East Sussex · England
Sand mastic for sash & case windows in Horam, East Sussex
Professional sand mastic in and around Horam, with every bit of old sealant taken out first.
- Failed mastic on an exposed elevation
- Mastic round period door frames that has failed
- Draughts and rain around sash boxes
Horam questions
Is Horam in your area for sand mastic?
Yes. Our work covers London and the South East, and Horam is part of that. Just phone 0345 464 0079 or drop us an email with a few details of the job, and we will give you a clear price.
Is sand mastic in Horam guaranteed?
All our work, in Horam and everywhere else, comes with a 12-month guarantee. We are also fully insured and ARBOMaster approved.
Do you hold any approvals?
Yes. We hold ARBOMaster approved applicator status, and we are fully insured.
Is it OK to seal over old sealant?
No, and we never do. It can look neat for a few weeks, but the new layer lifts away from the old one. The old sealant has to come out completely.
Can I choose the sealant colour?
We will suggest a colour to suit the surroundings, from white and clear to greys and other shades. The choice depends on the product the joint needs.
Is sand mastic better than silicone for my windows?
For period timber windows in stone or brick, sand mastic is often the better fit. Modern frames normally suit a flexible sealant.
Are you insured?
Yes. We are fully insured.
Where is Mr Mastic based?
Our base is Crawley. We work across South East England, London and Scotland.
How we handle sand mastic in Horam
Fresh sand mastic forms a skin quite soon but full hardening takes longer. Traditional guidance is not to paint over it, so ask us before you decorate. Typical jobs include gaps where the frame meets the masonry and cracked mastic round a front door frame, across sash and case windows, tenement windows and timber door frames.
Outdoor sealant needs dry, clean surfaces, so work on frames around Horam is planned for dry weather. Tell us about access to every side of the house, including upper-floor windows.
All our work is covered by our 12-month guarantee.
- Location
- Horam (TN21)
- Wider area
- East Sussex
- Guarantee
- 12 months on all our work
- Price
- A clear quote up front
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Different surfaces, different methods
Brick reveals
An open joint at a brick reveal lets weather in. New mastic seals the gap.
Stone surrounds
Stone openings are rarely perfectly straight, so the gap is not the same all the way round. Sand mastic is shaped by hand to suit.
Keeping the joints in good condition
A little care helps the new joints last. We recommend:
- Check with your local planning authority if your home is listed
- Ask a joiner to look at soft timber first
- Inspect the joints round the windows every year or so
- Do not paint over the new mastic
Do not run silicone over the new mastic. If anything cracks, get it looked at rather than patching it.
Once mastic starts to crumble, rain gets in. It can soak into the frame and the surrounding masonry so early renewal protects both.
Horam homes and the weather
London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. Historic houses like Horselunges Manor (about 3.2 miles south) are a reminder that the area around Horam has older buildings as well as new. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window.
Schools such as Maynards Green Community Primary School are buildings too, and the mastic around its windows and doors needs looking after like any other building’s.
Horam is about 5 miles north of Hailsham, in East Sussex. Every kind of property in Horam is covered for sand mastic, old or new, large or small. The work is guaranteed for a year. Our East Sussex coverage runs to 289 places, Horam among them. For nearby work, see our Brighton page.
Every address in TN21 is covered for sand mastic, from the main roads to the quietest streets. Local streets include Little London Road, Toll Wood Road and Beauford Road, all of which we cover. If you’re just outside Horam, we cover Burlow (1 mile south-west), Vines Cross (1 mile east), Maynard's Green (1 mile north), Lions Green (1 mile north-west) and Warbleton (2 miles east). Larger places within reach include Eastbourne (10 miles south), Hastings (15 miles east), Bexhill-on-Sea (11 miles south-east), Seaford (12 miles south-west), Lewes (11 miles west) and Hailsham (5 miles south).
Near you in Horam
Typical jobs here are in homes near Horam Inn and the streets around them. Other landmarks nearby include Sussex Farm Museum (within half a mile north-west) and Hellingly Hospital Railway (3.1 miles south). Open spaces near Horam include Selwyns Wood.
DIY sealant or a professional job?
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, and the work is guaranteed for a year.
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
When it is not the sealant
Sealant is not the answer to every problem, and we’d rather say so up front. It won’t solve:
- Decisions on consent for listed homes
- Broken panes
- Decayed frames that need repair
If you’re not sure, just phone 0345 464 0079 or send us an email and we’ll give you a straight answer before you book.
What we seal
- Timber door frames
- Sash and case windows
- Period & listed homes
- Tenement windows
- Stone surrounds
- Brick reveals
Other services in Horam
Why deal with it now?
If you’re redecorating, renew the mastic first. Painting over failed mastic does not seal it and traditional guidance is to leave the new mastic unpainted. Where a wall is exposed, as many are in small places like Horam, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
The cost depends on the amount of work, how hard the old material is to remove and how easy the joints are to reach. We give a clear quote before any work starts.
What you get with us
- An ARBOMaster approved applicator
- Any old sealant cut out fully, not covered over
- We leave the area clean and tidy
- Anti-fungal silicone where joints get wet
See our cost guide or what customers say.
How it works
There is not much for you to do on the day. Show us the job and we’ll take it from there. The job generally takes anything from a few hours to a full day, depending on how many windows. For a village or hamlet like Horam, the journey is planned in advance: let us know about lanes, gates and parking. We bring what the job needs, so it can be finished in one trip where possible.
- 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.
- New sand mastic is applied and shaped by hand.
- The finish is dressed neatly.
Preparing for the visit
- Mention any sign-in or site rules at work premises
- Tell us about any previous sealing or DIY attempts
- Try not to wet indoor joints just before the visit
How to get a quote
We quote each job on its own. Simply call 0345 464 0079 or email us and describe the job.
Advice
Common problems we fix in Horam
Rain on the window surround works into any crack and loosens it further. Windows facing the weather tend to go first.
If you can see any of these, it’s time to have the joints looked at:
- A silicone bead on a sash window that spoils the look
- Wind and rain getting in round a sash window
- Crumbling sand mastic round a window
- Cement or filler used on old window joints that has cracked
In the older streets around Christ Church, the joint between an old wall and a newer frame is usually the first place rain gets in.
What your quote should include
- What happens if they find a problem under the old sealant
- How the colour is chosen
- The length of the guarantee
- Who does the work, and how experienced they are