Hampshire · England
Four Marks Window Mastic
Window mastic for Four Marks, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Cracked internal joints between frame and plaster
- Damp patches on the reveal after heavy rain
- Gaps where the sill meets the wall
Do you need window mastic in Four Marks?
Timber windows bring their own problems. Old mastic gets painted over and cracks under the paint, and timber moves with moisture as well as temperature.
Any of these means the joints need attention:
- Hard, cracked sealant around windows
- Draughty joints inside around the window
- Sealant in the wrong colour for the frame
- Mastic that is falling out in pieces
Schools such as Four Marks Church of England Primary School are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages.
Before booking anyone
- What guarantee comes with the work
- How hidden problems are handled
- Whether they seal over old material or remove it
- What preparation is included
Window mastic for homes and businesses in Four Marks
Colour matters on a frame. White, brown, anthracite grey, black and clear sealants are all available, so the bead blends with the window rather than framing it. If you’re dealing with leaking joints at the ends of sills and gaps left after new windows were fitted, we can help, on aluminium frames, composite doors and patio & French doors alike.
Homes around Four Marks range from older properties to newer houses, and their windows range just as widely. The right sealant depends on the frame and on what it sits in.
You get a 12-month guarantee, the same in Four Marks as everywhere else we work.
- Where
- Four Marks (GU34)
- Region
- Hampshire
- Cover
- One year on every job
- Price
- A clear quote up front
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Surface by surface
uPVC windows
The frame is cleaned with a product that will not harm the plastic, then the sealant goes in between frame and wall.
Patio & French doors
The joints around patio doors run a long way, top, sides and threshold. Most leaks start at the bottom corners, so they get particular care.
FAQs for Four Marks
Can you do window mastic in Four Marks?
Yes. We work across London and the South East, and Four Marks is part of that. You can call 0345 464 0079 or drop us an email and tell us what needs doing, and we’ll give you a clear price.
Do you work for landlords with property near Alton station?
Yes, we work for landlords and letting agents. You can ring 0345 464 0079 or drop us an email with the address and a few details, and we’ll give you a fixed price before work begins.
Does someone need to be in?
For indoor joints, yes, someone needs to let us in. Once we’ve agreed the job, you don’t need to watch us work.
Is there any odour?
Sometimes, a little. Any smell clears as the sealant cures.
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.
Is the work guaranteed?
Yes. All our work carries a 12-month guarantee, and we are ARBOMaster approved applicators.
Are you insured?
Yes. We’re fully insured, and we can confirm the details when we quote.
What does window mastic cost?
There’s no set price, as it depends on the job: how much there is, what’s there now, how we reach it and what it needs. We agree the price before any work begins.
Nearby places to Four Marks
Also in Four Marks
Can I do it myself?
A DIY attempt does not rule out a professional job. We remove it and do the joint properly, so tell us about it when you ask for a quote.
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs call for the right materials, safe access and experience.
The process
There isn’t much for you to do on the day. Point us to the joints and we’ll get on with it. The job generally takes anything from an hour or two to a full day, depending on how many frames there are, including the tidy-up. For a job in Four Marks, we agree the time, the access and parking before the day. If the work is outside, the weather plays a part, as sealant needs a dry surface.
- We check each frame and agree which ones need doing.
- We remove the old mastic and clean the frame and the wall.
- Deep gaps are filled with backing rod to set the depth.
- New exterior sealant goes on in a matching colour and is tooled smooth.
- We clear up and check every joint is fully closed.
Getting ready for the visit
- Try not to wet indoor joints just before the visit
- Keep pets and children clear of the area while we work
- Mention any sign-in or site rules at work premises
Get a quote
Every job is quoted individually. Just call 0345 464 0079 or drop us an email with the details, and photos are welcome.
Read more
How to look after the new joints
How long the joints last depends on use and care. We suggest:
- Clean frames with a soft cloth and soapy water
- Keep solvents and bleach off the sealant
- Keep paint and stain on wooden frames in good order
- Check the mastic once a year
Clean the frames with mild soapy water, and keep solvents and harsh chemicals off the joint.
Water trapped behind a failed joint can start rot in timber frames and sills. Once wood has rotted, it needs repair before it can be sealed, so it pays to reseal before that happens.
Four Marks homes and the weather
Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. Historic houses like Bentworth Hall (about 2.7 miles north) are a reminder that the area around Four Marks 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.
Rented homes near Alton station change hands often, and renewing tired window mastic between tenants heads off draught and damp complaints. For an older house near a landmark such as Church of the Good Shepherd, the joint between an old wall and a newer frame is usually the first place rain gets in.
Four Marks is about 4 miles south-west of Alton, in Hampshire. Our applicators cover window mastic for homeowners, landlords and businesses in Four Marks and the surrounding area. Four Marks is one of 683 places in Hampshire we cover for window mastic. There’s also a page for Southampton, about 20 miles away.
Postcode districts we cover here for window mastic: GU34. That includes homes and businesses on Read's Field, River Close and Chalk Close. We also cover the places around Four Marks: Medstead (1 mile north), Soldridge (1 mile west), South Town (2 miles north-west), New Copse (2 miles north) and Hattingley (2 miles north-west). We also work in nearby towns such as Basingstoke (11 miles north), Winchester (12 miles west), Fleet (15 miles north-east), Horndean (14 miles south), Alton (4 miles north-east) and Petersfield (9 miles south-east).
Landmarks near Four Marks
The nearest railway station is Alton station, about 4.6 miles north-east. Well-known places in the area include Barton Castle (3.5 miles north-west) and Alton Community Hospital (3.3 miles north-east). Not far away are Red Hill.
When it is not the sealant
Some problems need a builder, plumber or other trade rather than us:
- A sash or casement that won’t close properly
- Damp problems in the wall away from the window
- Rotten timber, which needs a joiner first
If in doubt, ring 0345 464 0079 or send us an email and we’ll say what we think.
What we seal
- uPVC windows
- Aluminium frames
- Window sills
- Composite doors
- Timber windows & doors
- Patio & French doors
What affects the cost of window mastic
Jobs vary more than people expect. What affects the quote:
- Whether there’s mould to deal with
- The number of rooms or windows
- The number and length of the joints
- The product the joint needs
A failed joint rarely gets cheaper to fix by waiting, as water and mould keep getting in. If you’re not sure whether it needs doing, call 0345 464 0079 or send us an email and we will give you an honest view and a quote.
Helping us quote
Photos by email are helpful but not essential. Try to tell us:
- A few photos by email, if you can
- Where the property is
- The type of property
- Any previous sealing or DIY work
If you’re in Four Marks and need window mastic, phone 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and you’ll get a clear quote before work begins.