East Sussex · England
Sand mastic for sash & case windows in Crowborough, East Sussex
Sand mastic in Crowborough from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Crumbling sand mastic round a window
- Gaps between timber frames and stone or brick
- Mastic that needs renewing before redecorating
About our sand mastic in Crowborough
On many period windows, sand mastic looks right and suits the building. On modern frames we’d normally use a flexible sealant and we’ll explain which is best for yours. We work on timber door frames, tenement windows and sash and case windows, and people most often call us about draughts and rain around sash boxes and crumbling sand mastic round a window.
Walls in Crowborough that face the prevailing wind take the most weather, so the mastic there tends to fail first. It’s worth looking at every frame, not just the one that leaks.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we’ll put it right.
- Location
- Crowborough (TN6)
- Region
- East Sussex
- Cover
- 12 months on all our work
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
What sand mastic looks like in Crowborough
With historic houses such as Groombridge Place (about 4.6 miles north) nearby, there’s older building stock in the area around Crowborough as well as newer homes. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window. Rainfall in the South East is lower than in much of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Letting a property close to Crowborough station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about. For an older house near a landmark such as The Parish Church of All Saints, frames set in older brick or stone need a sealant that suits the wall as well as the frame. For site and facilities teams at buildings such as St Marys Catholic Primary School, larger buildings have plenty of frames, and the mastic around each one ages.
Crowborough is about 16 miles south of Sevenoaks, in East Sussex. Across the TN6 area, we can carry out sand mastic at your property. Our East Sussex coverage runs to 289 places, Crowborough among them. You can also see our page for Crawley, about 16 miles away.
Every address in TN6 is within our area for sand mastic, from the main roads to the quietest streets. Sand mastic is available to properties on Church Road, High Street and London Road. Crowborough is on the A26 and B2100, so it’s easy for us to get to with everything needed for sand mastic. We also cover the places around Crowborough: Jarvis Brook (1 mile east), Steel Cross (1 mile north-east), Boarshead (2 miles north-east), Sweethaws (2 miles south-west) and Marden's Hill (2 miles north-west). Larger places within reach include Lewes (14 miles south-west), Hailsham (14 miles south), Uckfield (6 miles south-west), South Malling (14 miles south-west), Heathfield (7 miles south-east) and Southover (14 miles south-west). Crowborough is among the bigger towns we cover in East Sussex.
Near you in Crowborough
We work in homes and buildings around Beacon Academy and The Crowborough Cross pub, among other places. For rail, the closest station is Crowborough station, about 1 mile south-east. Well-known places in the area include Crowborough War Memorial Hospital (0.5 miles west). Green spaces nearby include Crowborough Country Park.
Also near Crowborough
More services for Crowborough
Honest limits
New sealant can’t fix everything, and we’d rather say so up front. Sealant won’t put right:
- Whether work needs listed building consent
- Masonry that needs repairing
- Timber that has rotted
If in doubt, call 0345 464 0079 or send us an email and we’ll say what we think.
Joints and surfaces we work on
- Sash and case windows
- Brick reveals
- Period & listed homes
- Timber door frames
- Tenement windows
- Stone surrounds
Quotes for sand mastic in Crowborough
You’ll get a clear quote before we start. It takes into account:
- Whether old sealant or filler has to be cut out
- Any mould that needs treating
- Any working-time requirements on site
- The type of sealant required
We don’t show prices on the website, because each job is priced on what it involves. Call for a quick quote and we will talk you through it.
Asking for a quote
Photos help, but a description is a good start. Try to tell us:
- If someone has resealed it before
- Pictures of the joints, sent by email
- The problem you’ve noticed
- Roughly how big the job is
Want a quote for sand mastic? Please phone 0345 464 0079 or send us an email with a few details. You’ll know what we plan to do, and what it will cost, before any work begins.
DIY sealant or a professional job?
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it fails, we can still redo it.
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.
What the job involves on each surface
Brick reveals
Loose mastic comes out and deep gaps are packed before the new mastic goes in.
Stone surrounds
We take care not to mark the stone when the old mastic comes out.
Landlord and commercial work in Crowborough
Water getting past a failed joint can damage the building, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance.
Letting agents often deal with us directly. Tell us the address, the job and how access works and we’ll give you a quote.
How the visit works
When we arrive, we look over the joints with you first, so there are no surprises. Surfaces next to the work are protected before any work begins. The work usually takes a few hours per window, depending on the condition of the joints. For a job in Crowborough, we need access to where the work is and somewhere nearby to park. For outside work, let us know about side access, gates and any upper-floor joints.
- We look at the surrounds with you and agree the joints to renew.
- We remove the old, loose mastic.
- Deep gaps are packed so the mastic sits at the right depth.
- We apply the mastic by hand and shape it.
- The surface is finished to suit the stone or brick.
How to prepare
- Keep children and pets away from the work area
- For indoor joints, keep the area dry beforehand if you can
- Let us know if you’ve seen damp or leaks
Get a quote
If you are in Crowborough and need sand mastic, ring 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and you will get a clear quote before any work starts.
Advice
Common questions in Crowborough
Do you cover Crowborough for sand mastic?
Yes. We work across London and the South East, and Crowborough is part of that. Just ring 0345 464 0079 or send us an email with a few details of the job.
Is there a guarantee on sand mastic in Crowborough?
Every job comes with our one-year guarantee, wherever it is. We are fully insured, and an ARBOMaster approved applicator.
Do you offer different sealant colours?
Most of the time, yes. We will tell you which colours the right product comes in.
What do you put in the joint?
We choose the sealant for the joint, not the other way round. Movement, water and weather all affect the choice, and we will tell you what we are using.
Is consent needed for window work on a listed home?
Yes, it’s worth checking. Your local planning authority can say if consent is needed for work on a listed home or in a conservation area.
Are you insured?
Yes. We are fully insured.
Where is Mr Mastic based?
We are a Crawley-based firm. We work across South East England, London and Scotland.
Can new sealant go over the old?
No, and we never do. It can look neat for a few weeks, but the new layer lifts away from the old one. Removing the old sealant completely is the only lasting way.
Why deal with it now?
An open joint round the frame lets weather in. Water can get to the frame and the masonry so renewing it early protects the window. Draughts from a gap round a frame, damp under a sill or water behind a bath panel all start small, and they’re far easier to fix early.
Homes and businesses are quoted the same way: the amount of work, the access and the products needed, plus any working-time requirements on site. Call for a quick quote and we’ll explain what it covers.
Why book with us
- Experience in homes, commercial sites and hotels
- Approved under the ARBOMaster scheme
- Every job guaranteed for a year
- Trusted Arbo and Everbuild sealants
Take a look at what affects the cost and what customers say.