Buckinghamshire · England
Sand mastic for sash & case windows in Waterside, Buckinghamshire
Sand mastic in Waterside from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Cement or filler used on old window joints that has cracked
- Crumbling sand mastic round a window
- Open joints round the window box
Leave it or put it right?
New mastic over crumbling mastic will not hold. Raking out and preparing the joint gives it a sound base so the new work lasts. Where a wall is exposed, as many are in small places like Waterside, wind-driven rain gets into any failed joint, and damp in older walls is slow to dry out.
What you pay reflects the work, not guesswork. That’s why we ask a few questions first and send you a clear quote before any work starts.
Why Waterside customers choose us
- Quality sealants from Arbo and Everbuild
- Every job guaranteed for a year
- Old sealant always removed completely
- Neat joints and a tidy finish
About our sand mastic in Waterside
Sand mastic suits most period window surrounds. Newer frames normally get a flexible sealant instead and we’ll explain which is best for yours. We work on tenement windows, timber door frames and brick reveals, and people most often call us about patchy fillers round a sash window and open joints round the window box.
Homes in small places like Waterside 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.
We stand behind the work with a one-year guarantee, so you are covered after we’ve gone.
- Location
- Waterside (HP5)
- Region
- Buckinghamshire
- Guarantee
- A year, on every job
- Quotes
- Quoted before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Places near Waterside
Other services in Waterside
Can I do it myself?
The biggest DIY mistake is sealing over old sealant. New silicone won’t bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
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.
Common questions in Waterside
I let a flat near Amersham station. Can you help?
Yes, we work for landlords and letting agents. You can ring 0345 464 0079 or email us with the address and a few details, and we will give you a fixed price before we start.
Do you cover smaller places like Waterside?
Yes. Waterside is within the area we cover, which takes in towns, villages and rural addresses. We work across London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Which is right for my windows, sand mastic or modern sealant?
For period timber windows in stone or brick, sand mastic is often the better fit. Modern frames normally suit a flexible sealant.
Do you guarantee sand mastic work?
Our 12-month guarantee applies to all our work.
Are you insured?
Yes. We are fully insured.
Where is Mr Mastic based?
We are based in Crawley, and we work across South East England, London and Scotland.
Can old silicone round a sash window be swapped for sand mastic?
Often, yes. Once the silicone is out and the joint prepared, sand mastic is applied by hand.
Can I choose the sealant colour?
We’ll suggest a colour to suit the surroundings, from white and clear to greys and other shades. The choice depends on the product the joint needs.
Aftercare tips
So the new joints stay in good condition:
- Check with your local planning authority if your home is listed
- Check the mastic when you check the paintwork
- Take care around the mastic when scraping paint
- Sort the mastic before the decorators arrive
Keep gutters and sills clear so water runs away from the surround. Water sitting against the mastic shortens its life.
Renewing mastic before redecorating saves doing it twice. Paint over cracked mastic only covers it up.
How the job changes by surface
Brick reveals
Sand mastic is also used where timber frames meet brick. It gives a traditional finish.
Timber door frames
Doors face weather and wear and the mastic can crack early. We rake it out and renew it.
Work for landlords, hotels and businesses
From a single let to a portfolio, the work is the same standard: the old material taken out, careful preparation and a 12-month guarantee.
If you manage several properties in or around Waterside, jobs at different addresses can be quoted together. Send us the addresses and the work at each, and pictures by email help.
How it works
Most of a good job is in the preparation, so that’s where we spend the time. Joints are cleaned back and dried before anything new goes in. In total, it generally takes a few hours per window, depending on the condition of the joints. In a small place like Waterside, access is generally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We look at the surrounds with you and agree the joints to renew.
- We remove the old, loose mastic.
- Deep gaps are packed so the mastic sits at the right depth.
- We apply the mastic by hand and shape it.
- The surface is finished to suit the stone or brick.
Getting ready for the visit
- Where the joints are inside, avoid wetting them before we arrive
- Keep children and pets away from the work area
- Tell us about any water getting in
Ask for a quote
Call for a quick quote, or send an email if you’d rather. Describe what needs sealing and we’ll talk you through the work.
Read more
Frames and glazing around Waterside
With historic houses such as Chenies Manor House (about 3.4 miles south-east) nearby, there’s older building stock in the area around Waterside as well as newer homes. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that’s traditional sand mastic. 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.
For an older house near a landmark such as Christ Church, the joint between an old wall and a newer frame is usually the first place rain gets in. If you let a flat or house near Amersham station, any sash windows need sound mastic to keep draughts and rain out.
Waterside is about 1 mile south of Chesham, in Buckinghamshire. For sand mastic in and around Waterside, please phone 0345 464 0079 or drop us an email for a quick quote. We’re based in Crawley and cover Buckinghamshire. Our Buckinghamshire coverage runs to 263 places, Waterside among them. Our Reading page covers work nearby (24 miles or so).
Every address in HP5 is within our area for sand mastic, from the main roads to the quietest streets. We cover properties on Moor Road, Trapp's Lane and Hodds Wood Road and the roads around them. Other places close to Waterside include Chesham Bois (1 mile south), Amersham (1 mile south), Amersham on the Hill (2 miles south), Hyde Heath (2 miles west) and Woodrow (3 miles south-west). Within a short drive, we also cover Aylesbury (12 miles north-west), High Wycombe (8 miles south-west), Marlow (11 miles south-west), Beaconsfield (6 miles south), Chalfont St Peter (7 miles south) and Elmhurst (13 miles north-west).
Local landmarks in Waterside
Around Waterside, our work takes us to homes and buildings near The Pheasant pub, Chesham Grammar School and Home Tuition Service. Waterside’s nearest station is Amersham station, roughly 1.6 miles south of the centre. Other landmarks nearby include Amersham Hospital (2.5 miles south) and Hawridge Court (3.3 miles north). Green spaces nearby include Sands Bank.
Common problems we fix in Waterside
Some old mastic was never deep enough. Mastic that is too thin cracks and drops out so we make sure the new mastic is the right thickness.
Signs it’s time to call us include:
- Failed mastic on an exposed elevation
- Cement or filler used on old window joints that has cracked
- Open joints round the window box
- Cracked mastic round a front door frame
For site and facilities teams at buildings such as Waterside Primary Academy, larger buildings have plenty of frames, and the mastic around each one ages.
What to look for in a quote
- How much experience the applicator has
- Which sealant they’ll use, and why
- Whether they seal over old material or remove it
- How the joint is cleaned and prepared