Highland · Scotland
Sand mastic for sash & case windows in Dunnet, Highland
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for householders, landlords and businesses in Dunnet. ARBOMaster approved applicators, fully insured, with a 12-month guarantee.
- Mastic dropping out of the joint
- Open joints round the window box
- Mastic worn away on windows facing the weather
Sand mastic in Dunnet, done properly
Sand mastic has long been used to fill the joint between timber frames and masonry. It’s a mix of sand and a linseed-oil-based binder, applied by hand. On period homes, it looks right where silicone wouldn’t. We work on sash and case windows, period & listed homes and tenement windows, and people most often call us about gaps where the frame meets the masonry and mastic dropping out of the joint.
In and around a place like Dunnet, homes range from older stone-built cottages to newer houses. Wind-driven rain finds any gap around a frame or sill, so the mastic there works hard.
Each job carries a 12-month guarantee.
- Location
- Dunnet (KW14)
- Wider area
- Highland
- Guarantee
- One year on every job
- Price
- Quoted before any work starts
- info@mrmastic.co.uk
- Last updated
- 26 October 2026
Surface by surface
Period and listed homes
Period homes look their best with traditional materials.
Sash and case windows
On a sash window, the mastic joint shows on the outside so we finish it carefully.
Common problems we fix in Dunnet
Water gets into small cracks in the mastic and loosens it further. Windows facing the weather tend to go first.
Any of these means the joints need attention:
- Weathered mastic on the most exposed windows
- Draughty sash windows at the surround
- Window mastic to renew ahead of painting
- Cement or filler used on old window joints that has cracked
Homes close to Dunnet Church include some older properties, and replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint.
Comparing quotes
- What guarantee comes with the work
- When the joint can take water or movement
- Whether the sealant suits the joint
- Whether all the old sealant comes out first
Common questions in Dunnet
Do you cover smaller places like Dunnet?
Yes, smaller places are covered as well as towns. Our work covers the whole of Scotland. Just mention lanes, gates or anything else about the route when you book.
Is sand mastic in a coastal place like Dunnet any different?
Coastal weather is harder on outside sealant: there’s more wind-driven rain and, closer to the shore, salt in the air. Choosing the right sealant for the frame and wall, laid at the right depth, helps it last.
Where is Mr Mastic based?
We work from Crawley. Our applicators cover Dunnet.
Do you have insurance?
Yes. We are fully insured.
Do you guarantee sand mastic work?
Our 12-month guarantee applies on every job.
Which is right for my windows, sand mastic or modern sealant?
We will talk it through with you. Period homes often look best with sand mastic, and modern sealants suit newer frames.
Do you work for landlords and businesses?
Yes. As well as householders, we work for landlords, agents, businesses and hotels in Dunnet.
Can I paint the new mastic?
It’s traditionally left unpainted, which is what traditional guidance recommends. Ask us before decorating.
What we do, step by step
Every visit runs the same way: we look at the joints together, mask and protect the surrounding surfaces, do the work and tidy away. Most jobs take a few hours per window, depending on the condition of the joints. For a place like Dunnet, longer drives are planned in advance. Mention tracks, gates, ferries or anything else about the route.
- First we agree which joints need doing.
- We remove the old, loose mastic.
- We pack any deep voids first.
- The sand mastic is mixed and pressed into the joint by hand.
- The surface is finished to suit the stone or brick.
Preparing for the visit
- Where the joints are inside, avoid wetting them before we arrive
- Let us know about parking restrictions
- For business premises, tell us about site rules or sign-in
Ask for a quote
For a quick quote, get us on the phone, or email us if that is easier. Describe what needs sealing and we’ll explain what’s involved and give you a clear quote.
Read more
What sand mastic looks like in Dunnet
Dunnet is close to the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. Both are hard on the mastic around older windows and doors, which can dry out and crack sooner where a building faces 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.
In and around Dunnet, as anywhere, good sand mastic starts with a clean, dry, properly prepared joint.
Dunnet is about 7 miles east of Thurso, in Highland. Homes, rented property, offices and hotels in Dunnet is covered for sand mastic. The work is guaranteed for a year. Dunnet is one of 253 places in Highland where we work.
Work in KW14 is quoted and booked the same way as anywhere else. Neighbouring places we cover for sand mastic include Brough (2 miles north), Castletown (3 miles south-west), Scarfskerry (3 miles north-east), Rattar (3 miles north-east) and Murkle (4 miles south-west). Remote and island addresses need a little more planning, so tell us where you are when you ask for a quote.
What’s near Dunnet
Other landmarks nearby include Westside Croft (0.5 miles north-west) and Castle of Mey (4.5 miles east). For a walk, there’s St John's Loch.
For landlords and businesses
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements and we’ll give you a quote.
Businesses can book us for washrooms, kitchens, offices and more. For commercial premises, we can talk through working times when we quote.
Also near Dunnet
Also in Dunnet
Should I try it myself first?
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and does not move well, and getting the depth right matters as much as the look.
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Looking after it afterwards
To keep the joints looking good and working properly:
- Go gently near the mastic when preparing windows
- Ask us before painting near the mastic
- Renew mastic before redecorating the windows
- Inspect the joints round the windows every year or so
Keep paint scrapers and sanders off the mastic when redecorating. Hard scraping can loosen it.
Good mastic helps keep the frame dry. Failed mastic lets water reach the timber and timber that stays wet can rot.
Why act early in Dunnet
New mastic over crumbling mastic won’t hold. We remove the loose material first so the new mastic stays put. Around Dunnet, 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.
Instead of a standard rate, we price the job in front of us: the amount of work, the old material and the access. You’ll know the price before we begin.
Why choose Mr Mastic in Dunnet
- Homes, businesses and hotels
- Arbo and Everbuild products
- Old sealant always removed completely
- Approved under the ARBOMaster scheme
Read what affects the cost and what customers say.