East Sussex · England
Window Mastic in Northiam
Window mastic in Northiam from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Rushed sealant from a window installation
- Mastic that has split away from the wall
- Cracked internal joints between frame and plaster
How we handle window mastic in Northiam
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. Typical jobs include draughty joints inside around the window and untidy mastic left by window fitters, across aluminium frames, patio & French doors and uPVC windows.
Outdoor sealant needs dry, clean surfaces, so work on frames around Northiam is planned for dry weather. Tell us about access to every side of the house, including upper-floor windows.
All of our work is guaranteed for twelve months.
- Location
- Northiam (TN31)
- Region
- East Sussex
- Guarantee
- A year, on every job
- Quote
- A clear price before work begins
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
What we do, step by step
When we get to you, we check the joints match what you told us. If anything is different, we explain it before carrying on. After that, the work takes a morning for a couple of windows and a door. Somewhere as small as Northiam, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- Each frame is looked over and we agree which ones need resealing.
- The old mastic is cut out and scraped back to clean surfaces.
- Where the gap is deep, backing rod goes in first.
- A flexible exterior sealant is applied in a colour to suit the frame.
- Every joint is tooled smooth and checked before we leave.
How to prepare
- Tell us about any water getting in
- Where the joints are inside, avoid wetting them before we arrive
- Tell us if parking is tricky
Getting a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints, and email pictures if that is easy.
Advice
Can I do it myself?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and doesn’t move well, and getting the depth right matters as much as the look.
If you’ve already had a go yourself, that’s fine. We cut it out and start again.
Surface by surface
uPVC windows
Plastic frames move a lot between a hot afternoon and a cold night, so the joint needs a low-modulus sealant that stays flexible. We match white, brown, anthracite grey and black frames.
Timber windows & doors
Wood swells when it’s wet and shrinks when it dries, so a flexible sealant is essential. The paint or stain needs to be sound where the sealant meets it.
For landlords and businesses
Letting agents often deal with us directly. Tell us the address, the job and how access works and we’ll quote.
We also work for property managers and facilities teams in Northiam and across East Sussex. Several sites can go on one quote.
Nearby places to Northiam
Other services in Northiam
Frames and glazing around Northiam
Historic houses like Great Dixter (about 0.5 miles west) are a reminder that the area around Northiam has older buildings as well as new. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that’s traditional sand mastic. 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.
Historic houses such as Great Dixter, about 0.5 miles west, show how far back building around Northiam goes, and older homes nearby need a sealant that suits their walls.
Northiam is about 9 miles north of Hastings, in East Sussex. Anywhere in TN31, our applicators can take on window mastic. Our East Sussex coverage runs to 289 places, and Northiam is one of them. For nearby work, see our Brighton page.
We cover every part of TN31 for window mastic and the streets around it. Window mastic is available to properties on Station Road, Main Street and Elizabeth Gardens and the roads around them. You will find Northiam on the A268, so it’s easy for us to get to. If you’re just outside Northiam, we cover Beckley (2 miles south-east), Beckley Furnace (3 miles south), Broad Oak (3 miles south), Flackley Ash (3 miles east) and Broadland Row (4 miles south). Within a short drive, we also cover Hastings (9 miles south), Bexhill-on-Sea (12 miles south-west), St Leonards (10 miles south), Hastings Old Town (10 miles south), Belmont (10 miles south) and Heathfield (15 miles west).
What’s near Northiam
Around Northiam, our work takes us to homes and buildings near Hayes Arms Hotel. Well-known places in the area include The C.M Booth Collection (4 miles north). Open spaces near Northiam include Flatropers Wood.
Common problems we fix in Northiam
Joints that are too thin or too deep fail early. A thin smear across a wide gap has nothing to it, and a gap filled solid can’t flex. That is what backing rod is for.
Most people get in touch after spotting one of these:
- Rain getting in at the frame or under the sill
- A bead that doesn’t match the frame
- Old mastic that has gone black or come away
- Untidy mastic left by window fitters
Managing a site like Northiam Church of England Primary School? Then the mastic around its windows and doors needs looking after like any other building’s.
Comparing quotes
- How the colour is chosen
- Who does the work, and how experienced they are
- What happens if they find a problem under the old sealant
- Whether they seal over old material or remove it
When it is not the sealant
Some problems need a builder, plumber or other trade rather than us:
- Damp problems in the wall away from the window
- Misting between the panes of a double-glazed unit (that needs a new unit)
- Faulty window hardware
Not sure which it is? You can phone 0345 464 0079 or email us and we will tell you honestly before you book.
Where we work in Northiam
- uPVC windows
- Composite doors
- Window sills
- Timber windows & doors
- Aluminium frames
- Patio & French doors
Looking after it afterwards
No joint lasts for ever, but care makes a real difference. Our tips:
- Keep paint off silicone joints
- Keep drainage slots and sill grooves clear
- Avoid harsh chemicals near the mastic
- Ventilate rooms so frames don’t stay wet inside
A yearly look round the frames is enough. Small splits are simple to catch before they leak.
Draughts get worse, not better. As old mastic keeps shrinking, the gap widens, and heat escapes around the frame. Resealing closes it.
Common questions in Northiam
Do you cover Northiam for window mastic?
Yes, Northiam is within the area we cover. Our work covers London and the South East. Just phone 0345 464 0079 or send us an email with a few details of the job, and we will give you a clear price.
Do you cover smaller places like Northiam?
Yes. Northiam 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.
Will resealing my frames help with draughts?
If the draught is coming in around the frame, yes. If it’s coming through the window seals, we’ll tell you.
Can you reach windows above the ground floor?
Yes, if safe access is possible. For high or awkward windows, we’ll tell you what access is needed.
What does window mastic cost?
The cost depends on the size of the job, access and how much old sealant has to come out. Ask us for a quote.
Does someone need to be in?
Access is agreed with you when the job is booked. Indoors, that generally means someone at home.
Will the old sealant be removed?
Yes. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Can you seal over the old sealant?
No, it won’t last. It can look neat for a few weeks, but the new layer lifts away from the old one. The old sealant has to come out completely.