Portsmouth · England
Sand mastic for sash & case windows in Landport, Portsmouth
Professional sand mastic in and around Landport, with old sealant always removed completely and a 12-month guarantee.
- Gaps between timber frames and stone or brick
- Cracked mastic round a front door frame
- Draughty sash windows at the surround
Sand mastic in Landport, done properly
If your home is listed or in a conservation area, check with your local planning authority if consent is needed before window work. Like-for-like sand mastic is often the preferred finish. We’re often asked to deal with wind and rain getting in round a sash window and a silicone bead on a sash window that spoils the look, across period & listed homes, timber door frames and stone surrounds.
Houses in smaller places like Landport can stand more in the open than those in a built-up town. The mastic around frames on those walls tends to age faster.
All of our work is guaranteed for twelve months.
- Place
- Landport (PO1, PO2, PO5)
- Wider area
- Portsmouth
- Cover
- One year on every job
- Price
- A clear price before work begins
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
What happens on the day
A visit follows a simple pattern: we check the joints, mask and protect the surrounding surfaces, do the work and clear up. Most jobs take a few hours for a single window, longer for several. In a smaller place like Landport, parking is seldom the issue; lanes, gates and long drives are worth mentioning. If the job is outside, tell us about side access and how high the joints are.
- Each surround is checked first.
- We rake out the old mastic and clean the joint.
- Large voids are packed out.
- We point the joint with sand mastic by hand.
- We finish the mastic to a tidy line.
Before we arrive
- Mention any tricky access
- On commercial sites, let us know about site rules
- For indoor joints, keep the area dry beforehand if you can
Ask for a quote
Every job is quoted individually, so the first step is telling us about yours. Simply call 0345 464 0079 or send us an email and describe the job, and photos are welcome.
Advice
How to look after the new joints
No joint lasts for ever, but care makes a real difference. A few tips:
- Avoid heavy scraping on the mastic joint
- Avoid patching sand mastic with silicone
- Make sure water runs off the sill
- Check the mastic when you check the paintwork
Avoid painting over the new mastic, which is the traditional advice. If you are redecorating, ask us first.
Fine cracks show the mastic is starting to fail. Renewing it then is simpler than waiting until it falls out.
Why deal with it now?
If you’re redecorating, renew the mastic first. Painting over failed mastic doesn’t seal it, and the new mastic is traditionally left unpainted. In a smaller place like Landport, wherever a wall is exposed, a failed outside joint is a real source of damp. Inside, a split seal lets water into floors and panels just as it would anywhere.
There are no prices on our website, because the cost depends so much on the job itself. Call for a quick quote and we will talk you through it.
Why Landport customers choose us
- Old sealant always removed completely
- Anti-fungal sanitary silicone in wet areas
- Homes, businesses and hotels
- Tidy, careful work
See our cost guide and our reviews.
Other services in Landport
What sealant work can’t fix
Honest advice matters more to us than a booking, so here’s what new sealant will not do:
- Whether work needs listed building consent
- Rotten sashes, sills or window boxes (a joiner’s job)
- Sashes that rattle, stick or will not open
If you’re not sure, just ring 0345 464 0079 or email us and we’ll give you a straight answer.
Where we work in Landport
- Stone surrounds
- Brick reveals
- Timber door frames
- Sash and case windows
- Tenement windows
- Period & listed homes
FAQs for Landport
Is Landport within the area you cover?
Yes. Landport is within the area we cover, which takes in towns, villages and rural addresses. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Can you help a landlord with a rental near Portsmouth & Southsea station?
Yes, rental work is part of what we do. Just ring 0345 464 0079 or send us an email and tell us about the property, and we’ll send you a clear quote.
How long does sand mastic take?
It depends on the size of the job, but most jobs take a few hours for a single window, longer for several. We will tell you when we quote.
Is it worth trying it myself?
Some simple jobs can be done by a careful DIYer. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Do you take out the old sealant first?
Always. Sealing over the old bead is the commonest cause of early failure, and it’s something we never do.
Can sand mastic be painted?
Sand mastic is normally left unpainted, as guidance on traditional windows advises. Talk to us before any painting near it.
What do you put in the joint?
The product depends on the job: sanitary silicone where it gets wet, and sealants suited to movement or weather elsewhere. Brands we use include Arbo and Everbuild.
Is consent needed for window work on a listed home?
Checking first is sensible. Your local planning authority can say if consent is needed for work on a listed home or in a conservation area.
Frames and glazing around Landport
Landport 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 is hard on the mastic around older windows and doors, especially on the side facing the sea. Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Letting a property close to Portsmouth & Southsea station? Then older sash windows in a rental need their mastic kept sound to keep the weather out. Schools such as Ark Dickens Primary Academy are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages.
Landport is about 1 mile south-west of Portsmouth, in Portsmouth. Landport gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a 12-month guarantee. Across Portsmouth, we cover 19 places, Landport among them.
Work in PO1, PO2 and PO5 works the same way as everywhere else we cover. Local streets include Lake Road, Watts Road and Alfred Road, and we cover them all. We also cover Portsmouth (1 mile north-east), Fratton (1 mile east), Rudmore (1 mile north), Kingston (1 mile east) and North End (1 mile north). Within a short drive, we also cover Wymering (3 miles north), Paulsgrove (3 miles north), Cosham (3 miles north), Drayton (3 miles north-east) and Farlington (4 miles north-east).
Local landmarks in Landport
In Landport, that means homes and buildings near The Painters Arms, St Edmund's Catholic School and Alexandra Park. There’s a railway station in Landport itself: Portsmouth & Southsea station. A little further out are Royal Portsmouth Hospital (under half a mile south-west) and Charles Dickens Birthplace Museum (within half a mile north). For a walk, there’s Milton Locks and Portsdown Hill.
Should I try it myself first?
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and does not move well, and getting the depth right matters as much as the look.
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Quotes for sand mastic in Landport
Jobs vary more than people expect. The main factors:
- How much old sealant there is and how hard it is to remove
- Mould in or behind the old joints
- How many rooms, windows or areas are involved
- When we can work, for business premises
Instead of a standard rate, we price the job in front of us: the amount of work, the old material and the access. The price is agreed before we begin.
Helping us quote
Before you ask for a quote, have a think about:
- The rough size of the job
- Access, such as stairs, a lift or height
- Pictures of the joints, sent by email
- Whether it’s a home or a business
To get a quote, ring 0345 464 0079 or email us with the location and a short description of the problem. You will have a clear quote before we start.
Signs you need sand mastic in Landport
Over the years, sand mastic weathers. It dries out, cracks and loses its grip from the frame or the masonry.
The problems people usually mention when they call are:
- Draughts and rain around sash boxes
- Cracked mastic round a front door frame
- Failed mastic on an exposed elevation
- Window mastic to renew ahead of painting
Homes close to Church of All Saints include some older properties, and replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint.
What your quote should include
- Whether all the old sealant comes out first
- What the cure time is
- How the colour is chosen
- Which sealant they’ll use, and why