Windsor and Maidenhead · England
Sand mastic for sash & case windows in Cheapside, Windsor and Maidenhead
Professional sand mastic in and around Cheapside, with old sealant always removed completely and a one-year guarantee.
- Mastic worn away on windows facing the weather
- Old sand mastic that has cracked, crumbled or fallen out
- Cracked mastic round a front door frame
Keeping the joints in good condition
Good habits help new joints last longer. Our tips:
- Clear gutters so water does not pour onto the windows
- Do not run silicone over sand mastic
- Check the mastic when you check the paintwork
- Ask us before painting near the mastic
Don’t touch or press the mastic while it hardens. It skins over quickly but needs longer to fully harden.
Crumbling mastic lets rain into the joint. That water can reach the timber frame and the wall, so renewing it early is worth it.
Sand mastic for homes and businesses in Cheapside
Sand mastic is the traditional way to point the gap between a timber window frame and the stone or brick around it. It’s made from sand and a linseed-oil-based binder and built up by hand. On older homes, it suits the building far better than silicone. If you’re dealing with mastic worn away on windows facing the weather and gaps where the frame meets the masonry, we can help, whatever the surface.
Outdoor sealant needs dry, clean surfaces, so work on frames around Cheapside is planned for dry weather. Let us know about access to all the frames, upstairs ones included.
Big or small, it’s backed by our one-year guarantee.
- Where
- Cheapside (SL5)
- Wider area
- Windsor and Maidenhead
- Guarantee
- 12 months on all our work
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Surface by surface
Sash and case windows
The mastic round a sash window is on show so we finish it carefully.
Brick reveals
Sand mastic is also used where timber frames meet brick. It suits older brickwork.
What happens if it’s left?
A silicone bead can be quicker, but on period stone or brick it often looks out of place. Sand mastic is the traditional material and blends with the stone or brick. Around Cheapside, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
A failed joint rarely gets cheaper to fix by waiting, because water and mould keep working on it. If you’re not sure whether it needs doing, phone 0345 464 0079 or send us an email and we’ll give you an honest view and a quote.
What you get with us
- 4.9 on Google from 180+ five-star reviews
- An ARBOMaster approved applicator
- 20+ years of sealant experience
- Experience in homes, commercial sites and hotels
See our cost guide or customer reviews.
What affects the quote in Cheapside
Call for a quick quote. The main things that affect it are:
- How easy the joints are to reach
- Working hours on commercial sites
- How much old sealant there is and how hard it is to remove
- How much there is to do
Combining jobs into one visit is generally more efficient than separate visits, so tell us about everything that needs sealing. We will give you a clear price for the lot.
What to tell us for a quote
To make quoting easier, let us know:
- What the problem is, such as mould, gaps, leaks or cracking
- Whether it has been sealed before
- Where the job is, and your postcode
- Access, such as stairs, a lift or height
Call for a quick quote, or email us if that’s easier. Describe what needs sealing and we will talk you through the work and send you a clear quote.
Can I do it myself?
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
The biggest DIY mistake is sealing over old sealant. Silicone doesn’t stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
FAQs for Cheapside
Can you do sand mastic in Cheapside?
Yes, Cheapside is within the area we cover. We work across London and the South East. You can call 0345 464 0079 or email us and tell us what needs doing, and we’ll give you a clear quote.
I let a flat near Ascot station. Can you help?
Yes, we work for landlords and letting agents. Just call 0345 464 0079 or email us and tell us about the property, and we will give you a clear price.
How do I get a quote for sand mastic in Cheapside?
Every job is different, so each one gets its own quote. To get one, call 0345 464 0079 or email us with a short description of the job.
Where do you work from?
We are based in Crawley, West Sussex, and we cover South East England, London and all of Scotland.
What is sand mastic?
Sand plus a binder based on linseed oil. It’s applied by hand and finished to sit neatly against the masonry.
Is it possible to paint over sand mastic?
The usual advice is to leave sand mastic unpainted. Ask us before you decorate around it and we will advise.
How long does the job take?
That depends on how much there is to do, but as a guide it takes anything from a few hours to a full day, depending on how many windows. We will tell you when we quote.
Is sand mastic better than silicone for my windows?
That depends on your windows. On many period windows, sand mastic looks right and suits the building, while modern frames normally get a flexible sealant.
Signs you need sand mastic in Cheapside
Paint, silicone or cement used over old mastic causes problems. They do not suit the joint, and they normally need raking out.
Most people get in touch after spotting something like this:
- Old cement repairs round a window that have failed
- Weathered mastic on the most exposed windows
- Crumbling sand mastic round a window
- Mastic that needs renewing before redecorating
For landlords with property near Ascot station, older sash windows in a rental need their mastic kept sound to keep the weather out.
Questions to ask before booking
- Whether you can choose the colour
- What happens if the job turns out different
- Whether all the old sealant comes out first
- How long the guarantee is
Places near Cheapside
Also in Cheapside
Sand mastic in Cheapside: local notes
Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. With historic houses such as St Leonard's Hill (about 3.4 miles north) nearby, there’s older building stock in the area around Cheapside as well as newer homes. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window.
Managing a site like Cheapside CofE Primary School? Then its window and door frames need their mastic kept sound, just like a home’s. If you live in an older home near Church of St Michael and All Angels, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Cheapside is about 4 miles south of Windsor, in Windsor and Maidenhead. Jobs in Cheapside get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Cheapside is one of 57 towns and villages in Windsor and Maidenhead we cover for sand mastic. Our Reading page covers work nearby (14 miles or so).
Our applicators cover all of the SL5 postcode area for sand mastic and the streets around it. Streets in the area include Water Splash Lane, Dorian Drive and Cheapside Road. We also cover the places around Cheapside: Beggar's Bush (1 mile south-east), Ascot (1 mile south-west), Blacknest (1 mile south-east), Woodside (1 mile north-west) and Sunninghill (1 mile south). Further out, we also cover Maidenhead (8 miles north-west), Windsor (4 miles north), Boyn Hill (7 miles north-west), Cookham (10 miles north), Furze Platt (9 miles north-west) and Dedworth (4 miles north).
Around Cheapside
Locally, jobs take us to homes and businesses close to Papplewick School, Charters School and Thatched Tavern Public House, among other places. For rail, the closest station is Ascot station, about 1.6 miles south-west. Nearby you will also find Heatherwood Hospital (1.8 miles west) and Berkshire Yeomanry Museum (3.9 miles north-east). Open spaces near Cheapside include Virginia Water Lake and Gracious Pond.
What we do, step by step
We keep the work tidy and contained to the area we are working on, so you can get on with your day. Expect the work to take anything from a few hours to a full day, depending on how many windows, and we tell you how long to leave it before we go. Somewhere like Cheapside needs a little journey planning: tell us about narrow lanes, gates, long drives and where we can park. We bring what the job needs, so it can be finished in one trip where possible.
- Each surround is checked first.
- We rake out the old mastic and clean the joint.
- We fill deep gaps so the new mastic isn’t too thick.
- We point the joint with sand mastic by hand.
- The finish is dressed neatly.
Preparing for the visit
- Keep children and pets away from the work area
- Mention any leaks or damp you’ve noticed
- Mention any sign-in or site rules at work premises
Get a quote
Every job is quoted individually, so start by telling us what you need. Simply call 0345 464 0079 or send us an email and describe the job and send photos if you have them.