East Sussex · England
Window & door mastic in Newhaven, East Sussex
Our applicators work in Newhaven on mastic around window and door frames, sills and patio doors. Old sealant removed completely, joints prepared properly.
- Cracked or shrunken mastic around the frame
- Black, perished sealant on frames
- Water coming in at the bottom corners of a door
Window mastic in Newhaven, done properly
The mastic around a window or door seals the gap between the frame and the wall. When it cracks, hardens or pulls away, draughts and rain get in. The old mastic is removed and the joint resealed with a flexible exterior sealant. If you are dealing with rain getting in at the frame or under the sill and mastic that’s falling out in pieces, we can put it right, whatever the surface.
In a town like Newhaven, older houses sit alongside newer estates, with windows of every age. All of them depend on a sound bead of mastic between frame and wall.
Each job carries a 12-month guarantee, large or small.
- Place
- Newhaven (BN9)
- Wider area
- East Sussex
- Cover
- One year on every job
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
What window mastic looks like in Newhaven
Newhaven is close to the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. That’s hard on the mastic around window and door frames, especially on the side facing the sea. With historic houses such as Monk's House (about 3.4 miles north-west) nearby, there’s older building stock in the area around Newhaven as well as newer homes. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic.
For an older house near a landmark such as Church of St Michael and All Angels, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. Letting a property close to Newhaven Town station? Then renewing tired window mastic between tenants heads off draught and damp complaints. If you look after a building such as UTC@Harbourside, its window and door frames need their mastic kept sound, just like a home’s.
Newhaven is about 8 miles east of Brighton, in East Sussex. We provide window mastic to homes and businesses in Newhaven and nearby. We cover 289 towns and villages across East Sussex, from the larger towns to small villages. You can also see our page for Brighton, roughly 8 miles from Newhaven.
Every address in BN9 is within our area for window mastic, from the main roads to the quietest streets. We cover properties on High Street, Station Road and Dacre Road and the roads around them. Main roads around Newhaven include the A26 and A259, which makes travel easy. Other places close to Newhaven include Denton (1 mile north-east), South Heighton (1 mile north), Piddinghoe (1 mile north-west), Tide Mills (1 mile south-east) and Norton (2 miles east). Larger places within reach include Eastbourne (10 miles east), Seaford (3 miles south-east), Lewes (6 miles north), Hailsham (10 miles north-east), Uckfield (12 miles north) and Telscombe (3 miles west). Newhaven is one of the larger places we cover in East Sussex.
Around Newhaven
Locally, jobs take us to homes and businesses close to Harbour Primary and Nursery School, The Ship Hotel and Castle Hill. There’s a railway station in Newhaven itself: Newhaven Town station. Nearby you will also find Chailey Heritage Marine Hospital (1.2 miles south-east) and Newhaven Museum (0.5 miles north-east). Not far away are Itford Hill.
DIY sealant or a professional job?
The difference is mostly in the preparation and the product. We take joints back to clean, dry surfaces, and the sealant is chosen for how the joint moves and where it is, then guaranteed for a year.
A DIY attempt doesn’t rule out a professional job. We remove it and do the joint properly, so tell us about it when you ask for a quote.
How we quote for window mastic
The quote reflects the job in front of us. We take into account:
- How many areas need sealing
- Any mould that needs treating
- The amount of work
- Access and height
What it costs depends on the amount of work, how hard the old material is to remove and how easy the joints are to reach. You will have a clear quote before any work starts, so you know where you stand.
What to tell us for a quote
To help us quote quickly, let us know:
- Any previous sealing or DIY work
- The problem you’ve noticed
- Roughly how big the job is
- Any access issues, like height or stairs
Call for a quick quote, or send an email if you’d rather. Describe what needs sealing and we will talk you through the work.
Landlords, agents and businesses in Newhaven
Letting agents and landlords in Newhaven can book us as well as homeowners. Resealing between tenancies keeps a property looking cared for.
In hotels, rooms out of use cost money, so we plan the work room by room around your bookings where we can. We’ve worked in hotels as well as homes and businesses.
What the job involves on each 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.
Aluminium frames
Bi-fold and sliding aluminium doors have long frame joints, and the threshold joint takes a lot of water. Each is cleaned, backed where deep and resealed.
Keeping the joints in good condition
A little care helps the new joints last. Our advice:
- Paint up to the joint, not over it
- Walk round the house once a year and look at the joints
- Keep solvents and bleach off the sealant
- Keep jet washers away from the mastic
On timber frames, keep the paintwork in good order, because bare, wet timber moves more and pulls at the joint. Keep paint off the silicone itself.
A small gap around a frame only grows. As old mastic keeps shrinking, the gap widens, and heat escapes around the frame. Resealing closes it.
The process
Once we are on site, we compare the joints with what we discussed. If we find something unexpected, we talk it through with you first. Most jobs then take a few hours for a few frames, or a day or more for a whole house. Parking in a town like Newhaven is generally straightforward, but tell us if there’s a driveway or any restrictions, and mention if the work is upstairs, in a flat or high on the outside.
- Each frame is looked over and we agree which ones need resealing.
- We remove the old mastic and clean the frame edge and wall.
- Deep gaps get closed-cell backing rod to set the depth.
- The new sealant goes on in white, brown, anthracite grey, black or clear to suit.
- Every joint is tooled smooth and checked before we leave.
Before we arrive
- Mention any sign-in or site rules at work premises
- Keep pets and children clear of the area while we work
- Let us know if you’ve seen damp or leaks
How to get a quote
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints.
Read more
Towns and villages near Newhaven
What else we do in Newhaven
Common questions in Newhaven
I let a flat near Newhaven Town station. Can you help?
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 will give you a fixed price before we start.
Do you cover Newhaven for window mastic?
Yes, Newhaven is within the area we cover. Our work covers London and the South East. You can ring 0345 464 0079 or email us and tell us what needs doing, and we’ll give you a clear price.
Does someone need to be in?
It depends on the job. Inside work needs someone to give us access.
Is the new sealant paintable?
Most silicone cannot be painted. If you plan to paint, tell us first and we can use a paintable sealant where it suits the joint.
Are you ARBOMaster approved?
Yes. ARBOMaster is the approved applicator scheme for Arbo sealants, and we’re part of it.
Can new sealant go over the old?
No. New silicone won’t bond to old silicone, and it traps any mould or water underneath. We remove it all first.
Can resealing stop a draught around my window?
Often, yes. Air often gets in between the frame and the wall, and resealing inside and out closes it.
Where is Mr Mastic based?
Mr Mastic is based in Crawley. Our applicators cover Newhaven.
When something else is needed
Before you book, it’s worth knowing the limits too:
- Broken hinges, locks or handles
- Misting between the panes of a double-glazed unit (that needs a new unit)
- A door that needs adjusting, rehanging or new seals
If you’re not sure, just ring 0345 464 0079 or drop us an email and we’ll give you a straight answer.
Where we work in Newhaven
- Timber windows & doors
- Aluminium frames
- Window sills
- Composite doors
- Patio & French doors
- uPVC windows