West Sussex · England
Sand Mastic in Highleigh
Professional sand mastic in and around Highleigh, with every bit of old sealant taken out first and a 12-month guarantee.
- Weathered mastic on the most exposed windows
- Crumbling sand mastic round a window
- Mastic round period door frames that has failed
About our sand mastic in Highleigh
Silicone on a period window often looks wrong 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. Typical jobs include cement or filler used on old window joints that has cracked and mastic that needs renewing before redecorating, on timber door frames, sash and case windows and stone surrounds.
Outdoor sealant needs dry, clean surfaces, so work on frames around Highleigh is planned for dry weather. Let us know about access to all the frames, upstairs ones included.
Each job carries a 12-month guarantee.
- Location
- Highleigh (PO20)
- Region
- West Sussex
- Guarantee
- 12 months on all our work
- Price
- A clear price before we start
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
When to call us in Highleigh
Shallow joints are a common cause. Mastic that’s too thin cracks and drops out, which is why we pack deep voids first and get the depth right.
Look out for these signs:
- Gaps round a timber door in stone or brick
- Window mastic to renew ahead of painting
- Patchy fillers round a sash window
- Old sand mastic that has cracked, crumbled or fallen out
In the older streets around St Mary Our Lady Sidlesham, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
What to look for in a quote
- Who does the work, and how experienced they are
- What happens if they find a problem under the old sealant
- What insurance they hold
- What the quote includes, VAT included or not
Also near Highleigh
More services for Highleigh
Why act early in Highleigh
An open joint round the frame lets weather in. Water can get to the frame and the masonry, so dealing with it now protects both. Where a wall is exposed, as many are in small places like Highleigh, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
The cost reflects the work involved, not a rough estimate. That is why we ask a few questions first and send you a clear quote before work begins.
Why book with us
- An ARBOMaster approved applicator
- Anti-fungal sanitary silicone in wet areas
- Homes, businesses and hotels
- Every job guaranteed for a year
Take a look at how sealant jobs are priced and our reviews.
Can I do it myself?
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
Overfilling a joint is a classic DIY mistake. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
What affects the cost of sand mastic
There’s no set price list, because no two jobs are the same. The quote depends on:
- When we can work, for business premises
- Mould in or behind the old joints
- How many rooms, windows or areas are involved
- Whether old sealant or filler has to be cut out
What it costs depends on how much there is to do, how much old material has to come out and access to the work. You will have a clear quote before any work starts.
What we need to know
The more you tell us, the more accurate the quote. When you get in contact, it helps to mention:
- Photos by email, if that is easy
- Any access issues, like height or stairs
- The problem you’ve noticed
- Where the property is
For a quote, call 0345 464 0079 or drop us an email and tell us where the job is and what the problem looks like. You will have a clear quote before we start.
The process
There is not much for you to do on the day. Point us to the joints and we will get on with it. The work itself takes a few hours for a single window, longer for several, including the tidy-up. Somewhere like Highleigh needs a little journey planning: let us know about lanes, gates and parking. We bring what the job needs, so it can be finished in one trip where possible.
- We look at the surrounds with you and agree the joints to renew.
- Old mastic and any loose material are raked out.
- We pack any deep voids first.
- The sand mastic is mixed and pressed into the joint by hand.
- The surface is finished to suit the stone or brick.
Preparing for the visit
- Mention if the joints have been sealed before
- Clear items away from the joints we are working on
- Tell us about any water getting in
Get a quote
Call for a quick quote, or send an email if you’d rather. Tell us about the joints that need doing and we will talk you through the work.
Read more
Keeping the joints in good condition
How long the joints last depends on use and care. Here’s what we suggest:
- Ask a joiner to look at soft timber first
- Don’t paint over the new mastic
- Ask the planning authority about consent for listed or conservation-area homes
- Renew mastic before redecorating the windows
Don’t run silicone over the new mastic. If anything cracks, get it looked at rather than patching it.
Sound mastic protects the frame. Once it fails, water can sit against the timber, which can lead to rot.
Windows and doors in Highleigh
Highleigh is close to the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. That’s hard on the mastic around older windows and doors, especially on the side facing the sea. Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
If you let a flat or house near Chichester station, cracked sand mastic around sash windows lets in the draughts tenants complain about. If you look after a building such as Sidlesham Primary School, larger buildings have plenty of frames, and the mastic around each one ages.
Highleigh is about 3 miles north of Selsey, in West Sussex. Highleigh gets the same service as everywhere we cover: the old material taken out, joints prepared properly and a 12-month guarantee. Our area takes in 371 places across West Sussex. There’s also a page for Portsmouth, roughly 12 miles from Highleigh.
We cover every part of the PO20 postcode area for sand mastic. We cover properties on Critchel's Lane, Highleigh Road and Green Lane and the roads around them. Neighbouring places we cover for sand mastic include Almodington (1 mile west), Birdham (2 miles north-west), Somerley (2 miles west), Earnley (2 miles west) and Shipton Green (3 miles north-west). Within a short drive, we also cover Bognor Regis (5 miles east), Chichester (4 miles north), Selsey (3 miles south), Littlehampton (12 miles east), Emsworth (8 miles north-west) and Rustington (13 miles east).
Local landmarks in Highleigh
For rail, the closest station is Chichester station, about 3.9 miles north of the centre. Nearby you’ll also find Chichester Castle (4.5 miles north) and Selsey Lifeboat Museum (3.5 miles south). Open spaces near Highleigh include Pilsey Island.
What we can’t put right
Some problems need a builder, plumber or other trade rather than us:
- Sash cords, weights and draught-proofing of the sashes
- Crumbling stone or brickwork round the window
- Decisions on consent for listed homes
If in doubt, phone 0345 464 0079 or email us and we will say what we think.
Joints and surfaces we work on
- Brick reveals
- Period & listed homes
- Sash and case windows
- Tenement windows
- Timber door frames
- Stone surrounds
Questions from Highleigh
Can you help a landlord with a rental near Chichester station?
Yes, rental work is part of what we do. You can phone 0345 464 0079 or drop us an email with the address and a few details, and we will give you a fixed price before we start.
Does the coastal weather in Highleigh affect outside sealant?
Near the sea, outside joints face more wind, rain and salt than they would inland, so preparation and the right sealant matter all the more. It’s worth checking the walls that face the sea first.
Is it OK to seal over old sealant?
No, because it fails. We remove every bit of old sealant first.
Is it possible to take out silicone and use sand mastic instead?
In most cases. We remove the silicone and clean the joint before the sand mastic goes in.
Where is Mr Mastic based?
We work from Crawley. We cover Highleigh and the rest of West Sussex, along with the rest of our area.
What exactly is sand mastic?
It’s a mix of sand and a linseed-oil-based binder. It’s applied by hand and finished to sit neatly against the masonry.
Does someone need to be in?
For indoor joints, yes, someone needs to let us in. Once we have agreed the job, you do not need to watch us work.
Do you have insurance?
Yes. We are fully insured, with over 20 years’ experience in sealant work.