West Sussex · England
Sand mastic for sash & case windows in Compton, West Sussex
Sand mastic across Compton and nearby, with every bit of old sealant taken out first and a 12-month guarantee.
- Gaps round a timber door in stone or brick
- Mastic dropping out of the joint
- Cement or filler used on old window joints that has cracked
Different surfaces, different methods
Stone surrounds
Old stone surrounds are often uneven, so the gap isn’t the same all the way round. We shape it by hand to follow the stone.
Sash and case windows
On a sash window, the mastic joint shows on the outside so we finish it carefully.
How we handle sand mastic in Compton
Silicone on a period window often looks wrong and isn’t always the right material. Sand mastic gives a finish that matches the age of the house, and we can replace one with the other. If you are dealing with mastic that needs renewing before redecorating and mastic round period door frames that has failed, we can help, on tenement windows, brick reveals and sash and case windows alike.
Mastic can only go onto a dry, clean joint, so window work in Compton is booked around the forecast. Let us know about access to all the frames, upstairs ones included.
The work is covered for a year after we finish. If anything isn’t right with it, ring 0345 464 0079 or send us an email.
- Where
- Compton (PO18)
- Region
- West Sussex
- Cover
- A year, on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Honest limits
We will not take on work that will not last, so here’s what sealant cannot put right:
- Decisions on consent for listed homes
- Sash cords, weights and draught-proofing of the sashes
- Damaged stone surrounds
If in doubt, ring 0345 464 0079 or send us an email and we’ll say what we think.
What we seal
- Tenement windows
- Timber door frames
- Stone surrounds
- Sash and case windows
- Period & listed homes
- Brick reveals
What we’re called out for in Compton
Sand mastic slowly weathers. It dries out, cracks and loses its grip from the frame or the masonry.
Most people get in touch when they notice one of these:
- Old sand mastic that has cracked, crumbled or fallen out
- A silicone bead on a sash window that spoils the look
- Tired mastic found when preparing windows for paint
- Gaps where the frame meets the masonry
If you let a flat or house near Rowlands Castle station, any sash windows need sound mastic to keep draughts and rain out.
What your quote should include
- Whether they’re fully insured
- How long to leave it before use
- Which sealant they’ll use, and why
- Whether they seal over old material or remove it
Can I do it myself?
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
If you’ve already had a go yourself, that’s fine. We remove it and do the joint properly, so tell us about it when you ask for a quote.
Aftercare tips
To keep the joints looking good and working properly:
- Clear gutters so water doesn’t pour onto the windows
- Plan mastic work ahead of painting
- Ask the planning authority about consent for listed or conservation-area homes
- Get any rot dealt with first
Leave the new mastic unpainted, which is the traditional advice. If you are redecorating, ask us first.
Crumbling mastic lets rain into the joint. That water can reach the timber frame and the wall, so renewing it early is worth it.
Work for landlords, hotels and businesses
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.
Mouldy or split sealant often shows up at the end of a tenancy. Several properties can go on one quote.
Places near Compton
More services for Compton
Sand mastic in Compton: local notes
Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. Historic houses like Uppark (about 1.8 miles north) are a reminder that the area around Compton has older buildings as well as new. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window.
For an older house near a landmark such as The Parish Church of St Mary, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. For site and facilities teams at buildings such as Compton and Up Marden CofE Primary School, the mastic around its windows and doors needs looking after like any other building’s.
Compton is about 5 miles east of Horndean, in West Sussex. Anywhere in PO18, we can carry out sand mastic at your property. Across West Sussex, we cover 371 places, Compton among them. For nearby work, see our Portsmouth page (11 miles or so).
Every address in PO18 is covered for sand mastic, from the main roads to the quietest streets. That includes homes and businesses on Church Lane and School Lane and the roads around them. Neighbouring places we cover for sand mastic include East Marden (2 miles east), South Harting (3 miles north), East Harting (3 miles north-east), Chilgrove (4 miles east) and Elsted (4 miles north-east). We also work in nearby towns such as Bognor Regis (13 miles south-east), Chichester (8 miles south-east), Selsey (14 miles south), Emsworth (6 miles south), Portfield (9 miles south-east) and Yapton (15 miles south-east).
Local landmarks in Compton
We work in homes and buildings around The Coach And Horses Public House and the streets around them. The nearest railway station is Rowlands Castle station, roughly 3.6 miles south-west. Nearby you will also find Petersfield Community Hospital (5.7 miles north) and Clanfield Earthwork (4 miles west). For a walk, there’s Kingley Vale National Nature Reserve and Compton Down.
How the visit works
Most of a good job is in the preparation, so that is where we spend the time. Joints are cleaned back and dried before anything new goes in. All told, the work takes anything from a few hours to a full day, depending on how many windows. In a small place like Compton, access is generally the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- Each surround is checked first.
- The joint is raked out and cleaned.
- We fill deep gaps so the new mastic isn’t too thick.
- New sand mastic is applied and shaped by hand.
- We finish the mastic to a tidy line.
Preparing for the visit
- Move anything stored near the joints
- Mention if the joints have been sealed before
- Let us know if you’ve seen damp or leaks
Ask for a quote
Need a quote? Please phone 0345 464 0079 or email us and tell us about the job. We’ll explain what we’d do and give you a clear quote before we start.
Related advice
FAQs for Compton
I let a flat near Rowlands Castle station. Can you help?
Yes. We work for landlords and letting agents as well as householders. You can phone 0345 464 0079 or email us with the details for a clear quote.
Is Compton in your area for sand mastic?
Yes. We work across London and the South East, and Compton is part of that. Just call 0345 464 0079 or email us with a few details of the job.
How long does sand mastic take?
A typical job takes a few hours for a single window, longer for several. We’ll confirm how long when we quote.
Is the work guaranteed?
Our 12-month guarantee applies on every job.
Can sand mastic be painted?
The usual advice is to leave sand mastic unpainted. If you’re redecorating the window, ask us first and we will talk you through it.
Should I try DIY first?
It depends on the job. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional, while a short indoor joint may be within reach.
Is there any odour?
That depends on the sealant. Some smell for a while, some hardly at all, and any smell fades as they cure.
Should I use sand mastic or silicone?
We’ll help you decide. Sand mastic suits many period homes, and modern sealants suit newer frames.