Windsor and Maidenhead · England
Sand Mastic in Windsor
Sand mastic in Windsor from a team with over 20 years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Crumbling sand mastic round a window
- Mastic worn away on windows facing the weather
- Draughts and rain around sash boxes
What we are called out for in Windsor
Age is the main cause. Even well-laid mastic needs renewing in time, depending on exposure and upkeep.
It’s worth asking for a quote if you see:
- Old sand mastic that has cracked, crumbled or fallen out
- Modern sealant on a period surround
- Draughty sash windows at the surround
- Window mastic to renew ahead of painting
If you let a flat or house near Windsor & Eton Central station, any sash windows need sound mastic to keep draughts and rain out.
Questions to ask before you book
- When the joint can take water or movement
- Is the old sealant removed completely?
- The length of the guarantee
- What product goes in the joint
How we handle sand mastic in Windsor
A silicone bead around a sash window can look out of place and is not always the right material. Sand mastic gives a finish that matches the age of the house, and we can replace one with the other. If you’re dealing with open joints round the window box and a silicone bead on a sash window that spoils the look, we can put it right, on tenement windows, brick reveals and timber door frames alike.
In a town like Windsor, older houses sit alongside newer estates, with windows of every age. In every case, the joint between frame and wall is what keeps water out.
Each job carries a 12-month guarantee.
- Location
- Windsor (SL4)
- Region
- Windsor and Maidenhead
- Cover
- A year, on every job
- Price
- Quoted before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
What the job involves on each surface
Period and listed homes
Materials matter on listed and conservation-area homes. Sand mastic is often the preferred finish.
Sash and case windows
Most of our sand mastic work is on sash windows. Each joint round the box is raked out and renewed.
More services for Windsor
What sand mastic looks like in Windsor
The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. With historic houses such as St Leonard's Hill (about 1 mile south-west) nearby, there’s older building stock in the area around Windsor as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
Homes close to All Saints Church include some older properties, and frames set in older brick or stone need a sealant that suits the wall as well as the frame. If you look after a building such as St Edward's Catholic First School, its window and door frames need their mastic kept sound, just like a home’s.
Windsor is about 3 miles south of Slough, in Windsor and Maidenhead. Our applicators cover sand mastic for homes and businesses in Windsor and the surrounding area. Our Windsor and Maidenhead coverage runs to 57 places, and Windsor is one of them. There’s also a page for Reading, about 15 miles away.
Our applicators cover all of the SL4 postcode area for sand mastic and the streets around it. Sand mastic is available to properties on Athlone Square, Leigh Square and Furness Square. With the A308 and A332 close by, Windsor is easy for our applicators to reach for sand mastic. Close by, we work in Clewer (1 mile north), Dedworth (1 mile west), Boveney (1 mile north-west), Eton Wick (1 mile north) and Oakley Green (1 mile west). We also work in nearby towns such as Maidenhead (5 miles north-west), Boyn Hill (5 miles north-west), North Ascot (5 miles south-west), Cookham (7 miles north-west), Furze Platt (6 miles north-west) and Broomhall (6 miles south). Windsor is among the bigger towns we cover in Windsor and Maidenhead.
Landmarks near Windsor
In Windsor, that means homes and buildings near The Prince Albert pub, Windsor Girls' School and Sutherland Grange. For rail, the closest station is Windsor & Eton Central station, roughly 1 mile north-east of the centre. Other landmarks nearby include Berkshire Yeomanry Museum (1 mile south-east) and Windsor Castle (1.3 miles east). Green spaces nearby include Bray Pit and Taplow Lake.
Aftercare tips
So the new joints stay in good condition:
- Look over the window mastic once a year
- Ask a joiner to look at soft timber first
- Keep modern sealant off the mastic
- Sort the mastic before the decorators arrive
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.
Why it’s worth doing now in Windsor
Replacing sash windows is a big decision for a period home, and in listed buildings it may need consent. If the frames are sound, renewing the mastic deals with gaps and draughts at the surround. Draughts from a gap round a frame, damp under a sill or water behind a bath panel all start small, and they’re far easier to fix early.
A failed joint rarely gets cheaper to fix by waiting, as water and mould keep getting in. If you’re unsure, ring 0345 464 0079 or send us an email and we’ll give you an honest view and a quote.
Why Windsor customers choose us
- Homes, businesses and hotels
- Fully insured
- We leave the area clean and tidy
- Over 20 years’ experience
Take a look at what affects the cost or our reviews.
When it is not the sealant
We’d rather tell you now than do work that won’t last, so here’s what sealant cannot put right:
- Decayed frames that need repair
- Damaged stone surrounds
- Whether work needs listed building consent
If you’re not sure, just ring 0345 464 0079 or send us an email and we will give you a straight answer.
What we seal
- Sash and case windows
- Period & listed homes
- Timber door frames
- Tenement windows
- Stone surrounds
- Brick reveals
FAQs for Windsor
Is sand mastic in Windsor guaranteed?
All our work, in Windsor and everywhere else, comes with a 12-month guarantee. We are fully insured, and an ARBOMaster approved applicator.
Is Windsor in your area for sand mastic?
Yes, Windsor is within the area we cover. We work across London and the South East. You can ring 0345 464 0079 or email us and tell us what needs doing, and we’ll give you a clear quote.
Are you fully insured?
Yes. We’re fully insured for domestic and commercial work.
Where do you work from?
We’re a Crawley-based firm, with over 20 years’ experience. Our area covers South East England, London and Scotland.
How long does the job take?
A typical job takes anything from a few hours to a full day, depending on how many windows. Your quote will say how long we expect yours to take.
Is it possible to take out silicone and use sand mastic instead?
Yes, we do this often. The old silicone has to come out completely so the mastic can sit properly.
Can tenants book the work?
We can work for tenants, landlords or agents. Get your landlord’s agreement first.
Can I do it myself?
Sometimes. Preparation is everything: all the old sealant out, and a clean, dry joint. We can always put it right if it fails.
What happens on the day
The work is kept neat and contained to the joints we’re treating, so you can get on with your day. The job normally takes a few hours per window, depending on the condition of the joints, and we tell you how long to leave it before we go. A visit in Windsor needs access to the work and a place to park close by. For outside work, let us know about side access, gates and any upper-floor joints.
- We look at the surrounds with you and agree the joints to renew.
- Old mastic and any loose material are raked out.
- Deep gaps are packed so the mastic sits at the right depth.
- The sand mastic is mixed and pressed into the joint by hand.
- We dress the finish so it sits neatly against the masonry.
Getting ready for the visit
- Let us know about earlier repairs to the joints
- For business premises, tell us about site rules or sign-in
- Let us know about stairs, lifts or work at height
Get a quote
For sand mastic in Windsor, call 0345 464 0079 or send us an email. A short description of the job and where it is helps us quote, and you will get a clear quote before work begins.
Read more
DIY versus a professional finish
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions.
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.