Kent · England
Window & door mastic in New Barn, Kent
Mastic around window and door frames, sills and patio doors in New Barn, with a one-year guarantee on every job. Call for a quick quote.
- Rushed sealant from a window installation
- Hard, cracked sealant around windows
- Black, perished sealant on frames
About our window mastic in New Barn
Every window and door frame has a gap around it, and mastic is what closes it. When it cracks, hardens or pulls away, draughts and rain get in. Our applicators cut it out and replace it with a flexible, weatherproof sealant. If you have untidy mastic left by window fitters and mastic that has split away from the wall, we can put it right, whatever the surface.
Houses in smaller places like New Barn can stand more in the open than those in a built-up town, so exposed windows and doors face the weather head on. That’s hard on the mastic around frames and sills.
Big or small, you get the same one-year guarantee in New Barn and across Kent.
- Location
- New Barn (DA3, DA13)
- Region
- Kent
- Guarantee
- 12 months on all our work
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Why deal with it now?
A cracked joint around a frame lets rain into the wall. Over time that can mean damp patches, damaged plaster and rotting timber. Resealing now is a small job by comparison. Around New Barn, water from a failed joint in an older home can soak into timber and plaster, which is far harder to put right than the sealant itself.
Homes and businesses are quoted the same way: how much there is to do, how we reach it and what it needs, plus any working-time requirements on site. Ask us for a quote and we’ll go through it with you.
Why book with us
- 4.9 on Google from 180+ five-star reviews
- ARBOMaster approved applicator
- Full insurance on every job
- Domestic, commercial and hotel work
Take a look at what affects the cost and our reviews.
Aftercare tips
Once the sealant has cured, a few habits help it last:
- Keep jet washers away from the mastic
- Paint up to the joint, not over it
- Air rooms to keep condensation down around windows
- Keep paint and stain on wooden frames in good order
Silicone cannot normally be painted, so if you’re planning to paint the frames or walls, tell us beforehand. We can use a paintable sealant where that matters.
Look out for the warning signs: split or missing mastic, gaps, damp patches inside or black mould on the reveal. Any of these is worth a call.
Quotes for window mastic in New Barn
There’s no set price list, because no two jobs are the same. The quote depends on:
- Any working-time requirements on site
- The old material and how stubborn it is
- Whether there’s mould to deal with
- How easy the joints are to reach
The cost reflects the work involved, not a rough estimate. That’s why we ask a few questions first.
What to tell us for a quote
Photos by email are helpful but not essential. Try to tell us:
- Whether it has been sealed before
- Any access issues, like height or stairs
- Where the property is
- The type of property
Need a quote? Please ring 0345 464 0079 or email us and tell us about the job. You will know what we plan to do, and what it will cost, before any work begins.
What we are called out for in New Barn
Sills take more water than any other part of a window, and the ends of the sill, where it meets the wall, are where it gets in. When that sealant fails, water gets into the wall or under the frame.
These are the problems we’re asked about most:
- Sealant in the wrong colour for the frame
- Damp patches on the reveal after heavy rain
- Gaps where the sill meets the wall
- Old mastic that has gone black or come away
For landlords with property near Longfield station, cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets.
Questions to ask before booking
- Whether they’re fully insured
- The length of the guarantee
- Whether all the old sealant comes out first
- When the joint can take water or movement
What we do, step by step
There is not much for you to do on the day. Show us the job and we’ll take it from there. The work itself takes anything from an hour or two to a full day, depending on how many frames there are. In a smaller place like New Barn, parking is seldom the issue; lanes, gates and long drives are worth mentioning. For outside work, side access and the height of the joints help us plan.
- We check how each frame can be reached safely.
- Old, cracked mastic is removed completely.
- Frame and wall are cleaned and must be dry before sealing, and primed where the sealant calls for it.
- Deep voids are backed, then the sealant is gunned in.
- We tool the joint so water runs off, then clear up.
How to prepare
- Mention any parking rules near the property
- Tell us about any water getting in
- Keep pets and children clear of the area while we work
Ask for a quote
To get a quote, call 0345 464 0079 or drop us an email with the location and a short description of the problem. We will send you a clear quote before any work starts.
Read more
Towns and villages near New Barn
More services for New Barn
DIY sealant or a professional job?
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.
Sealing over old silicone is the commonest DIY error. Silicone doesn’t stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
Questions from New Barn
Do you cover New Barn for window mastic?
Yes. Our work covers London and the South East, and New Barn is part of that. You can ring 0345 464 0079 or send us an email and let us know what needs doing.
Do you work for landlords with property near Longfield station?
Yes. We work for landlords and letting agents as well as homeowners. Just call 0345 464 0079 or send us an email with the address and what needs doing, and we will give you a clear quote.
What sealant do you use?
Each joint gets the product that suits it. Movement, water and weather all affect the choice, and we’ll explain our choice.
Can you seal over the old sealant?
No. Fresh sealant does not stick to old sealant, and anything trapped underneath, including mould and water, stays there. We remove it all first.
Can you match the sealant to my frames?
Yes. We can use white, brown, anthracite grey, black or clear, so the joint suits the frame.
What do you need from me for a quote?
Just the basics: where it is, what you’ve noticed and how we reach it. Then ring 0345 464 0079 or send us an email.
Does someone need to be in?
If the work is inside, we need someone to let us in. After that, you can carry on with your day.
Will there be a smell?
It depends on the product. Some smell for a while, some hardly at all, and any smell fades as they cure.
New Barn homes and the weather
Historic houses like Cobham College (about 3.1 miles east) are a reminder that the area around New Barn 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 is traditional sand mastic. Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
If you live in an older home near Church of Saint Mary Magdalene, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint. Managing a site like Longfield Academy? Then larger buildings have plenty of frames, and the mastic around each one ages.
New Barn is about 3 miles south of Northfleet, in Kent. From the centre of New Barn to the outskirts, window mastic is available for homes and businesses alike. Our Kent coverage runs to 922 places, and New Barn is one of them. For nearby work, see our London page.
Postcode districts we cover here for window mastic: DA3 and DA13. Whether your property is on The Maples, Kenwood Avenue and Merileys Close or a nearby road, our applicators can take on the job. We also cover the places around New Barn: Longfield Hill (1 mile south-east), Longfield (1 mile west), Hartley (1 mile south-west), Nash Street (1 mile east) and Meopham (2 miles south-east). Further out, we also cover Maidstone (12 miles south-east), Dartford (6 miles north-west), Sevenoaks (10 miles south-west), Gravesend (3 miles north-east), Tonbridge (14 miles south) and Northfleet (3 miles north).
Landmarks near New Barn
Around New Barn, our work takes us to homes and buildings near Istead Rise Primary School and Rectory Meadow and the streets around them. The nearest railway station is Longfield station, about 1.2 miles west. Other landmarks nearby include Gravesham Museum (3.6 miles north-east) and Stone Castle (3.9 miles north-west). The countryside around New Barn includes Sawyers Lake.
When something else is needed
A few problems are outside what sealant work can do:
- A sash or casement that will not close properly
- Damp coming through the wall itself rather than the frame joint
- Draughts through the window seals rather than the frame
If you’re not sure, just call 0345 464 0079 or send us an email and we’ll give you a straight answer before you book.
Joints and surfaces we work on
- Patio & French doors
- Timber windows & doors
- Composite doors
- Aluminium frames
- Window sills
- uPVC windows