Medway · England
Sand Mastic in Dunn Street
Sand mastic for Dunn Street and the surrounding area: the right sealant, proper preparation and a neat finish. Ask us for a quick quote.
- Cement or filler used on old window joints that has cracked
- Tired mastic found when preparing windows for paint
- Cracked mastic round a front door frame
About our sand mastic in Dunn Street
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 are dealing with mastic round period door frames that has failed and cement or filler used on old window joints that has cracked, we can help, whatever the surface.
Around Dunn Street, many homes face open ground, so their windows and doors take the full weather. That exposure dries out and cracks the mastic around frames and sills faster.
Whatever the size of the job, it’s backed by our 12-month guarantee.
- Location
- Dunn Street (ME7)
- Wider area
- Medway
- Cover
- 12 months on all our work
- Quotes
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Why deal with it now?
Silicone might seem the quicker option, but it can look wrong on a period surround. Sand mastic suits the building and finishes neatly against the masonry. Around Dunn Street, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
No two jobs are quite the same, so we quote each one individually. Size, access and the product the joint needs all make a difference.
Why us?
- Neat joints and a tidy finish
- Approved under the ARBOMaster scheme
- Over 20 years’ experience
- 4.9 on Google from 180+ five-star reviews
Read what affects the cost and our reviews.
Also near Dunn Street
Also in Dunn Street
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 chosen for how the joint moves and where it is, and the work is guaranteed for a year.
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
When to call us in Dunn Street
Water gets into small cracks in the mastic and loosens it further. Windows facing the weather tend to go first.
Signs it’s time to call us include:
- A silicone bead on a sash window that spoils the look
- Draughts and rain around sash boxes
- Old sand mastic that has cracked, crumbled or fallen out
- Weathered mastic on the most exposed windows
If you live in an older home near Church of St Peter, the joint between an old wall and a newer frame is usually the first place rain gets in.
What your quote should include
- Who turns up on the day
- What preparation is included
- What the quote includes, VAT included or not
- What guarantee comes with the work
Landlord and commercial work in Dunn Street
Failed sealant is one of the commonest items on a check-out report, and it’s easy to sort out between tenants. Several properties can be quoted together.
Housing providers, facilities teams and property managers book us too in Dunn Street and across Medway. Several sites can go on one quote, and we are fully insured.
Keeping the joints in good condition
A little care helps the new joints last. Our advice:
- Get any rot dealt with first
- Check the mastic when you check the paintwork
- Plan mastic work ahead of painting
- Don’t paint over the new mastic
Look at the mastic when you look over the windows. Small cracks are easier to deal with early.
Fine cracks show the mastic is starting to fail. Renewing it then is simpler than waiting until it falls out.
How the job changes by surface
Period and listed homes
Many older homes were built with sand mastic round the windows. If your home is listed, ask your local planning authority about consent.
Stone surrounds
The stone is treated with care while raking out the old mastic.
What we do, step by step
There is not much for you to do on the day. Point us to the joints and we’ll get on with it. The job generally takes anything from a few hours to a full day, depending on how many windows, including the tidy-up. Somewhere like Dunn Street 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.
- We check each window surround and the condition of the joint.
- We rake out the old mastic and clean the joint.
- We fill deep gaps so the new mastic is not too thick.
- We point the joint with sand mastic by hand.
- The finish is dressed neatly.
Before we arrive
- Let us know about stairs, lifts or work at height
- Clear items away from the joints we’re working on
- Mention any sign-in or site rules at work premises
Get a quote
Every job is quoted individually. Simply call 0345 464 0079 or drop us an email and describe the job, and photos are welcome.
Read more
Common questions in Dunn Street
Do you cover smaller places like Dunn Street?
Yes, smaller places are covered as well as towns. We work across London and the South East. Just mention lanes, gates or anything else about the route when you book.
I let a flat near Rainham (Kent) station. Can you help?
Yes. We work for letting agents and landlords as well as homeowners. Just call 0345 464 0079 or drop us an email with the address and what needs doing, and we’ll send you a clear quote.
Do I have to be there?
We need access to the joints, so we’ll agree that with you when we book. For inside work, that normally means someone being in.
How do I get a quote for sand mastic in Dunn Street?
Size, access and the old material all affect the cost. Ask us for a quote.
Can I do it myself?
It depends on the job. High-level, external movement and fire-rated joints are professional jobs.
What’s sand mastic made of?
A traditional pointing material made from sand and a linseed-oil-based binder, used between timber frames and stone or brick.
Is it possible to paint over sand mastic?
It’s traditionally left unpainted, which is what traditional guidance recommends. Talk to us before any painting near it.
Is the work guaranteed?
Every job comes with our one-year guarantee.
Dunn Street homes and the weather
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.
Rented homes near Rainham (Kent) station change hands often, and any sash windows need sound mastic to keep draughts and rain out. Schools such as Swingate Primary School are buildings too, and the mastic around its windows and doors needs looking after like any other building’s.
Dunn Street is about 3 miles south-east of Chatham, in Medway. Whether you’re in the middle of Dunn Street or further out, sand mastic is available for homes and businesses alike. Dunn Street is one of 68 towns and villages in Medway where we work. Our Chelmsford page covers work nearby, about 29 miles away.
Postcode districts we cover here for sand mastic: ME7. Other places close to Dunn Street include Lidsing (1 mile north-west), Bredhurst (1 mile north-east), Scragged Oak (1 mile south-east), Kemsley Street (1 mile north-east) and Lower Cox Street (1 mile south-east). Further out, we also cover Gillingham (3 miles north), Chatham (3 miles north-west), Rochester (5 miles north-west), Rainham (3 miles north-east), Strood (6 miles north-west) and Luton (3 miles north-west).
Around Dunn Street
Around Dunn Street, our work takes us to homes and buildings near South Wood and The Harrow pub and the streets around them. For rail, the closest station is Rainham (Kent) station, roughly 3.3 miles north-east. Nearby you will also find KIMS hospital (2.8 miles south) and Allington Castle (3.4 miles south-west). Not far away are Boxley Hills and Burham Down.