Kent · England
Sand mastic for sash & case windows in New Barn, Kent
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for New Barn, backed by a 12-month guarantee. Ask us for a quote.
- Cracked mastic round a front door frame
- Gaps where the frame meets the masonry
- Modern sealant on a period surround
Do you need sand mastic in New Barn?
Scraping and sanding before painting can loosen old mastic. It’s often found when windows are being prepared for paint, which is a good time to renew it.
If you can see any of these, it’s time to have the joints looked at:
- Mastic that needs renewing before redecorating
- Cement or filler used on old window joints that has cracked
- Open joints round the window box
- Draughts and rain around sash boxes
In the older streets around Church of Saint Mary Magdalene, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Comparing quotes
- Whether they seal over old material or remove it
- Is VAT in the price?
- How hidden problems are handled
- How the surfaces are prepared before sealing
Sand mastic in New Barn
Fresh sand mastic forms a skin quite soon, but it takes longer to harden fully. Traditionally, sand mastic is left unpainted and we’ll advise if you are redecorating. If you’re dealing with gaps where the frame meets the masonry and draughty sash windows at the surround, we can help, on period & listed homes, brick reveals and sash and case windows alike.
Houses in smaller places like New Barn can stand more in the open than those in a built-up town. The mastic around frames on those walls tends to age faster.
There’s a 12-month guarantee on every job.
- Location
- New Barn (DA3, DA13)
- Region
- Kent
- Guarantee
- One year on every job
- Quotes
- A clear price before we start
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
How to look after the new joints
How long the joints last depends on use and care. Here’s what we suggest:
- Ask us before painting near the mastic
- Ask a joiner to look at soft timber first
- Go gently near the mastic when preparing windows
- Make sure water runs off the sill
Don’t touch or press the mastic while it hardens. It forms a skin fairly soon but needs longer to fully harden.
Small cracks are a sign the mastic is ageing. It’s easier to renew it before it drops out.
DIY versus a professional finish
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, then guaranteed for a year.
Landlord and commercial work in New Barn
Mouldy or split sealant often shows up at the end of a tenancy, and it’s quick to put right between tenancies. We can quote for more than one property at once.
Whether it’s one flat or a portfolio, the work is the same standard: old sealant fully removed, joints prepared properly and a one-year guarantee.
Sand mastic in New Barn: local notes
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. Where a home is older, 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, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Letting a property close to Longfield station? Then any sash windows need sound mastic to keep draughts and rain out. For site and facilities teams at buildings such as Longfield Academy, its window and door frames need their mastic kept sound, just like a home’s.
New Barn is about 3 miles south of Northfleet, in Kent. Anywhere in DA3, we cover sand mastic for homes and businesses. New Barn is one of 922 towns and villages in Kent we cover. There’s also a page for London, about 20 miles away.
Every address in DA3 and DA13 is covered for sand mastic. You’ll find streets such as The Maples, Kenwood Avenue and Merileys Close, and we cover them all. If you are just outside New Barn, we cover 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).
Local landmarks in New Barn
In New Barn, that means homes and buildings near Istead Rise Primary School and Rectory Meadow and the streets around them. The closest station to New Barn is Longfield station, about 1.2 miles west of the centre. Nearby you’ll also find Gravesham Museum (3.6 miles north-east) and Stone Castle (3.9 miles north-west). Not far away are Sawyers Lake.
Quotes for sand mastic in New Barn
Your quote is based on your job. We take into account:
- The amount of work
- The number of rooms or windows
- How easy the joints are to reach
- Which sealant suits the joint
The cost depends on the size of the job, how much old material has to come out and access to the work. We give a clear quote before we start, so you know where you stand.
What to tell us for a quote
You don’t need to know the technical terms. It helps if you can tell us:
- Whether it has been sealed before
- Where the property is
- Photos by email, if that’s easy
- What the problem is, such as mould, gaps, leaks or cracking
If you are in New Barn and need sand mastic, ring 0345 464 0079 or drop us an email. A short description of the job and where it is helps us quote, and we will agree the price before any work begins.
Places near New Barn
What else we do in New Barn
What sealant work can’t fix
New sealant cannot fix everything, and we’d rather say so up front. It won’t solve:
- Whether work needs listed building consent
- Sashes that need overhauling
- Putty and glazing repairs
If in doubt, call 0345 464 0079 or drop us an email and we’ll say what we think before you book.
Joints and surfaces we work on
- Tenement windows
- Period & listed homes
- Brick reveals
- Stone surrounds
- Timber door frames
- Sash and case windows
How the visit works
Our applicators work methodically: protect, prepare, seal, tidy. Typically it takes a few hours per window, depending on the condition of the joints. A visit to New Barn is planned like any other: the time, the access and where to park are agreed in advance. If the work is outside, the weather plays a part, as sealant needs a dry surface.
- Each surround is checked first.
- The joint is raked out and cleaned.
- Large voids are packed out.
- New sand mastic is applied and shaped by hand.
- The finish is dressed neatly.
Preparing for the visit
- Mention if the joints have been sealed before
- Keep pets and children clear of the area while we work
- Tell us about access, such as stairs, a lift or high-level joints
How to get a quote
There’s no standard price list, because every job is different. Instead, we give you a clear quote for your job. To get started, ring 0345 464 0079 or send us an email.
Related advice
FAQs for New Barn
Will you come out to New Barn?
Yes. New Barn is within the area we cover, which takes in towns, villages and rural addresses. We work across London and the South East. Just mention lanes, gates or anything else about the route when you book.
Is New Barn in your area for sand mastic?
Yes. Our work covers London and the South East, and New Barn is part of that. Just call 0345 464 0079 or send us an email with a few details of the job.
Can landlords and businesses book you?
Yes. We work in homes, commercial premises and hotels.
Can I add another job to the visit?
Yes. Just list everything you need and we will quote it together.
Do you do commercial work?
Yes, regularly. Larger jobs can be planned room by room or area by area to suit the site.
Should I try DIY first?
You can, for simple jobs. The key is preparation: remove all the old material and work on a clean, dry joint. If it doesn’t work out, we can redo it.
How long will you be here?
It depends on the size of the job, but most jobs take anything from a few hours to a full day, depending on how many windows. We will tell you when we quote.
Are you fully insured?
Yes. Full insurance covers our work, and we can confirm the details when we quote.