Greater London · England
Sand mastic for sash & case windows in Feltham, Greater London
Specialist sand mastic for Feltham: careful preparation, the right product and tidy work. Call for a quick quote.
- Crumbling sand mastic round a window
- Cement or filler used on old window joints that has cracked
- Open joints round the window box
About our sand mastic in Feltham
Traditional burnt sand mastic that sits naturally against stone and brick. It’s a good fit for period properties, where modern sealant can look out of place. If you’re dealing with cement or filler used on old window joints that has cracked and gaps where the frame meets the masonry, we can put it right.
Many London homes are flats, with windows high above the street. In a converted house or block, the lease normally says who is responsible for the windows, so it’s worth checking before booking.
The work is guaranteed for twelve months. If something isn’t right with it in that time, tell us and we will put it right.
- Place
- Feltham (TW14, TW13)
- Wider area
- Greater London
- Guarantee
- A year, on every job
- Quotes
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Why it’s worth doing now in Feltham
Cement-based fillers and modern sealants do not always suit a period surround. Sand mastic matches what was there and that can be important for listed homes. In a London flat, a failed joint rarely stays your problem alone: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
There are no prices on our website, because the cost depends so much on the job itself. For a quick quote, please call 0345 464 0079 or email us.
What you get with us
- We leave the area clean and tidy
- Full insurance on every job
- ARBOMaster approved applicator
- 20+ years of sealant experience
Take a look at how sealant jobs are priced and what customers say.
How it works
When we arrive, we look over the joints with you first, so you know exactly what we’re doing. Surfaces next to the work are protected before any work begins. Most jobs take a few hours for a single window, longer for several. For a job in Feltham, parking and access are the things to plan: let us know about parking, the floor we’ll be working on and any lift or shared entrance.
- Each surround is checked first.
- We rake out the old mastic and clean the joint.
- We fill deep gaps so the new mastic isn’t too thick.
- We point the joint with sand mastic by hand.
- The finish is dressed neatly.
How to prepare
- Mention any parking rules near the property
- For indoor joints, keep the area dry beforehand if you can
- Keep pets and children clear of the area while we work
How to get a quote
There’s no standard price list, as no two jobs are quite the same. Instead, we give you a clear quote for your job. To get started, phone 0345 464 0079 or send us an email.
Related advice
Other services in Feltham
FAQs for Feltham
Can you do sand mastic in Feltham?
Yes. Our work covers London and the South East, and Feltham is part of that. Just call 0345 464 0079 or drop us an email with a few details of the job.
Is parking an issue for sand mastic in Feltham?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. The visit is then planned around what’s available.
Do I have to be there?
If the work is inside, we need someone to let us in. After that, you can carry on with your day.
Is it possible to take out silicone and use sand mastic instead?
Often, yes. Once the silicone is out and the joint prepared, sand mastic is applied by hand.
Do you offer different sealant colours?
Most of the time, yes. We’ll explain which colours are available and agree one before we start.
Is it OK to seal over old sealant?
No. New silicone will not bond to old silicone, and anything trapped underneath, including mould and water, stays there. It all has to come out first.
Can sand mastic be painted?
The usual advice is to leave sand mastic unpainted. If you’re redecorating the window, ask us first and we’ll talk you through it.
Will the old sealant be removed?
Yes, always, and completely. New silicone doesn’t stick to old silicone, so any old material comes out before anything new goes in.
Landlords, agents and businesses in Feltham
Mouldy or split sealant often shows up at the end of a tenancy, and it’s easy to sort out between tenants. Several properties can go on one quote.
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance that we can handle for you.
Signs you need sand mastic in Feltham
Rain on the window surround works into any crack and pushes it out. Windows facing the weather tend to go first.
The most common problems we see are:
- Mastic worn away on windows facing the weather
- Cracked mastic round a front door frame
- Draughty sash windows at the surround
- A silicone bead on a sash window that spoils the look
Letting a property close to Feltham station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about.
Questions to ask before booking
- What preparation is included
- Are they insured?
- What happens if the job turns out different
- Whether the sealant suits the joint
What sealant work cannot fix
Sealant isn’t the answer to every problem, and we will tell you before any work starts. Sealant won’t put right:
- Broken panes
- Decayed frames that need repair
- Decisions on consent for listed homes
If in doubt, ring 0345 464 0079 or drop us an email and we’ll say what we think.
Joints and surfaces we work on
- Timber door frames
- Stone surrounds
- Tenement windows
- Period & listed homes
- Brick reveals
- Sash and case windows
How the job changes by surface
Stone surrounds
We take care not to mark the stone when the old mastic comes out.
Tenement and terrace windows
In shared buildings, the windows may be part of a wider repair so it’s worth checking responsibilities.
What affects the cost of sand mastic
Your quote is based on your job. We look at:
- Whether there’s mould to deal with
- The size of the job
- When we can work, for business premises
- Whether the work is at height
The cost reflects the work involved, not a rough estimate. That is why we ask a few questions first and give you a clear price before we start.
What we need to know
You don’t need to know the technical terms. Just tell us:
- If it’s domestic, commercial or a hotel
- How many joints, rooms or windows are involved
- Pictures of the joints, sent by email
- Any previous sealing or DIY work
For a quick quote, get us on the phone, or send an email if you’d rather. Tell us about the joints that need doing and we will explain what’s involved.
Sand mastic in Feltham: local notes
Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. Historic houses like Strawberry Hill House (about 3.5 miles east) are a reminder that the area around Feltham has older buildings as well as new. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic.
Schools such as St Lawrence Catholic Primary School are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages. Feltham is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Feltham is about 6 miles south-west of Ealing, in Greater London. If you need sand mastic in Feltham, please ring 0345 464 0079 or send us an email for a quick quote. We cover Greater London from our Crawley base, Feltham included. Feltham is one of 764 places in Greater London where we work. Our London page covers work nearby (14 miles or so).
Work in TW14 and TW13 works the same way as everywhere else we cover. You will find streets such as High Street, Railway Terrace and Sandycombe Road, all of which we cover. You’ll find Feltham on the A244 and B377, so it’s easy for us to get to. Other places close to Feltham include Bedfont (1 mile west), Hounslow (1 mile south-west), Hatton (1 mile north), Ashford Common (2 miles south-west) and Cranford (2 miles north). We also work in nearby towns such as London (14 miles east), City of Westminster (12 miles east), Marylebone (12 miles north-east), Kensington (10 miles east), St Pancras (14 miles north-east) and Shoreditch (15 miles east).
Around Feltham
In Feltham, that means homes and buildings near Hounslow Heath, Moon On The Square pub and Rivers Academy West London. There’s a railway station in Feltham itself: Feltham station. A little further out are Hounslow Hospital (2.3 miles north-east) and Kempton Steam Museum (1.6 miles south). The countryside around Feltham includes Richmond Hill and Pevensey Road Nature Reserve.