Oxfordshire · England
Sand mastic for sash & case windows in Farnborough, Oxfordshire
Our applicators work in Farnborough on traditional burnt sand mastic around sash and case windows and doors in stone and brick. Old sealant removed completely, joints prepared properly and a 12-month guarantee.
- Patchy fillers round a sash window
- Open joints round the window box
- Mastic worn away on windows facing the weather
About our sand mastic in Farnborough
Sand mastic has long been used to fill the joint between timber frames and masonry. It’s made from sand and a linseed-oil-based binder and built up by hand. On older homes, it suits the building far better than silicone. We are often asked to deal with patchy fillers round a sash window and tired mastic found when preparing windows for paint, across timber door frames, stone surrounds and brick reveals.
Around Farnborough, many homes face open ground, so their windows and doors take the full weather. Exposed frames and sills lose their mastic sooner than sheltered ones.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we will put it right.
- Location
- Farnborough (OX12)
- Wider area
- Oxfordshire
- Cover
- A year, on every job
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
What sealant work cannot fix
To be straight with you, some problems need a different trade:
- Broken panes
- Masonry that needs repairing
- Whether work needs listed building consent
If you are not sure, just phone 0345 464 0079 or send us an email and we will give you a straight answer.
Joints and surfaces we work on
- Sash and case windows
- Tenement windows
- Period & listed homes
- Stone surrounds
- Brick reveals
- Timber door frames
Windows and doors in Farnborough
Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
For an older house near a landmark such as Church of All Saints, the joint between an old wall and a newer frame is normally the first place rain gets in.
Farnborough is about 4 miles south-east of Wantage, in Oxfordshire. Wherever you are in the OX12 postcode area, we can carry out sand mastic at your property. Our area takes in 443 places across Oxfordshire. Oxford is on our list too, about 16 miles from Farnborough.
Our applicators cover all of the OX12 postcode area for sand mastic and the streets around it. Close by, we work in Catmore (2 miles south-east), Brightwalton (2 miles south), Brightwalton Green (2 miles south), West Ilsley (3 miles east) and Stanmore (3 miles south-east). We also work in nearby towns such as Didcot (8 miles north-east), Abingdon-on-Thames (11 miles north), Wantage (4 miles north-west), Grove (6 miles north-west), Faringdon (12 miles north-west) and Benson (13 miles north-east).
What’s near Farnborough
Nearby you’ll also find Atlas Computer Laboratory (3.8 miles north-east). Not far away are Letcombe Valley and Chain Hill.
Common problems we fix in Farnborough
Timber frames move with the seasons. The movement cracks the mastic little by little.
People generally contact us after spotting one of these:
- Mastic round period door frames that has failed
- Wind and rain getting in round a sash window
- Gaps where the frame meets the masonry
- Mastic dropping out of the joint
In and around Farnborough, as anywhere, good sand mastic starts with a clean, dry, properly prepared joint.
What to look for in a quote
- What product goes in the joint
- Is VAT in the price?
- What happens if they find a problem under the old sealant
- Which colour the sealant will be
Looking after it afterwards
Good habits help new joints last longer. A few tips:
- Keep sills and gutters clear so water drains away
- Avoid heavy scraping on the mastic joint
- Don’t paint over the new mastic
- Do not run silicone over sand mastic
Keep gutters and sills clear so water runs away from the surround. Constant wetting wears the mastic faster.
Good mastic helps keep the frame dry. Once it fails, water can sit against the timber and timber that stays wet can rot.
How it works
The work is kept neat and contained to the area we are working on. The job normally takes a few hours per window, depending on the condition of the joints. In a small place like Farnborough, access is normally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We check the window surrounds and agree which joints need renewing.
- 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.
- We mix the sand mastic and apply it by hand, shaping it to the joint.
- The mastic is finished to sit tidily against the stone or brick.
Getting ready for the visit
- Mention any parking rules near the property
- Let us know about earlier repairs to the joints
- For indoor joints, keep the area dry beforehand if you can
Ask for a quote
For a quick quote, get us on the phone, or send an email if you’d rather. Describe what needs sealing and we will talk you through the work and send you a clear quote.
Related advice
DIY versus a professional finish
If you do try it yourself, take your time over the preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
Sealing over old silicone is the commonest DIY error. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
Surface by surface
Sash and case windows
The box of a sash and case window sits in the stone or brick opening. The gap round it is pointed with sand mastic.
Tenement and terrace windows
Rows of sash windows on tenements and terraces often need renewing together. We can do one window or several.
Common questions in Farnborough
Is sand mastic in Farnborough guaranteed?
All our work, in Farnborough and everywhere else, comes with a 12-month guarantee. We are also fully insured and ARBOMaster approved.
Do you cover Farnborough for sand mastic?
Yes, Farnborough is within the area we cover. We work across London and the South East. You can ring 0345 464 0079 or drop us an email and let us know what needs doing.
How long does sand mastic take?
A typical job takes anything from a few hours to a full day, depending on how many windows, including preparation and clearing up. Your quote will say how long we expect yours to take.
Can you do several jobs on one visit?
Yes. More than one area can be quoted together.
Where is Mr Mastic based?
Our base is in Crawley, and we cover South East England, London and all of Scotland.
Can sand mastic be painted?
Sand mastic is normally left unpainted, which is what traditional guidance recommends. Talk to us before any painting near it.
What exactly is sand mastic?
It’s a mix of sand and a linseed-oil-based binder. It’s built up in the joint by hand and finished to sit neatly against the masonry.
Which is right for my windows, sand mastic or modern sealant?
We will help you decide. Sand mastic suits many period homes, and modern sealants suit newer frames.
Nearby places to Farnborough
Also in Farnborough
Quotes for sand mastic in Farnborough
The quote reflects the job in front of us. We take into account:
- How much old sealant there is and how hard it is to remove
- Mould in or behind the old joints
- The amount of work
- Working hours on commercial sites
Some things make a job bigger or smaller: the old material and how easily it comes out, any mould to treat, and whether we need extra access for height. Your quote takes all of that into account.
What we need to know
What to tell us when you ask for a quote:
- If it’s domestic, commercial or a hotel
- Access, such as stairs, a lift or height
- Pictures of the joints, sent by email
- If someone has resealed it before
Asking for a quote is easy: let us know the job and the location and its rough size. Photos by email help us understand the job, and we will take it from there.