Greater London · England
Window & door mastic in Hounslow, Greater London
Mastic around window and door frames, sills and patio doors for householders, landlords and businesses in Hounslow. ARBOMaster approved applicators, fully insured, with a 12-month guarantee.
- Gaps left after new windows were fitted
- Black, perished sealant on frames
- Leaking joints at the ends of sills
Work for landlords, hotels and businesses
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
If you manage several properties in or around Hounslow, jobs at different addresses can be quoted together. Send us the addresses and the work at each, and photos by email help.
Window mastic in Hounslow
The mastic around a window or door seals the gap between the frame and the wall. Once that seal fails, wind and rain find the gap. The old mastic is removed and the joint resealed with a flexible exterior sealant. We’re often asked to deal with mastic that’s falling out in pieces and untidy mastic left by window fitters, across timber windows & doors, composite doors and window sills.
London has a lot of flats and conversions, where windows are often on upper floors. In a converted house or block, the lease usually says who is responsible for the windows, so it’s worth checking before booking.
A one-year guarantee comes with the work, just as it does everywhere we cover.
- Place
- Hounslow (TW13)
- Wider area
- Greater London
- Guarantee
- One year on every job
- Price
- A clear price before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Your questions about window mastic in Hounslow
Is parking a problem for a job in Hounslow?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
Can you do window mastic in Hounslow?
Yes, Hounslow is within the area we cover. We work across London and the South East. You can call 0345 464 0079 or drop us an email and tell us what needs doing.
What information do you need?
Just the basics: where it is, what you’ve noticed and how we reach it. After that, simply call 0345 464 0079 or send us an email.
Do you hold any approvals?
Yes. We’re ARBOMaster approved, the scheme for applicators of Arbo sealants.
Do you guarantee window mastic?
Yes. All our work carries a 12-month guarantee, and we are ARBOMaster approved applicators.
Can you work on commercial sites?
Yes. We work in offices, washrooms, hotels and other commercial premises. Working times can be discussed when we quote.
Can you seal the gap between the frame and the plaster indoors?
Yes. Outside is the weather seal; inside closes the gap to the plaster. We do one or both.
Are you insured?
Yes. Mr Mastic is fully insured.
Should I try it myself first?
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. All the old material has to come out 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.
How the visit works
You do not need to clear the whole room or building, just the space around the work. Everything nearby is protected, and the job takes a few hours for a few frames, or a day or more for a whole house for a typical job. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. Mention any building rules, key holders or managing agents when you book.
- We start by checking each window and door with you.
- Next the failed sealant is cut away and the joint cleaned.
- Deep gaps are filled with backing rod to set the depth.
- A flexible, weatherproof sealant is applied in a colour to suit the frame.
- We clear up and check every joint is fully closed.
Before we arrive
- Tell us about access, such as stairs, a lift or high-level joints
- Mention any sign-in or site rules at work premises
- Mention any leaks or damp you’ve noticed
Get a quote
Quotes start with a quick conversation. Describe the problem, the location and the size of the job, and we will explain how we’d tackle it. Whenever you’re ready, call 0345 464 0079 or drop us an email.
Read more
Frames and glazing around Hounslow
With historic houses such as Strawberry Hill House (about 4 miles east) nearby, there’s older building stock in the area around Hounslow as well as newer homes. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window. 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.
Hounslow is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. If you live in an older home near Church of St Dunstan, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Hounslow is about 1 mile north of Sunbury-on-Thames, in Greater London. From the centre of Hounslow to the outskirts, window mastic is available for homes and businesses alike. 764 places in Greater London are on our list. There’s also a page for London, roughly 15 miles from Hounslow.
Here we cover the TW13 postcode area for window mastic. We also cover the places around Hounslow: Ashford Common (1 mile south-west), Littleton Common (1 mile south-west), Sunbury-on-Thames (1 mile south), Feltham (1 mile north-east) and Bedfont (1 mile north). Within a short drive, we also cover London (15 miles east), City of Westminster (13 miles north-east), Marylebone (14 miles north-east), Kensington (11 miles north-east), St Pancras (15 miles north-east) and Hampstead (14 miles north-east).
What’s near Hounslow
Typical jobs here are in homes near Sunbury Park, Sunbury Manor School and Sunbury Manor School. For rail, the closest station is Sunbury station, about 0.9 miles south-east. Well-known places in the area include Treaty Centre (3.8 miles north-east) and Ashford Hospital (1.9 miles north-west). For a walk, there’s St Ann's Hill and Staines Reservoirs.
Towns and villages near Hounslow
What else we do in Hounslow
Quotes for window mastic in Hounslow
The price is agreed before any work begins. It takes into account:
- How much there is to do
- How many rooms, windows or areas are involved
- How easy the joints are to reach
- The old material and how stubborn it is
What it costs depends on the amount of work, how hard the old material is to remove and how easy the joints are to reach. You’ll have a clear quote before any work starts.
Helping us quote
When you call or email, it’s useful to know:
- Roughly how big the job is
- If someone has resealed it before
- Pictures of the joints, sent by email
- Any access issues, like height or stairs
Asking for a quote is easy: let us know the job and the location. Photos by email help us understand the job, and we’ll take it from there.
Do you need window mastic in Hounslow?
On timber frames, paint and putty build up around the joint. Old mastic gets painted over and cracks under the paint, and the wood moves with damp as well as heat.
It’s worth asking for a quote if you see:
- Old mastic that has gone black or come away
- Cold air getting in at the frame edge
- Cracked sealant at the sill ends
- Sealant in the wrong colour for the frame
For site and facilities teams at buildings such as Meadhurst Primary School, its window and door frames need their mastic kept sound, just like a home’s.
Comparing quotes
- Are they insured?
- Which sealant they’ll use, and why
- How the joint is cleaned and prepared
- What the quote includes, VAT included or not
What sealant work can’t fix
In fairness, there are a few things sealant won’t fix:
- A sash or casement that won’t close properly
- Rotten timber, which needs a joiner first
- Damp coming through the wall itself rather than the frame joint
If you’re not sure, just call 0345 464 0079 or send us an email and we will give you a straight answer before you book.
Joints and surfaces we work on
- Window sills
- Aluminium frames
- Timber windows & doors
- Patio & French doors
- Composite doors
- uPVC windows
Why deal with it now?
Redecorating is a good moment to renew the mastic. Fresh joints finish the job neatly, and it’s easier while the walls are being worked on anyway. In London conversions, one flat’s bathroom is often above another flat’s ceiling, and a slow leak from a failed seal can end up in the flat below. Dealing with it early is far simpler.
Every job is a little different, so we quote each one individually. Size, access and the product the joint needs all play a part, and we will explain the quote if you ask.
What you get with us
- Neat joints and a tidy finish
- Colour picked to suit the job
- You choose the colour before work begins
- Over 20 years’ experience
Read our cost guide or what customers say.