Hampshire · England
Cowplain Window Mastic
Our applicators work in Cowplain on mastic around window and door frames, sills and patio doors. Old sealant removed completely, joints prepared properly and a one-year guarantee.
- Leaking joints at the ends of sills
- Draughty joints inside around the window
- Mastic that’s falling out in pieces
Aftercare tips
A little care helps the new joints last. Our advice:
- Check the mastic once a year
- Clear any debris from frame drain holes
- Keep timber frames painted
- Do not paint over the silicone
Check the drainage slots in the frames are not blocked, so rain drains out rather than building up at the sealant.
Leaks usually show up in wet, windy weather, but resealing works best in dry conditions. Sorting cracked mastic early means the joint is sound before the bad weather.
Window mastic in Cowplain
Homes in Cowplain have every kind of window: from uPVC casements to timber and aluminium, plus patio doors, French doors and sills. The sealant is chosen to suit the frame material and the wall. If you have mastic that’s falling out in pieces and gaps left after new windows were fitted, we can put it right, on uPVC windows, timber windows & doors and aluminium frames alike.
In a smaller place like Cowplain, some walls face open ground and catch the full force of the weather, so exposed windows and doors face the weather head on. The mastic around frames on those walls tends to age faster.
All of our work is guaranteed for twelve months, in Cowplain and everywhere else we cover.
- Where
- Cowplain (PO8, PO7)
- Region
- Hampshire
- Guarantee
- One year on every job
- Quote
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Other services in Cowplain
Why deal with it now?
A quick bead over the top of old mastic looks like an easy fix, but it will not grip old, dirty sealant. It soon lifts and the leak carries on behind it. The old mastic has to come out. Homes in smaller places like Cowplain can face more weather, and failed outside joints let damp into walls. Inside, a split seal lets water into floors and panels just as it would anywhere.
Homes and businesses are quoted the same way: the amount of work, the access and the products needed, plus any working-time requirements on site. Ask us for a quote and we’ll go through it with you.
Why Cowplain customers choose us
- Full insurance on every job
- Quality sealants from Arbo and Everbuild
- White, clear, grey or coloured to suit, where the product allows
- We agree the colour with you first
See what affects the cost and our reviews.
What happens on the day
We keep the work tidy and contained to the joints we are treating, so you can get on with your day. The job generally takes a few hours for a few frames, or a day or more for a whole house. For a job in Cowplain, we agree the time, the access and parking before the day. Outdoor jobs depend on a dry day, since sealant needs a dry surface.
- We check each frame and agree which ones need doing.
- Next the failed sealant is cut away and the joint cleaned.
- Deep gaps are filled with backing rod to set the depth.
- We apply a weatherproof sealant to match the frame and tool it neatly.
- Finally we tidy up and check each joint.
Getting ready for the visit
- Let us know if you’ve seen damp or leaks
- Mention any sign-in or site rules at work premises
- Try not to wet indoor joints just before the visit
Get a quote
Call for a quick quote, or send an email if you’d rather. Describe what needs sealing and we’ll explain what’s involved and send you a clear quote.
Advice
Different surfaces, different methods
Patio & French doors
Patio and French doors have the longest joints on most houses. Most leaks start at the bottom corners, so we pay close attention there.
Window sills
Stone and concrete sills have their own joints, and the joint under the frame can let rain run behind. We seal those with a sealant suited to masonry.
How we quote for window mastic
Every job gets its own quote. These are the things that affect it:
- The old material and how stubborn it is
- How many rooms, windows or areas are involved
- Whether the work is at height
- Any working-time requirements on site
The cost reflects the work involved, not guesswork. That is why we ask a few questions first.
Helping us quote
To make quoting easier, let us know:
- The problem you’ve noticed
- How many joints, rooms or windows are involved
- Photos by email, if that’s easy
- The type of property
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is, and we’ll explain how we’d tackle it. When it suits you, call 0345 464 0079 or send us an email.
Landlords, agents and businesses in Cowplain
Businesses can book us for washrooms, kitchens, offices and more. On commercial sites, working times can be discussed when we quote.
Mouldy or split sealant often shows up at the end of a tenancy. We can quote for more than one property at once.
Your questions about window mastic in Cowplain
Do you work for landlords with property near Rowlands Castle station?
Yes, rental work is part of what we do. You can call 0345 464 0079 or send us an email with the address and a few details, and we’ll give you a fixed price before we start.
Do you cover Cowplain for window mastic?
Yes, Cowplain is within the area we cover. Our work covers London and the South East. Just call 0345 464 0079 or drop us an email with a few details of the job.
Is the new sealant paintable?
Not generally, if it’s silicone. We choose the product with your decorating in mind, so mention it when you book.
Is it OK to seal over old sealant?
No, it will not last. It may look fine at first, but the new bead soon lifts. Removing the old sealant completely is the only lasting way.
How long does it take to reseal the windows on a house?
It depends on access, the old mastic and the size of the frames. You will know the timing when we quote.
Will you leave a mess?
Not at all. The area is protected while we work and cleaned up afterwards.
Do you remove the old sealant?
Yes. We cut out all the old sealant and clean the joint.
Do you seal inside as well as outside?
Yes. Indoors, we seal between the frame and the plaster or reveal.
What we are called out for in Cowplain
Joint shape matters as much as the product. A thin smear across a wide gap has nothing to it, while a joint packed solid cannot stretch. That is what backing rod is for.
Common reasons people contact us include:
- Old mastic that has gone black or come away
- Gaps between the frame and the inside reveal
- Cracked or shrunken mastic around the frame
- Whistling draughts around closed windows
For an older house near a landmark such as The Hart Plain Church, the joint between an old wall and a newer frame is generally the first place rain gets in.
What your quote should include
- How hidden problems are handled
- Whether they seal over old material or remove it
- When the joint can take water or movement
- Whether VAT is included
Frames and glazing around Cowplain
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. With historic houses such as Warblington Castle (about 4.5 miles south-east) nearby, there’s older building stock in the area around Cowplain as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
For landlords with property near Rowlands Castle station, sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. If you look after a building such as Woodcroft Primary, its window and door frames need their mastic kept sound, just like a home’s.
Cowplain is about 1 mile south-west of Horndean, in Hampshire. If you need window mastic in Cowplain, please phone 0345 464 0079 or send us an email for a quick quote. We cover Hampshire from our Crawley base. Cowplain is one of 683 places in Hampshire we cover for window mastic. Portsmouth is on our list too, about 7 miles from Cowplain.
Jobs for window mastic in PO8 and PO7 works the same way as everywhere else we cover. Streets in the area include Milton Road, King's Road and London Road. Other places close to Cowplain include Hart Plain (1 mile south-west), Waterlooville (1 mile south), Soake (1 mile west), Furzeley Corner (2 miles west) and Purbrook (2 miles south). Larger places within reach include Gosport (9 miles south-west), Havant (3 miles south-east), Eastleigh (15 miles west), Fareham (8 miles south-west), Hedge End (12 miles west) and Petersfield (8 miles north-east).
Near you in Cowplain
In Cowplain, that means homes and buildings near The Cowplain School, among other places. The closest station to Cowplain is Rowlands Castle station, about 3 miles east. A little further out are Havant Museum (3.9 miles south-east) and Havant War Memorial Hospital (3.5 miles south-east). Open spaces near Cowplain include Windmill Hill and Southmoor Nature Reserve.