West Sussex · England
Furnace Green Sand Mastic
Sand mastic for Furnace Green and the surrounding area: the right sealant, proper preparation and a neat finish. Ask us for a quick quote.
- Mastic round period door frames that has failed
- Crumbling sand mastic round a window
- Gaps where the frame meets the masonry
Sand mastic in Furnace Green
We renew sand mastic around sash windows and doors set in stone or brick. Out comes the old, loose mastic, and new mastic is applied and shaped by hand. Common call-outs are for draughty sash windows at the surround and open joints round the window box, across sash and case windows, timber door frames and stone surrounds.
Many houses in smaller places like Furnace Green have conservatories, garden rooms or patio doors. Their glazing joints and frame seals are as much a part of the job as the windows, and any older timber or sash windows need a sealant that suits them.
You are covered for a year from the day we finish. If there’s a problem with it, please ring 0345 464 0079 or drop us an email.
- Place
- Furnace Green (RH10)
- Wider area
- West Sussex
- Cover
- A year, on every job
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Signs you need sand mastic in Furnace Green
Scraping and sanding before painting can loosen old mastic. Many people find it crumbling when they prepare the windows, which is a good time to renew it.
These are the problems we’re asked about most:
- Crumbling sand mastic round a window
- Window mastic to renew ahead of painting
- Gaps where the frame meets the masonry
- Modern sealant on a period surround
If you live in an older home near St Andrew's Church, the joint between an old wall and a newer frame is normally the first place rain gets in.
What to look for in a quote
- Is the old sealant removed completely?
- Which sealant they’ll use, and why
- What guarantee comes with the work
- What the cure time is
How the job changes by surface
Sash and case windows
A sash window’s box frame sits in the masonry opening. The gap round it is pointed with sand mastic.
Tenement and terrace windows
Where a building is shared, window work may involve neighbours so it’s worth checking responsibilities.
Can I do it myself?
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
How the visit works
The work is kept neat and contained to the joints we’re treating, so you can get on with your day. The job usually takes anything from a few hours to a full day, depending on how many windows, and we tell you how long to leave it before we go. Parking around Furnace Green is generally easier than in a town centre, but mention any lanes, gates or long drives. If the job is outside, tell us about side access and how high the joints are.
- We check each window surround and the condition of the joint.
- We rake out the old mastic and clean the joint.
- Large voids are packed out.
- We point the joint with sand mastic by hand.
- We finish the mastic to a tidy line.
How to prepare
- Where the joints are inside, avoid wetting them before we arrive
- Mention if the joints have been sealed before
- Mention any leaks or damp you’ve noticed
Getting a quote
Quotes start with a quick conversation. Describe the problem, the location and the size of the job, and we’ll explain how we’d tackle it. Whenever you’re ready, phone 0345 464 0079 or email us.
Read more
Furnace Green homes and the weather
With historic houses such as Tyes Place (about 4.3 miles south) nearby, there’s older building stock in the area around Furnace Green as well as newer homes. 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. The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Letting a property close to Three Bridges station? Then older sash windows in a rental need their mastic kept sound to keep the weather out. Schools such as Brook Infant School are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages.
Furnace Green is about 2 miles south-east of Crawley, in West Sussex. We provide sand mastic to homes and businesses in Furnace Green and the surrounding area, as part of our work across West Sussex. Furnace Green is one of 371 places in West Sussex where we work for sand mastic.
Jobs for sand mastic in RH10 is quoted and booked the same way as anywhere else. Local streets include Marion Road, Holder Road and Bolton Road, and we cover them all. Neighbouring places we cover for sand mastic include Pease Pottage (2 miles south-west), Worth Abbey (2 miles east), Balcombe Lane (2 miles south-east), Balcombe (3 miles south-east) and Staplefield (4 miles south). Larger places within reach include Horsham (7 miles west), Haywards Heath (7 miles south), Burgess Hill (10 miles south), East Grinstead (7 miles east), Billingshurst (14 miles south-west) and Bewbush (3 miles west).
Around Furnace Green
In Furnace Green, that means homes and buildings near Oriel High School, The Charcoal Burner pub and Tilgate Park. The nearest railway station is Three Bridges station, roughly 1.2 miles north. Other landmarks nearby include Crawley Museum (1.8 miles north-west) and Crawley Hospital (2 miles north-west). For a walk, there’s Tilgate Lake.
Why deal with it now?
Draughts round a sash window aren’t always the sashes. Open mastic joints round the box can let air in, and renewing the mastic closes them. Around Furnace Green, 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.
What you pay reflects the work, not a rough estimate. That’s why we ask a few questions first.
Why Furnace Green clients choose us
- We’re fully insured
- ARBOMaster approved applicator
- More than 20 years in sealant work
- Every job guaranteed for a year
Read our cost guide and what customers say.
Questions from Furnace Green
Do you cover smaller places like Furnace Green?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
I let a flat near Three Bridges station. Can you help?
Yes, rental work is part of what we do. Just call 0345 464 0079 or send us an email and tell us about the property, and we will give you a clear price.
Can I choose the sealant colour?
Normally, yes. Sealants come in white, clear, grey and other colours, and we will agree it with you first.
Is it worth trying it myself?
That depends on the joint. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional.
Do you guarantee sand mastic work?
There’s a 12-month guarantee on every job.
Is it messy?
Very little: the area around the joints is protected first, and we tidy up before we go.
What sealant do you use?
Products from Arbo and Everbuild, among others, picked for each joint. We explain the product when we quote.
When will the new mastic be hard?
Not straight away. It skins first and hardens fully later, and we will tell you what to expect.
Looking after it afterwards
Looking after new joints is easy, and it makes a real difference:
- Clear gutters so water does not pour onto the windows
- Leave the new mastic unpainted
- Avoid patching sand mastic with silicone
- Ask the planning authority about consent for listed or conservation-area homes
Keep gutters and sills clear so water runs away from the surround. Water sitting against the mastic shortens its life.
Small cracks are a sign the mastic is ageing. Renewing it then is simpler than waiting until it falls out.
Places near Furnace Green
Also in Furnace Green
How we quote for sand mastic
Some jobs are bigger than they look, and some smaller. The main factors:
- How many areas need sealing
- Whether the work is at height
- The size of the job
- When we can work, for business premises
What it costs depends on how much there is to do, how much old material has to come out and how easy the joints are to reach. We give a clear quote before we start, so you know where you stand.
Helping us quote
The more you tell us, the more accurate the quote. When you ask for a quote, tell us:
- The rough size of the job
- How we’d reach the joints
- The address or postcode of the job
- Whether it has been sealed before
Asking for a quote is easy: let us know the job and the location. A few pictures by email make the job easier to understand, and we will take it from there.