West Sussex · England
Window & door mastic in Thorney Island, West Sussex
Window mastic for Thorney Island, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Whistling draughts around closed windows
- Untidy mastic left by window fitters
- Sealant in the wrong colour for the frame
Window mastic in Thorney Island
If you can feel air around a shut window, the gap is often at the frame. A new joint stops the air getting through. If the draught is through the window seals instead, we will tell you. If you are dealing with mastic that has split away from the wall and old mastic that has gone black or come away, we can put it right, whatever the surface.
Outdoor sealant needs dry, clean surfaces, so work on frames around Thorney Island is planned for dry weather. Tell us about access to every side of the house, including upper-floor windows.
You get a one-year guarantee, the same in Thorney Island as everywhere else we work.
- Location
- Thorney Island (PO10)
- Wider area
- West Sussex
- Cover
- One year on every job
- Quote
- A clear quote up front
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
FAQs for Thorney Island
Can you help a landlord with a rental near Southbourne station?
Yes. We work for landlords and agents as well as householders. Just phone 0345 464 0079 or drop us an email with the address and what needs doing, and we will give you a clear price.
Does the coastal weather in Thorney Island 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.
Should I try DIY first?
That depends on the joint. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional.
How long before the joint can be used?
It depends on the product. We tell you how long to leave it before we go.
How do I get a quote for window mastic in Thorney Island?
Every job is different, so each one gets its own quote. For a quick quote, call 0345 464 0079 or email us with a short description of the job.
Where is Mr Mastic based?
We’re a Crawley-based firm, with over 20 years’ experience. Our area covers South East England, London and Scotland.
Can I add another job to the visit?
Yes, and it often makes sense. Combining jobs makes good use of the visit, so mention them when you ask for a quote.
Can you seal the gap between the frame and the plaster indoors?
Yes. The outside joint keeps the weather out, and the inside joint stops draughts and finishes the reveal. We do one or both.
Places near Thorney Island
More services for Thorney Island
Landlords, agents and businesses in Thorney Island
Hotels need rooms back in use, so the work can be planned room by room. 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.
Looking after it afterwards
Aftercare is simple, and it makes a real difference:
- Ventilate rooms so frames don’t stay wet inside
- Repaint timber before it’s bare
- Avoid blasting the frames with a pressure washer
- Don’t paint over the silicone
Keep the new mastic undisturbed while it cures, following the cure time we give you. Do not point a pressure washer at the joints.
Leaks generally show up in wet, windy weather, but sealant goes on best when frames and walls are dry. Sorting cracked mastic early means the joint is sound before the bad weather.
What affects the quote in Thorney Island
Jobs vary more than people expect. The main factors:
- How many areas need sealing
- Any mould that needs treating
- Access and height
- Any working-time requirements on site
What you pay reflects the work, not guesswork. That’s why we ask about the job first and agree the price before starting.
Helping us quote
There’s no need for technical detail. It helps if you can tell us:
- Pictures of the joints, sent by email
- What the problem is, such as mould, gaps, leaks or cracking
- The rough size of the job
- Any previous sealing or DIY work
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is, and add pictures by email if you can.
Frames and glazing around Thorney Island
Thorney Island 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 window and door frames, which can dry out and crack sooner where a building faces the weather. Historic houses like Warblington Castle (about 2.1 miles north-west) are a reminder that the area around Thorney Island has older buildings as well as new. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
If you let a flat or house near Southbourne station, sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. If you live in an older home near The Parish Church of St Nicholas, the joint between an old wall and a newer frame is normally the first place rain gets in.
Thorney Island is about 4 miles south-east of Havant, in West Sussex. Every kind of property in Thorney Island can book us for window mastic, old or new, large or small. Every job comes with our 12-month guarantee. We cover 371 towns and villages across West Sussex, from the larger towns to small villages. Portsmouth is on our list too, around 7 miles away.
Work in PO10 works the same way as everywhere else we cover. Streets in the area include Hunter Road, Emsworth Road and Spartan Close, all of which we cover. Neighbouring places we cover for window mastic include West Thorney (1 mile south-east), North Hayling (1 mile west), Tye (1 mile south-west), Northney (1 mile west) and Emsworth (2 miles north). Within a short drive, we also cover Bognor Regis (11 miles east), Chichester (7 miles east), Selsey (9 miles south-east), Portfield (7 miles east), Yapton (14 miles east) and East Wittering (5 miles south-east).
Around Thorney Island
Typical jobs here are in homes near Bourne Community College and Eames Farm. The nearest railway station is Southbourne station, about 1.8 miles north-east. Well-known places in the area include Havant War Memorial Hospital (3.2 miles north-west) and Emsworth Museum (1.6 miles north). Open spaces near Thorney Island include Nutborne Marshes.
Do you need window mastic in Thorney Island?
Timber windows bring their own problems. Mastic painted over many times cracks with the paint, and timber moves with moisture as well as temperature.
Look out for these signs:
- Black, perished sealant on frames
- Mastic that has split away from the wall
- Sealant in the wrong colour for the frame
- Cracked sealant at the sill ends
For site and facilities teams at buildings such as Thorney Island Community Primary School, the mastic around its windows and doors needs looking after like any other building’s.
What your quote should include
- How the surfaces are prepared before sealing
- How the colour is chosen
- What insurance they hold
- What the quote includes, VAT included or not
What we cannot put right
We won’t take on work that will not last, so these are the limits:
- Faulty window hardware
- Worn gaskets, brush seals or a door that has dropped
- A failed sealed unit that has misted up
If you’re not sure, just ring 0345 464 0079 or drop us an email and we will give you a straight answer.
What we seal
- Aluminium frames
- Window sills
- uPVC windows
- Patio & French doors
- Composite doors
- Timber windows & doors
Why deal with it now?
Getting a straight, even bead on an outside frame takes practice, especially on upper floors. We cut out properly, back deep gaps and tool every joint neatly, using a product chosen for the frame and wall. Older cottages and farmhouses around Thorney Island can have timber floors and frames, and water through a failed joint can rot timber if it’s left.
Leaving a failed joint normally makes the job bigger, not smaller, as water and mould keep getting in. If you are not sure whether it needs doing, ring 0345 464 0079 or email us for an honest opinion and a quote.
Why Thorney Island clients choose us
- A 12-month guarantee on all work
- Full insurance on every job
- 4.9 on Google from 180+ five-star reviews
- Homes, businesses and hotels
Take a look at what affects the cost or our reviews.
The process
Most of a good job is in the preparation, so that’s where we spend the time. Joints are cleaned back and dried before anything new goes in. In total, it usually takes a morning for a couple of windows and a door. For a village or hamlet like Thorney Island, the journey is planned in advance: tell us about narrow lanes, gates, long drives and where we can park. We bring what the job needs, so it can be finished in one trip where possible.
- First, we confirm safe access to each frame.
- Old, cracked mastic is removed completely, along with any loose debris.
- The surfaces are cleaned and left dry.
- Deep voids are backed, then the sealant is gunned in.
- The joint is shaped to shed water and the area tidied.
How to prepare
- Mention if the joints have been sealed before
- Tell us about access, such as stairs, a lift or high-level joints
- Tell us about any water getting in
Getting a quote
There’s no standard price list, as no two jobs are quite the same. Instead, we give you a clear price for your job. To arrange one, ring 0345 464 0079 or email us.