West Sussex · England
Window & door mastic in Runcton, West Sussex
Mastic around window and door frames, sills and patio doors for homes and businesses in Runcton and across West Sussex. ARBOMaster approved applicators, fully insured, with a 12-month guarantee.
- Draughty joints inside around the window
- Cracked or shrunken mastic around the frame
- Whistling draughts around closed windows
Keeping the joints in good condition
Once the sealant has cured, a few habits help it last:
- Make sure the drainage slots are not blocked
- Don’t paint over the silicone
- Repaint timber before it’s bare
- Look round the frames every year or so
A yearly look round the frames is enough. Cracks and lifting edges are easy to spot early.
Water trapped behind a failed joint can start rot in timber frames and sills. Rotten timber needs a joiner, not a sealant, so early resealing is worth it.
How we handle window mastic in Runcton
Mr Mastic’s applicators have more than 20 years’ experience with window and door sealants. We’re fully insured ARBOMaster approved applicators, and every job is covered by a 12-month guarantee. We work on uPVC windows, composite doors and window sills, and people most often call us about leaking joints at the ends of sills and white mastic on grey or black frames.
Around Runcton, many homes face open ground, so their windows and doors take the full weather. Exposed frames and sills lose their mastic sooner than sheltered ones.
Big or small, it’s backed by our one-year guarantee in Runcton and across West Sussex.
- Location
- Runcton (PO20)
- Region
- West Sussex
- Guarantee
- A year, on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
What happens on the day
You do not need to clear the whole room or building before we come, just the space around the work. Everything nearby is protected, and the job takes a morning for a couple of windows and a door for a typical job. In a small place like Runcton, access is usually the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- First, we confirm safe access to each frame.
- All the failed sealant is cut away.
- Frame and wall are cleaned and must be dry before sealing, and primed where the sealant calls for it.
- Backing rod fills deep voids and the sealant goes in on top.
- The joint is shaped to shed water and the area tidied.
Getting ready for the visit
- Try not to wet indoor joints just before the visit
- Let us know about parking restrictions
- Tell us about any previous sealing or DIY attempts
How to get a quote
Need a quote? Please ring 0345 464 0079 or send us an email with a few details. We’ll explain what we’d do and give you a clear quote before any work starts.
Related advice
Different surfaces, different methods
uPVC windows
The frame is cleaned with a product that won’t harm the plastic, then the sealant goes in between frame and wall and tooled smooth.
Aluminium frames
Large aluminium doors have long joints down each side and across the head, and the threshold joint takes a lot of water. Each is cleaned, backed where deep and resealed.
Runcton homes and the weather
Runcton is close to the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. Both are hard on the mastic around window and door frames, which can dry out and crack sooner where a building faces the weather. 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.
If you live in an older home near The Parish Church of St Stephen, the joint between an old wall and a newer frame is usually the first place rain gets in. Letting a property close to Chichester station? Then renewing tired window mastic between tenants heads off draught and damp complaints. If you look after a building such as North Mundham Primary School, larger buildings have plenty of frames, and the mastic around each one ages.
Runcton is about 2 miles south-east of Chichester, in West Sussex. Across the PO20 area, our applicators can take on window mastic. Across West Sussex, we cover 371 places, and Runcton is one of them. We also work in Portsmouth, around 14 miles away.
All of PO20 is covered for window mastic. Window mastic is available to properties on Goodwood Gardens, Brookside and Lagness Road. Neighbouring places we cover for window mastic include North Mundham (1 mile west), Merston (1 mile north-east), Lagness (1 mile south-east), Hunston (1 mile west) and Portfield (2 miles north). Further out, we also cover Worthing (15 miles east), Bognor Regis (3 miles south-east), Selsey (6 miles south), Littlehampton (9 miles east), Emsworth (9 miles west) and Rustington (10 miles east).
Near you in Runcton
Locally, jobs take us to homes and businesses close to Chichester High School For Girls, among other places. For rail, the closest station is Chichester station, roughly 1.9 miles north-west. Well-known places in the area include Chichester Castle (2.1 miles north-west) and The Chichester City Museum (2 miles north-west).
DIY versus a professional finish
The difference is mostly in the preparation and the product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, and the work is guaranteed for a year.
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
Also near Runcton
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Common questions in Runcton
Can you help a landlord with a rental near Chichester station?
Yes, rental work is part of what we do. Just phone 0345 464 0079 or send us an email and tell us about the property, and we will give you a clear price.
Does living near the coast affect window mastic in Runcton?
Near the sea, outside joints face more wind, rain and salt than they would inland, so the choice of sealant and the preparation matter even more. It’s worth checking the walls that face the sea first.
Is it OK to seal over old sealant?
No. We remove every bit of old sealant first, so the new joint bonds to clean surfaces.
Is the new sealant paintable?
It depends on the sealant. Some hybrid sealants can be painted; silicone cannot. Tell us if you are decorating and we’ll choose accordingly.
Will there be a smell?
Sometimes, a little. It fades as the sealant cures.
When is the sealant fully cured?
Most sealants are touch-dry well before they’re fully cured. We will give you the cure time for the product we used before we leave.
Do you remove the old sealant?
Yes, every time. New silicone doesn’t stick to old silicone, so the joint is cleaned back first.
Do you guarantee window mastic?
Yes, for 12 months. A yearly look at the joints helps them last.
Landlord and commercial work in Runcton
Businesses can book us for washrooms, kitchens, offices and more. On commercial sites, working times can be discussed when we quote.
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Resealing at the right time is simple maintenance that we can handle for you.
Why act early in Runcton
Once mastic fails, rain can get between the frame and the wall. Left long enough, it can stain inside walls, spoil plaster and rot wooden frames. A reseal is a much smaller job. In a small place like Runcton, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
Doing several joints on one visit is normally more efficient than separate visits, so tell us about everything that needs sealing. You’ll get one clear quote for the whole job.
Why Runcton clients choose us
- Full insurance on every job
- Neat joints and a tidy finish
- 20+ years of sealant experience
- Anti-fungal silicone where joints get wet
Read our cost guide or what customers say.
Quotes for window mastic in Runcton
Some jobs are bigger than they look, and some smaller. The main factors:
- Which sealant suits the joint
- Whether the work is at height
- How much there is to do
- The number of rooms or windows
Homes and businesses are quoted the same way: how much there is to do, how we reach it and what it needs, along with when we can work on site. Call for a quick quote and we will go through it with you.
Helping us quote
When you contact us, these details help:
- If someone has resealed it before
- Where the property is
- Access, such as stairs, a lift or height
- If it’s domestic, commercial or a hotel
We do not publish a price list, as no two jobs are quite the same. Instead, your job gets its own clear quote. To arrange one, ring 0345 464 0079 or send us an email.