West Sussex · England
Sand Mastic in Horsham
Sand mastic across Horsham and nearby, with every bit of old sealant taken out first and a 12-month guarantee.
- A silicone bead on a sash window that spoils the look
- Gaps where the frame meets the masonry
- Weathered mastic on the most exposed windows
Quotes for sand mastic in Horsham
Some jobs are bigger than they look, and some smaller. What affects the quote:
- The amount of work
- Any working-time requirements on site
- The product the joint needs
- Access and height
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 do not need to know the technical terms. It helps if you can tell us:
- Any previous sealing or DIY work
- Access, such as stairs, a lift or height
- A few pictures by email, if you can
- If it’s domestic, commercial or a hotel
We quote each job on its own, so start by telling us what you need. Simply call 0345 464 0079 or send us an email and describe the job, and pictures are welcome.
How we handle sand mastic in Horsham
Burnt sand mastic is a traditional material blends with stone and brick surrounds. It’s a good fit for period properties, where modern sealant can look out of place. We’re often asked to deal with gaps between timber frames and stone or brick and patchy fillers round a sash window, on sash and case windows, period & listed homes and brick reveals.
With a large rental market, Horsham has plenty of windows that landlords need to keep weathertight. Gaps around a frame let in draughts and water, and tenants notice.
All of our work is guaranteed for twelve months.
- Place
- Horsham (RH12, RH13, RH20, BN44)
- Wider area
- West Sussex
- Guarantee
- A year, on every job
- Quotes
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Do you need sand mastic in Horsham?
Timber swells and shrinks with the weather. That movement opens up the mastic joint over time.
It’s worth asking for a quote if you see:
- Old cement repairs round a window that have failed
- Mastic dropping out of the joint
- Failed mastic on an exposed elevation
- Silicone on a period window that looks wrong
If you live in an older home near Hope Chapel, the joint between an old wall and a newer frame is generally the first place rain gets in.
What to look for in a quote
- What happens if they find a problem under the old sealant
- Which sealant they’ll use, and why
- Whether VAT is included
- Who turns up on the day
How to look after the new joints
To keep the joints looking good and working properly:
- Renew mastic before redecorating the windows
- Ask us before painting near the mastic
- Avoid heavy scraping on the mastic joint
- Make sure water runs off the sill
Keep gutters and sills clear so water runs away from the surround. Constant wetting wears the mastic faster.
Crumbling mastic lets rain into the joint. It can soak into the frame and the surrounding masonry, so renewing it early is worth it.
Frames and glazing around Horsham
London and the South East are among the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
For landlords with property near Horsham station, any sash windows need sound mastic to keep draughts and rain out.
Horsham is about 31 miles south of London, in West Sussex. We carry out sand mastic for homeowners, landlords and businesses in Horsham and nearby, as part of our work across West Sussex. Across West Sussex, we cover 371 places, Horsham among them. Crawley is on our list too, around 7 miles away.
Every address in RH12, RH13, RH20 and BN44 is within our area for sand mastic. Sand mastic is available to properties on Station Road, London Road and Market Square. Horsham sits on or near the A24 and A29, so getting to you is simple. Other places close to Horsham include Tower Hill (1 mile south-west), Broadbridge Heath (2 miles west), Holbrook (2 miles north), Warnham (2 miles north-west) and Southwater (3 miles south). Larger places within reach include Crawley (7 miles north-east), Haywards Heath (11 miles south-east), Burgess Hill (11 miles south-east), East Grinstead (14 miles east), Broadfield (5 miles east) and Storrington (11 miles south-west). Horsham is one of the larger places we cover in West Sussex.
Around Horsham
Locally, jobs take us to homes and businesses close to Millais School, Warnham Park and Kingslea Primary School, among other places. There’s a railway station in Horsham itself: Horsham station. Other landmarks nearby include Christs Hospital School Museum (2.4 miles south-west) and Horsham Hospital (under half a mile north-west). The countryside around Horsham includes Warnham LNR.
What happens on the day
There is not much for you to do on the day. Show us the job and we will take it from there. The work itself takes a few hours per window, depending on the condition of the joints from start to finish. For homes and businesses in busier parts of Horsham, parking needs a little planning. Let us know about stairs, lifts or shared entrances too.
- We check each window surround and the condition of the joint.
- We rake out the old mastic and clean the joint.
- We fill deep gaps so the new mastic is not too thick.
- We point the joint with sand mastic by hand.
- We finish the mastic to a tidy line.
Getting ready for the visit
- Mention any leaks or damp you’ve noticed
- Tell us about access, such as stairs, a lift or high-level joints
- Let us know about parking restrictions
How to get a quote
Call for a quick quote, or email us if that is easier. Tell us about the joints that need doing and we’ll explain what’s involved before giving you a price.
Advice
Leave it or put it right?
New sash windows are a major, costly change, and in listed buildings it may need consent. Where the frames are in good order, new mastic seals the surround. In a large rental market like Horsham, tired sealant leads to tenant complaints about mould, damp and leaks. Sorting it between tenancies is easier than dealing with it mid-let.
Every job is a little different, so each one gets its own quote. Size, access and the product the joint needs all play a part.
Why us?
- Every job guaranteed for a year
- Arbo and Everbuild products
- Neat joints and a tidy finish
- Approved under the ARBOMaster scheme
See how sealant jobs are priced and our reviews.
Surface by surface
Brick reveals
Gaps between frame and brick let in rain and draughts. New mastic seals the gap.
Period and listed homes
Sand mastic is the like-for-like choice for many period homes. On listed buildings, check with your planning authority first.
Also near Horsham
Other services in Horsham
Questions from Horsham
Do you cover Horsham for sand mastic?
Yes, Horsham is within the area we cover. Our work covers London and the South East. Just call 0345 464 0079 or email us with a few details of the job, and we’ll send you a clear quote.
Do you work for landlords with property near Horsham station?
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’ll give you a fixed price before we start.
Do you do commercial work?
Yes, regularly. We can plan bigger jobs in stages.
What does sand mastic cost?
There’s no set price, as it depends on the job: how much there is, what’s there now, how we reach it and what it needs. We agree the price before any work begins.
Will it make a mess?
Very little: the area around the joints is protected first, and we clear up the old sealant and our materials before we leave.
Can you replace silicone on a period window with sand mastic?
Yes, we do this often. The old silicone has to come out completely so the mastic can sit properly.
Which is right for my windows, sand mastic or modern sealant?
For period timber windows in stone or brick, sand mastic is often the better fit. Modern frames normally suit a flexible sealant.
How long does the job take?
Typically it takes a few hours for a single window, longer for several. Larger jobs naturally take longer, and we will tell you how long to expect.
Honest limits
Sealant is not the answer to every problem, and we’d rather say so up front. Sealant won’t put right:
- Rotten sashes, sills or window boxes (a joiner’s job)
- Sashes that need overhauling
- Decisions on consent for listed homes
If in doubt, call 0345 464 0079 or email us and we’ll say what we think before you book.
What we seal
- Brick reveals
- Timber door frames
- Stone surrounds
- Period & listed homes
- Sash and case windows
- Tenement windows