Greater London · England
Window & door mastic in Feltham, Greater London
We cover Feltham for mastic around window and door frames, sills and patio doors. Old sealant removed completely, joints prepared properly and a one-year guarantee.
- Rushed sealant from a window installation
- Sealant in the wrong colour for the frame
- Damp patches on the reveal after heavy rain
Window mastic in Feltham
If you can feel air around a shut window, the gap is often at the frame. Resealing that joint can make a room feel noticeably less draughty. If the draught is through the window seals instead, we will tell you. We’re often asked to deal with white mastic on grey or black frames and gaps left after new windows were fitted, across window sills, timber windows & doors and patio & French doors.
From mansion-block windows to modern glazing in new flats, London has every kind of frame. The mastic around them dries out and cracks with age, letting in draughts and water.
Our work is backed for twelve months, in Feltham and everywhere else we cover.
- Where
- Feltham (TW14, TW13)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Price
- Quoted before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
What window mastic looks like in Feltham
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. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window. The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Feltham is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. Homes close to Christ Church include some older properties, and the joint between an old wall and a newer frame is generally the first place rain gets in.
Feltham is about 6 miles south-west of Ealing, in Greater London. Wherever you are in the TW14 postcode area, we cover window mastic for homes and businesses. We cover 764 towns and villages across Greater London. London is on our list too, about 14 miles from Feltham.
We cover every part of TW14 and TW13 for window mastic and the streets around it. If you need window mastic at a property on High Street, Railway Terrace and Sandycombe Road or a nearby road, our applicators can take on the job. Feltham is on the A244 and B377, so it’s easy for us to get to with everything needed for window mastic. 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). Larger places within reach include 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).
What’s near Feltham
Locally, jobs take us to homes and businesses close to Hounslow Heath, Moon On The Square pub and Rivers Academy West London. Feltham has its own railway station: Feltham station. Well-known places in the area include Hounslow Hospital (2.3 miles north-east) and Kempton Steam Museum (1.6 miles south). Open spaces near Feltham include Richmond Hill and Pevensey Road Nature Reserve.
Signs you need window mastic in Feltham
Mastic ages in the weather. UV light hardens the outside of the bead, until it loses its stretch and starts to crack.
Most people get in touch after spotting one of these:
- Rain getting in at the frame or under the sill
- A bead that doesn’t match the frame
- Black, perished sealant on frames
- Cracked internal joints between frame and plaster
For landlords with property near Feltham station, renewing tired window mastic between tenants heads off draught and damp complaints.
What your quote should include
- Which colour the sealant will be
- How the joint is cleaned and prepared
- When the joint can take water or movement
- Is VAT in the price?
How it works
On the day, there’s very little for you to do. Show us the job and we’ll take it from there. The job generally takes a morning for a couple of windows and a door, including the tidy-up. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- We check each frame and agree which ones need doing.
- We remove the old mastic and clean the frame and the wall.
- Deep gaps are filled with backing rod to set the depth.
- A flexible, weatherproof sealant is applied in a colour to suit the frame.
- Every joint is checked before we leave.
Getting ready for the visit
- Move anything stored near the joints
- Mention any parking rules near the property
- Where the joints are inside, avoid wetting them before we arrive
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’ll explain what’s involved.
Advice
When something else is needed
Some problems need a builder, plumber or other trade rather than us:
- Misting between the panes of a double-glazed unit (that needs a new unit)
- Soft or decayed wood in the frame
- Faulty window hardware
Not sure which it is? You can ring 0345 464 0079 or drop us an email and we’ll tell you honestly.
Where we work in Feltham
- Window sills
- Composite doors
- Timber windows & doors
- Patio & French doors
- Aluminium frames
- uPVC windows
Aftercare tips
So the new joints stay in good condition:
- Wash the frames with mild soapy water
- Walk round the house once a year and look at the joints
- Keep paint off silicone joints
- Keep jet washers away from the mastic
Most silicone sealants won’t take paint, so if you’re planning to paint the frames or walls, tell us beforehand. There are paintable sealants for joints that need it.
A small gap around a frame only grows. As old mastic keeps shrinking, the gap widens, and heat escapes around the frame. Resealing closes it.
Should I try it myself first?
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
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.
Questions from Feltham
Is parking a problem for a job in Feltham?
In much of London, parking needs planning: a visitor permit or a nearby bay makes the day run more smoothly, so mention what’s available when you book.
Do you work for landlords with property near Feltham station?
Yes. We work for landlords and agents as well as householders. Just call 0345 464 0079 or send us an email with the address and what needs doing, and we’ll send you a clear quote.
Do you come to Feltham?
We do. Our applicators work in Feltham.
What should I tell you?
The location, the problem and the rough size of the job. If you can, email a few photos.
Do you seal inside as well as outside?
Yes. Draughts often come through the inside gap too, so it can be worth sealing both.
How long before the joint can be used?
Most sealants are touch-dry well before they’re fully cured. We will tell you how long to leave the joint.
Can resealing stop a draught around my window?
If the draught is coming in around the frame, yes. If it’s coming through the window seals, we will tell you.
Can you do upstairs windows?
Normally, yes. Access is planned before we start, so mention the height and anything in the way.
What affects the cost of window mastic
Every job gets its own quote. These are the things that affect it:
- The number of rooms or windows
- Access and height
- The size of the job
- Whether old sealant or filler has to be cut out
The cost reflects the work involved, not a rough estimate. That’s why we ask about the job first and agree the price before starting.
Asking for a quote
When you call or email, these details help:
- Roughly how big the job is
- A few pictures by email, if you can
- Access, such as stairs, a lift or height
- If it’s domestic, commercial or a hotel
We quote each job on its own. Simply phone 0345 464 0079 or send us an email and describe the job, and photos are welcome.
Also in Feltham
What the job involves on each surface
Patio & French doors
Not every patio door leak is a mastic problem: blocked drain slots, worn brush seals and threshold details can let water in too. We check before we reseal.
Window sills
The end joints of a sill tend to fail before the rest. A tight seal at each end keeps rain out of the wall.