Surrey · England
Merstham Sand Mastic
Sand mastic for Merstham, by sealant specialists with 20+ years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Mastic worn away on windows facing the weather
- A silicone bead on a sash window that spoils the look
- Gaps between timber frames and stone or brick
About our sand mastic in Merstham
A silicone bead around a sash window can look out of place and does not suit the building. Sand mastic is the traditional choice and we can swap the silicone for it. We work on timber door frames, stone surrounds and sash and case windows, and people most often call us about failed mastic on an exposed elevation and gaps between timber frames and stone or brick.
In a village or hamlet like Merstham, older cottages and farmhouses often have timber windows set in stone or brick. Not every older frame suits a modern silicone bead, so the sealant has to be chosen to suit the building.
Every job comes with our 12-month guarantee, wherever you are in Surrey.
- Where
- Merstham (RH1)
- Wider area
- Surrey
- Cover
- 12 months on all our work
- Quote
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Landlord and commercial work in Merstham
Businesses can book us for washrooms, kitchens, offices and more. On commercial sites, working times can be discussed when we quote.
Failed sealant is one of the commonest items on a check-out report. Several properties can be quoted together.
Nearby places to Merstham
Other services in Merstham
Do you need sand mastic in Merstham?
Paint, silicone or cement used over old mastic causes problems. They do not suit the joint, and they usually need raking out.
The problems people normally mention when they call include:
- Old sand mastic that has cracked, crumbled or fallen out
- Gaps between timber frames and stone or brick
- Gaps round a timber door in stone or brick
- Mastic worn away on windows facing the weather
Rented homes near Merstham station change hands often, and older sash windows in a rental need their mastic kept sound to keep the weather out.
Questions to ask before booking
- What the quote includes, VAT included or not
- Which sealant they’ll use, and why
- Whether they seal over old material or remove it
- Who does the work, and how experienced they are
How the job changes by surface
Period and listed homes
Many older homes were built with sand mastic round the windows. On listed buildings, check with your planning authority first.
Stone surrounds
The stone is treated with care when the old mastic comes out.
Merstham homes and the weather
Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Homes close to Church of St Katharine include some older properties, and the joint between an old wall and a newer frame is usually the first place rain gets in. Managing a site like Merstham Primary School? Then the mastic around its windows and doors needs looking after like any other building’s.
Merstham is about 2 miles north of Redhill, in Surrey. We carry out sand mastic for homes and businesses in Merstham. Across Surrey, we cover 395 places, and Merstham is one of them. For nearby work, see our Crawley page.
Jobs for sand mastic in RH1 works the same way as everywhere else we cover. Streets in the area include London Road North, Shepherd's Hill and Church Hill, and we cover them all. We also cover the places around Merstham: South Merstham (1 mile south), Gatton (1 mile south-west), Holmethorpe (1 mile south), Hooley (2 miles north) and Netherne on-the-Hill (2 miles north). Further out, we also cover Epsom (7 miles north-west), Horley (6 miles south), Ewell (7 miles north-west), Reigate (3 miles south-west), Walton-on-Thames (14 miles north-west) and Caterham (3 miles north-east).
What’s near Merstham
In Merstham, that means homes and buildings near Merstham Park School, Nutfield Marshes and East Surrey College, among other places. For rail, the closest station is Merstham station, roughly 0.5 miles south. Well-known places in the area include Surrey Fire Museum (2.8 miles south-west) and Bletchingley Castle (2.8 miles south-east). Green spaces nearby include South London Downs National Nature Reserve and Colley Hill.
How we quote for sand mastic
For a quick quote, just ask. What matters most is:
- How much old sealant there is and how hard it is to remove
- Any mould that needs treating
- The type of sealant required
- The number and length of the joints
What you pay reflects the work, not a rough estimate. That is why we ask about the job first and agree the price before starting.
What we need to know
You don’t need to know the technical terms. Just tell us:
- What’s wrong with the joints now
- Access, such as stairs, a lift or height
- The rough size of the job
- Where the property is
We don’t publish a price list. Instead, your job gets its own clear quote. To arrange one, phone 0345 464 0079 or drop us an email.
FAQs for Merstham
Do you cover Merstham for sand mastic?
Yes. Our work covers London and the South East, and Merstham is part of that. You can phone 0345 464 0079 or email us and let us know what needs doing, and we will give you a clear price.
I let a flat near Merstham station. Can you help?
Yes, landlords and agents are among the people we work for. Just call 0345 464 0079 or email us with the address and what needs doing, and we’ll give you a clear quote.
Are you fully insured?
Yes, we are fully insured for every job we do.
Can you quote for more than one area?
Yes. Tell us about everything you’d like done and you’ll get one quote.
Is it possible to paint over sand mastic?
The usual advice is to leave sand mastic unpainted. Ask us before you decorate around it and we’ll talk you through it.
How long does sand mastic take to harden?
The surface skins quite quickly, then hardens over a longer period. The weather and joint depth both affect it.
Will you leave a mess?
No. The area is protected while we work and cleaned up afterwards.
What sealant do you use?
The product depends on the job: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. Brands we use include Arbo and Everbuild.
Honest limits
Some problems need a builder, plumber or other trade rather than us:
- Planning or listed building consent (your local planning authority decides)
- Sash cords, weights and draught-proofing of the sashes
- Masonry that needs repairing
Not sure which it is? You can call 0345 464 0079 or drop us an email and we’ll tell you honestly before booking.
Surfaces we seal
- Sash and case windows
- Stone surrounds
- Brick reveals
- Tenement windows
- Period & listed homes
- Timber door frames
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.
A DIY attempt does not rule out a professional job. We cut it out and start again, so tell us about it when you ask for a quote.
How the visit works
Good joint work is mostly preparation, so that’s where we spend the time. Every joint is cleaned and dried before new material goes in. In total, it usually takes a few hours for a single window, longer for several. Somewhere as small as Merstham, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- First, we look at the surrounds with you and agree what needs doing.
- The loose and crumbling mastic is raked out and the joint cleaned.
- We pack any deep gaps so the mastic sits at the right depth.
- The mastic is mixed, pressed into the joint by hand and shaped.
- The mastic is finished to sit tidily against the stone or brick.
Preparing for the visit
- Clear items away from the joints we’re working on
- Let us know about stairs, lifts or work at height
- Plan for the work area to be out of bounds to pets and children
Getting a quote
We quote each job on its own, so the first step is telling us about yours. Just call 0345 464 0079 or drop us an email with the details, and photos are welcome.