West Sussex · England
Sand mastic for sash & case windows in Southwick, West Sussex
Sand mastic for Southwick, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Gaps round a timber door in stone or brick
- Gaps between timber frames and stone or brick
- Old sand mastic that has cracked, crumbled or fallen out
What sealant work cannot fix
It helps to know what we can’t do too:
- Putty and glazing repairs
- Decayed frames that need repair
- Sash cords, weights and draught-proofing of the sashes
Not sure which it is? You can call 0345 464 0079 or email us and we will tell you honestly.
Surfaces we seal
- Sash and case windows
- Tenement windows
- Timber door frames
- Period & listed homes
- Stone surrounds
- Brick reveals
How we handle sand mastic in Southwick
On many period windows, sand mastic looks right and suits the building. On modern frames we’d normally use a flexible sealant and we will explain which is best for yours. We work on tenement windows, period & listed homes and sash and case windows, and common reasons people get in touch are mastic that needs renewing before redecorating and crumbling sand mastic round a window.
Around Southwick, conservatories, garden rooms and patio doors are often part of the house. Those joints need the same attention as the main windows, and any older timber or sash windows need a sealant that suits them.
A one-year guarantee comes with the work, just as it does everywhere we cover.
- Place
- Southwick (BN42, BN41, BN43)
- Wider area
- West Sussex
- Cover
- A year, on every job
- Quotes
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
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 suits the building and blends with the stone or brick. In an older home around Southwick, damp from a failed joint can get into timber and plaster, and that is a much bigger job than renewing the sealant.
A few things move the cost up or down: the old material and how easily it comes out, any mould to treat, and whether we need extra access for height. We take all of that into account in your quote.
What you get with us
- 4.9 on Google from 180+ five-star reviews
- We leave the area clean and tidy
- Quality sealants from Arbo and Everbuild
- Anti-fungal sanitary silicone in wet areas
Take a look at our cost guide and customer reviews.
Signs you need sand mastic in Southwick
Over the years, sand mastic weathers. It hardens, cracks and starts to come away on the stone or timber.
It’s worth asking for a quote if you see:
- Patchy fillers round a sash window
- Gaps between timber frames and stone or brick
- Failed mastic on an exposed elevation
- Old sand mastic that has cracked, crumbled or fallen out
Letting a property close to Southwick station? Then older sash windows in a rental need their mastic kept sound to keep the weather out.
What your quote should include
- What the cure time is
- Who turns up on the day
- Which colour the sealant will be
- What happens if they find a problem under the old sealant
Looking after it afterwards
Aftercare is simple, and it makes a real difference:
- Plan mastic work ahead of painting
- Don’t run silicone over sand mastic
- Check the mastic when you check the paintwork
- Take care around the mastic when scraping paint
Make sure water drains away from the window surround. Constant wetting wears the mastic faster.
Fine cracks show the mastic is starting to fail. Renewing it then is simpler than waiting until it falls out.
How the visit works
A visit follows a simple pattern: we look at the joints together, mask and protect the surrounding surfaces, do the work and tidy away. Most jobs take a few hours for a single window, longer for several. A visit to Southwick is planned like any other: the time, the access and where to park are agreed in advance. Outdoor jobs depend on a dry day, since sealant needs a dry surface.
- First we agree which joints need doing.
- 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.
- We dress the finish so it sits neatly against the masonry.
Before we arrive
- Clear the area around the work
- Plan for the work area to be out of bounds to pets and children
- On commercial sites, let us know about site rules
How to get a quote
If you’re in Southwick and need sand mastic, call 0345 464 0079 or drop us an email. Tell us what the problem is and where, and we’ll agree the price before any work begins.
Advice
Common questions in Southwick
I let a flat near Southwick station. Can you help?
Yes, landlords and agents are among the people we work for. Just ring 0345 464 0079 or email us with the address and what needs doing, and we’ll give you a clear price.
Will you come out to Southwick?
Yes, we do. We work across London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
What sealant do you use?
The product depends on the job: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. Brands we use include Arbo and Everbuild.
Can you quote for more than one area?
Yes. Tell us about everything you’d like done and we will quote it together.
Are you fully insured?
Yes. We are fully insured, with over 20 years’ experience in sealant work.
Will the old sealant be removed?
Always. Sealing over the old bead is the commonest cause of early failure, and it’s something we never do.
Should I try DIY first?
You can, for simple jobs. The key is preparation: remove all the old material and work on a clean, dry joint. We can always put it right if it fails.
Can I paint the new mastic?
Sand mastic is normally left unpainted, which is what traditional guidance recommends. Talk to us before any painting near it.
Southwick homes and the weather
Southwick is within about 1 mile of the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. That is hard on the mastic around older windows and doors, especially on the side facing the sea. With historic houses such as Portslade Manor (about 0.8 miles north-east) nearby, there’s older building stock in the area around Southwick 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 Eastbrook Primary Academy? Then the mastic around its windows and doors needs looking after like any other building’s. In the older streets around St Michael and All Angels Church, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint.
Southwick is about 2 miles east of Shoreham-by-Sea, in West Sussex. We carry out sand mastic for homes and businesses in Southwick and the surrounding area, as part of our work across West Sussex. Across West Sussex, we cover 371 places, and Southwick is one of them.
All of BN42, BN41 and BN43 is covered for sand mastic, from the main roads to the quietest streets. You will find streets such as Station Road, Roman Crescent and Southwick Street. You will find Southwick on the A259 and A270, which makes it straightforward to reach. We also cover the places around Southwick: Kingston by Sea (1 mile north-west), Portslade (1 mile north-east), Shoreham-by-Sea (2 miles west), Hangleton (2 miles north-east) and Old Shoreham (2 miles west). We also work in nearby towns such as Worthing (7 miles west), Haywards Heath (13 miles north-east), Burgess Hill (10 miles north-east), Littlehampton (13 miles west), Lancing (4 miles west) and Rustington (12 miles west).
Around Southwick
We work in homes and buildings around Shoreham Academy, Benfield Hill and The Ship Inn and the streets around them. There’s a railway station in Southwick itself: Southwick station. A little further out are Southlands Hospital (1 mile west) and Churchill Square (4 miles east). The countryside around Southwick includes Shoreham Beach and Thundersbarrow Hill.
DIY versus a professional finish
If you’re set on DIY, put the effort into preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it fails, we can still redo it.
The difference is mostly in the preparation and the product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions.
Landlords, agents and businesses in Southwick
In hotels, rooms out of use cost money, so we plan the work room by room around your bookings where we can. We’ve worked in hotels as well as homes and businesses.
We also work for property managers and facilities teams. Several sites can go on one quote, and we are fully insured for the work.