Hampshire · England
Sand mastic for sash & case windows in Northney, Hampshire
Professional sand mastic in and around Northney, with old sealant always removed completely and a one-year guarantee.
- Mastic worn away on windows facing the weather
- Crumbling sand mastic round a window
- Gaps where the frame meets the masonry
Sand mastic in Northney
Sand mastic is the traditional way to point the gap between a timber window frame and the stone or brick around it. It’s a mix of sand and a linseed-oil-based binder and built up by hand. On period homes, it looks right where silicone wouldn’t. Typical jobs include modern sealant on a period surround and mastic dropping out of the joint, across timber door frames, sash and case windows and brick reveals.
Homes in small places like Northney often stand in the open, with little to shelter their windows from wind and rain. Exposed frames and sills lose their mastic sooner than sheltered ones.
Every job comes with our 12-month guarantee.
- Location
- Northney (PO11)
- Wider area
- Hampshire
- Cover
- 12 months on all our work
- Price
- A clear price before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Why it’s worth doing now in Northney
New sash windows are a major, costly change, and in listed buildings it may need consent. If the frames are sound, renewing the mastic deals with gaps and draughts at the surround. Where a wall is exposed, as many are in small places like Northney, 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 a rough estimate. That’s why we ask a few questions first and send you a clear quote before any work starts.
Why us?
- ARBOMaster approved applicator
- Anti-fungal sanitary silicone in wet areas
- Quality sealants from Arbo and Everbuild
- Rated 4.9 stars on Google
Take a look at our cost guide and what customers say.
DIY sealant or a professional job?
The biggest DIY mistake is sealing over old sealant. Silicone doesn’t stick to old silicone, so it peels away and traps moisture behind it. Everything old must be removed first.
The difference is mostly in the preparation and the product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions, then guaranteed for a year.
How the job changes by surface
Timber door frames
Sand mastic is used round timber door frames too. We renew it the same way as on windows.
Period and listed homes
A traditional finish suits a period property.
How we quote for sand mastic
Your quote is based on your job. We look at:
- How many areas need sealing
- Whether old sealant or filler has to be cut out
- The size of the job
- The type of sealant required
A few things move the cost up or down: how much old sealant there is and how stubborn it is, any mould to treat, and whether the work is at height. We take all of that into account in your quote.
Helping us quote
To make quoting easier, let us know:
- The address or postcode of the job
- Access, such as stairs, a lift or height
- The problem you’ve noticed
- The rough size of the job
For sand mastic in Northney, phone 0345 464 0079 or send us an email. Tell us what the problem is and where, and you will get a clear quote before any work starts.
What sand mastic looks like in Northney
Northney 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. Both are hard on the mastic around older windows and doors, which can dry out and crack sooner where a building faces the weather. Historic houses like Warblington Castle (about 1.1 miles north) are a reminder that the area around Northney has older buildings as well as new. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that’s traditional sand mastic.
Schools such as Warblington School are buildings too, and the mastic around its windows and doors needs looking after like any other building’s. Homes close to Church of St Peter include some older properties, and the joint between an old wall and a newer frame is normally the first place rain gets in. Rented homes near Warblington station change hands often, and any sash windows need sound mastic to keep draughts and rain out.
Northney is about 3 miles south-east of Havant, in Hampshire. Every kind of property in Northney is covered for sand mastic, old or new, large or small. The work is guaranteed for a year. Our Hampshire coverage runs to 683 places, Northney among them.
Jobs for sand mastic in PO11 works the same way as everywhere else we cover. Whether your property is on Northney Lane, Spinnaker Grange and Northney Road or anywhere close by, our applicators can take on the job. Other places close to Northney include North Hayling (1 mile south), Warblington (1 mile north), Tye (1 mile south), Stoke (1 mile south-west) and Langstone (1 mile north-west). We also work in nearby towns such as Gosport (8 miles west), Havant (3 miles north-west), Fareham (10 miles west), Horndean (6 miles north), Waterlooville (5 miles north-west) and Petersfield (12 miles north).
Near you in Northney
In Northney, that means homes and buildings near Eames Farm and The Ship Inn. For rail, the closest station is Warblington station, roughly 1.7 miles north. Well-known places in the area include Havant Museum (1.7 miles north-west) and Havant War Memorial Hospital (2.1 miles north-west). Not far away are Hayling Billy.
Also near Northney
What else we do in Northney
When something else is needed
We won’t take on work that will not last, so here’s what sealant can’t put right:
- Whether work needs listed building consent
- Timber that has rotted
- Putty and glazing repairs
Not sure which it is? You can call 0345 464 0079 or send us an email and we’ll tell you honestly.
What we seal
- Sash and case windows
- Timber door frames
- Period & listed homes
- Tenement windows
- Stone surrounds
- Brick reveals
What happens on the day
Every visit runs the same way: we look at the joints together, protect the area around them, carry out the job and clear up. Most jobs take a few hours for a single window, longer for several. In a small place like Northney, 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.
- We point the joint with sand mastic by hand.
- The finish is dressed neatly.
Before we arrive
- Let us know about earlier repairs to the joints
- Keep children and pets away from the work area
- Let us know if you’ve seen damp or leaks
Ask for a quote
Getting a quote is simple: let us know the job and the location, and roughly how big it is. Photos by email help us understand the job, and we will come back to you with a quote.
Read more
Questions from Northney
Is sand mastic in a coastal place like Northney any different?
Coastal weather is harder on outside sealant: there’s more wind-driven rain and, closer to the shore, salt in the air. The right product, a clean joint and the right depth all help it cope.
I let a flat near Warblington station. Can you help?
Yes, we work for landlords and letting agents. Just ring 0345 464 0079 or send us an email and tell us about the property, and we will give you a clear price.
Can sand mastic be painted?
It’s traditionally left unpainted, which is what traditional guidance recommends. Talk to us before any painting near it.
Will it make a mess?
Very little: the area around the joints is protected first, and we tidy up before we go.
What guarantee comes with the work?
Our one-year guarantee covers every job, sand mastic included.
Do the sealants smell?
Possibly a little. It fades as the sealant cures.
Can old silicone round a sash window be swapped for sand mastic?
Generally, yes. Once the silicone is out and the joint prepared, sand mastic is applied by hand.
Do you remove the old sealant?
Yes. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Aftercare tips
Simple care keeps the joints in good condition. We recommend:
- Avoid patching sand mastic with silicone
- Clear gutters so water does not pour onto the windows
- Take care around the mastic when scraping paint
- Ask us before painting near the mastic
Look at the mastic when you look over the windows. Catching cracks early keeps repairs small.
Fine cracks show the mastic is starting to fail. Renewing it then is simpler than waiting until it falls out.