Isle of Wight · England
Sand mastic for sash & case windows in Great Thorness, Isle of Wight
Our applicators work in Great Thorness on traditional burnt sand mastic around sash and case windows and doors in stone and brick. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Crumbling sand mastic round a window
- Old cement repairs round a window that have failed
- A silicone bead on a sash window that spoils the look
Sand mastic in Great Thorness
A silicone bead around a sash window can look out of place and doesn’t suit the building. Sand mastic gives a finish that matches the age of the house, and we can replace one with the other. We work on sash and case windows, brick reveals and period & listed homes, and common reasons people get in touch are draughts and rain around sash boxes and patchy fillers round a sash window.
Homes in small places like Great Thorness often stand in the open, with little to shelter their windows from wind and rain. That exposure dries out and cracks the mastic around frames and sills faster.
You get a 12-month guarantee, the same in Great Thorness as everywhere else we work.
- Where
- Great Thorness (PO31)
- Wider area
- Isle of Wight
- Guarantee
- 12 months on all our work
- Quote
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
How to look after the new joints
Once the sealant has cured, a few habits help it last:
- Avoid patching sand mastic with silicone
- Ask a joiner to look at soft timber first
- Keep sills and gutters clear so water drains away
- Ask the planning authority about consent for listed or conservation-area homes
Do not run silicone over the new mastic. If anything cracks, get it looked at rather than patching it.
Gaps round a sash box let in draughts and rain. Left, the gap tends to get bigger as more mastic falls out.
Great Thorness questions
Do you cover Great Thorness for sand mastic?
Yes. Our work covers London and the South East, and Great Thorness is part of that. You can call 0345 464 0079 or drop us an email and let us know what needs doing.
Will you come out to Great Thorness?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
When will the new mastic be hard?
A skin forms quite soon, but full hardening takes longer. We’ll tell you what to expect for your job.
Does someone need to be in?
That depends on where the joints are. Inside work needs someone to give us access.
What sealant do you use?
The product depends on the job: sanitary silicone where it gets wet, and sealants suited to movement or weather elsewhere. We use products from Arbo and Everbuild.
Do you work for letting agents?
Yes. Domestic, commercial and hotel work are all part of what we do.
Can you seal over the old sealant?
No, it won’t last. It can look neat for a few weeks, but the new layer lifts away from the old one. The old sealant has to come out completely.
Will you leave a mess?
Very little: the area around the joints is protected first, and we clear up the old sealant and our materials before we leave.
Can I do it myself?
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and doesn’t move well, and getting the depth right matters as much as the look.
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 sand mastic looks like in Great Thorness
Great Thorness is within about 1 mile of 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. Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
In and around Great Thorness, as anywhere, good sand mastic starts with a clean, dry, properly prepared joint. Historic houses such as Swainston Manor, about 3 miles south, show how far back building around Great Thorness goes.
Great Thorness is about 3 miles south-west of Cowes, in the Isle of Wight. If you need sand mastic in Great Thorness, it’s easy to get a quote: please ring 0345 464 0079 or email us. We cover the Isle of Wight from our Crawley base, Great Thorness included. Great Thorness is one of 125 towns and villages in the Isle of Wight we cover for sand mastic. Southampton is on our list too, about 13 miles from Great Thorness.
Here we cover the PO31 postcode area for sand mastic. If you are just outside Great Thorness, we cover Porchfield (1 mile south-west), Locksgreen (1 mile south-west), Rew Street (2 miles north-east), Newtown (2 miles south-west) and Northwood (2 miles north-east). Within a short drive, we also cover Newport (3 miles south-east), Ryde (9 miles east), Cowes (3 miles north-east), Sandown (10 miles south-east), Shanklin (10 miles south-east) and Ventnor (11 miles south-east). Remote and island addresses need a little more planning, so please mention your location when you call 0345 464 0079 or drop us an email.
Around Great Thorness
We work in homes and buildings around Sportsman's Rest pub. Nearby you will also find Carisbrooke Castle (3.5 miles south-east) and St Mary's Hospital (2.8 miles south-east). Open spaces near Great Thorness include Mill Hill.
Towns and villages near Great Thorness
Other services in Great Thorness
How the job changes by surface
Stone surrounds
Old stone surrounds are often uneven, so the gap isn’t the same all the way round. We shape it by hand to follow the stone.
Sash and case windows
The mastic round a sash window is on show, so a neat, even finish matters.
When something else is needed
To be straight with you, there are a few things sealant will not fix:
- Crumbling stone or brickwork round the window
- Timber that has rotted
- Whether work needs listed building consent
If in doubt, call 0345 464 0079 or send us an email and we’ll say what we think before booking.
Where we work in Great Thorness
- Period & listed homes
- Brick reveals
- Stone surrounds
- Timber door frames
- Tenement windows
- Sash and case windows
Landlords, agents and businesses in Great Thorness
Mouldy or split sealant often shows up at the end of a tenancy, and it’s easy to sort out between tenants. Several properties can be quoted together.
Water getting past a failed joint can damage the building, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance.
What happens on the day
You do not need to clear the whole room or building, just the space around the work. Everything nearby is protected, and the job takes a few hours for a single window, longer for several for a typical job. Somewhere as small as Great Thorness, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- We check the window surrounds and agree which joints need renewing.
- The loose and crumbling mastic is raked out and the joint cleaned.
- We pack any deep gaps so the mastic sits at the right depth.
- The mastic is mixed, pressed into the joint by hand and shaped.
- The finish is dressed so it sits neatly against the stone or brick.
Before we arrive
- Tell us about any previous sealing or DIY attempts
- Tell us about access, such as stairs, a lift or high-level joints
- Clear items away from the joints we’re working on
Get a quote
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is, and we’ll talk you through what we’d do. Whenever you’re ready, call 0345 464 0079 or email us.
Related advice
How we quote for sand mastic
The price is agreed before any work begins. It’s based on:
- How easy the joints are to reach
- Working hours on commercial sites
- The number of rooms or windows
- The size of the job
Commercial jobs are quoted on the same basis as homes: the amount of work, the access and the products needed, plus any working-time requirements on site. Ask us for a quote and we’ll go through it with you.
What to tell us for a quote
Photos help, but a description is a good start. Try to tell us:
- Whether it has been sealed before
- What the problem is, such as mould, gaps, leaks or cracking
- Access, such as stairs, a lift or height
- Whether it’s a home or a business
Every job is quoted individually, so start by telling us what you need. Simply call 0345 464 0079 or email us and describe the job.