whether it’s one flat or a portfolio, you get the same standard of work: the old material taken out, careful preparation and a 12-month guarantee.
How it works
On the day, we look over the joints with you first. Surfaces next to the work are protected before any work begins. Most jobs take a morning for a couple of windows and a door. Outside jobs in Castletown need a dry day, because sealant won’t bond to a wet joint, so an outdoor job can move if the forecast changes. Indoor work goes ahead whatever the weather.
- First, we confirm safe access to each frame.
- Old, cracked mastic is removed completely.
- Frame and wall are cleaned and must be dry before sealing, and primed where the sealant calls for it.
- Deep voids are backed, then the sealant is gunned in.
- We tool the joint so water runs off, then clear up.
Getting ready for the visit
- For indoor joints, keep the area dry beforehand if you can
- Mention any tricky access
- Move anything stored near the joints
Get a quote
Every job is quoted individually, so start by telling us what you need. Simply email us at info@mrmastic.co.uk and describe the job, and photos are welcome.
Related advice
What we’re called out for in Castletown
Joints that are too thin or too deep fail early. A skim of sealant over a wide gap soon tears, and a gap filled solid cannot flex. That’s what backing rod is for.
The problems people usually mention when they call are:
- Rain getting in at the frame or under the sill
- Cracked internal joints between frame and plaster
- Whistling draughts around closed windows
- Sealant in the wrong colour for the frame
Around Castletown, as everywhere, window mastic is only as good as the preparation behind it.
Questions to ask before you book
- Who turns up on the day
- What insurance they hold
- What the cure time is
- Which colour the sealant will be
Honest limits
Before you book, it’s worth knowing the limits too:
- Faulty window hardware
- Misting between the panes of a double-glazed unit (that needs a new unit)
- Penetrating damp from a failed cavity tray or render
If you’re not sure, just drop us a line at info@mrmastic.co.uk and we’ll give you a straight answer.
Joints and surfaces we work on
- Window sills
- uPVC windows
- Patio & French doors
- Aluminium frames
- Composite doors
- Timber windows & doors
FAQs for Castletown
Does living near the coast affect window mastic in Castletown?
Near the coast, wind-driven rain and, nearer the shore, salt air make outside sealant work harder. The right product, a clean joint and the right depth all help it cope.
Will you come out to Castletown?
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 get sealant to suit coloured frames?
Yes. We can use white, brown, anthracite grey, black or clear.
Can landlords and businesses book you?
Yes, regularly. Several properties can be quoted together.
Can resealing stop a draught around my window?
Yes, where the draught is at the frame edge. We find where the air is coming from before we reseal.
Can you quote for more than one area?
Of course. Doing several areas at once is usually more efficient.
Will there be a smell?
That depends on the sealant. Some products have a noticeable smell, others very little, and any smell fades as they cure.
How much does window mastic cost in Castletown?
Every job is different, so each one gets its own quote. For a quick quote, send an email to info@mrmastic.co.uk and let us know what needs doing and where.