Surrey · England
Window & door mastic in Sunbury-on-Thames, Surrey
Mastic around window and door frames, sills and patio doors for homes and businesses in Sunbury-on-Thames and across Surrey. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Old mastic that has gone black or come away
- Cracked sealant at the sill ends
- Draughty joints inside around the window
How the visit works
Every visit runs the same way: we check the joints, protect the area around them, do the work and clear up. It normally takes a few hours for a handful of frames, longer for a whole house. A visit in Sunbury-on-Thames needs access to the work and a place to park close by. For outside work, let us know about side access, gates and any upper-floor joints.
- First, we confirm safe access to each frame.
- All the failed sealant is cut away, along with any loose debris.
- Frame and wall are cleaned and must be dry before sealing, and primed where the sealant calls for it.
- Backing rod fills deep voids and the sealant goes in on top.
- We tool the joint so water runs off, then clear up.
Getting ready for the visit
- Keep pets and children clear of the area while we work
- Where the joints are inside, avoid wetting them before we arrive
- Mention any parking rules near the property
Getting a quote
For window mastic in Sunbury-on-Thames, ring 0345 464 0079 or email us. Tell us what the problem is and where, and we will agree the price before any work begins.
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About our window mastic in Sunbury-on-Thames
Every window and door frame has a gap around it, and mastic is what closes it. When it cracks, hardens or pulls away, draughts and rain get in. The old mastic is removed and the joint resealed with a flexible exterior sealant. We work on patio & French doors, timber windows & doors and window sills, and people most often call us about draughts coming in around windows and doors and hard, cracked sealant around windows.
Walls in Sunbury-on-Thames that face the prevailing wind take the most weather, so the mastic there tends to fail first. Checking every frame, not just the obvious one, is time well spent.
We guarantee the work for a year. If something is not right with it in that time, tell us and we’ll put it right.
- Where
- Sunbury-on-Thames (TW16)
- Wider area
- Surrey
- Cover
- One year on every job
- Quotes
- A clear price before work begins
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Do you need window mastic in Sunbury-on-Thames?
Some failures date back to when the windows were fitted. Sealant run over dust, wet brick or loose mortar never bonded as it should, so it comes away long before its time.
These are the problems we’re asked about most:
- White mastic on grey or black frames
- Cracked internal joints between frame and plaster
- Old mastic that has gone black or come away
- Gaps left after new windows were fitted
For landlords with property near Sunbury station, renewing tired window mastic between tenants heads off draught and damp complaints.
Questions to ask before you book
- Whether VAT is included
- How the joint is cleaned and prepared
- Whether they’re fully insured
- When the joint can take water or movement
For landlords and businesses
In hotels, rooms out of use cost money, so we plan the work room by room around your bookings where we can. We’ve worked in hotels as well as homes and businesses.
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements.
Different surfaces, different methods
Patio & French doors
The joints around patio doors run a long way, top, sides and threshold. Most leaks start at the bottom corners, so we pay close attention there.
Window sills
Every drop off the glass ends up on the sill, so the sill ends and the joint under the frame are vital. They’re cut out and resealed with exterior sealant.
Places near Sunbury-on-Thames
What else we do in Sunbury-on-Thames
What happens if it’s left?
A cracked joint around a frame lets rain into the wall. Over time that can mean damp patches, damaged plaster and rotting timber. A reseal is a much smaller job. Black mould and gaps in sealant do not fix themselves, and in a busy home in Sunbury-on-Thames they get worse with every use. Replacing the sealant now is the simplest fix.
A failed joint rarely gets cheaper to fix by waiting, as water and mould keep getting in. If you are unsure, ring 0345 464 0079 or email us and we’ll give you an honest view and a quote.
Why Sunbury-on-Thames customers choose us
- Colour agreed with you before any work starts
- Homes, businesses and hotels
- One-year guarantee on every job
- Fully insured
Read what affects the cost and what customers say.
Aftercare tips
Good habits help new joints last longer. A few tips:
- Keep paint and stain on wooden frames in good order
- Don’t paint over the silicone
- Keep jet washers away from the mastic
- Ventilate rooms so frames don’t stay wet inside
A yearly look round the frames is enough. Small splits are simple to catch before they leak, and if anything looks wrong, just call 0345 464 0079 or send us an email.
Signs to watch for: split or missing mastic, gaps, damp patches inside or black mould on the reveal. Any of these is worth a call.
Sunbury-on-Thames homes and the weather
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. With historic houses such as Hampton Court Palace (about 3.5 miles east) nearby, there’s older building stock in the area around Sunbury-on-Thames 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.
For site and facilities teams at buildings such as St Ignatius RC Primary School, its window and door frames need their mastic kept sound, just like a home’s. If you live in an older home near St Saviour, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Sunbury-on-Thames is about 7 miles south of Hayes, in Surrey. Wherever you are in the TW16 postcode area, we can carry out window mastic at your property. Our Surrey coverage runs to 395 places, and Sunbury-on-Thames is one of them. Our London page covers work nearby (15 miles or so).
All of TW16 is covered for window mastic, from the main roads to the quietest streets. Window mastic is available to properties on Station Road, The Ridings and Ravenscourt. Main roads around Sunbury-on-Thames include the A244 and A308. We also cover the places around Sunbury-on-Thames: Upper Halliford (1 mile south-west), Charlton (1 mile west), Ashford Common (1 mile north-west), Hounslow (1 mile north) and Littleton Common (1 mile west). Larger places within reach include Guildford (13 miles south-west), Woking (10 miles south-west), Camberley (15 miles south-west), Epsom (8 miles south-east), Ewell (8 miles south-east) and Egham (6 miles west).
Around Sunbury-on-Thames
Locally, jobs take us to homes and businesses close to Sunbury Manor School, The Three Fishes Public House and Sunbury Park and the streets around them. There’s a railway station in Sunbury-on-Thames itself: Sunbury station. Well-known places in the area include Kempton Steam Museum (1 mile north-east) and No. 2 New Zealand General Hospital (2 miles south). Green spaces nearby include St Ann's Hill and Kempton Park Reservoirs.
FAQs for Sunbury-on-Thames
Do you work for landlords with property near Sunbury station?
Yes, landlords and agents are among the people we work for, and several properties can go on one quote. You can call 0345 464 0079 or drop us an email with the details for a clear quote.
What guarantee comes with window mastic in Sunbury-on-Thames?
Every job comes with our one-year guarantee, wherever it is. We are also fully insured and ARBOMaster approved.
Can I do it myself?
Some simple jobs can be done by a careful DIYer. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Can you reach windows above the ground floor?
Yes, as long as they can be reached safely. Let us know about access when you ask for a quote so we can plan the job.
Do you do commercial work?
Yes, regularly. Larger jobs can be planned room by room or area by area.
Can you do the inside joint as well?
Yes. Indoors, we seal between the frame and the plaster or reveal, using a paintable sealant if you want to decorate.
Does someone need to be in?
Access is agreed with you when the job is booked. For inside work, that normally means someone being in.
Do you take out the old sealant first?
Yes, always, and completely. New sealant won’t bond properly to old, so any old material comes out before anything new goes in.
Can I do it myself?
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions, then guaranteed for a year.
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.