Oxfordshire · England
Didcot Window Mastic
Specialist window mastic for Didcot: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Gaps between the frame and the inside reveal
- Sealant in the wrong colour for the frame
- Leaking joints at the ends of sills
Window mastic in Didcot
Behind a thin line of old mastic there’s sometimes a deep void. Filling it with sealant alone leaves a joint that cannot move properly, so we fit backing rod to set the right depth. The sealant then grips the two sides it should. If you are dealing with water coming in at the bottom corners of a door and gaps between the frame and the inside reveal, we can put it right.
In a town like Didcot, older houses sit alongside newer estates, with windows of every age. All of them depend on a sound bead of mastic between frame and wall.
You’re covered for a year from the day we finish. If there’s a problem with it, please call 0345 464 0079 or drop us an email.
- Place
- Didcot (OX11)
- Region
- Oxfordshire
- Cover
- One year on every job
- Quote
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
When something else is needed
New sealant can’t fix everything, and we’d rather say so up front. Sealant will not put right:
- A frame that has rotted at the joint
- Broken hinges, locks or handles
- Misting between the panes of a double-glazed unit (that needs a new unit)
If in doubt, call 0345 464 0079 or email us and we’ll say what we think before you book.
Joints and surfaces we work on
- uPVC windows
- Window sills
- Patio & French doors
- Aluminium frames
- Timber windows & doors
- Composite doors
Also near Didcot
Also in Didcot
What we are called out for in Didcot
Some failures date back to when the windows were fitted. Mastic laid onto dusty, damp or crumbling surfaces never bonded as it should, so it comes away long before its time.
Keep an eye out for these signs:
- Cracked sealant at the sill ends
- Mastic that’s falling out in pieces
- Damp patches on the reveal after heavy rain
- Sealant in the wrong colour for the frame
For site and facilities teams at buildings such as Manor Primary School, its window and door frames need their mastic kept sound, just like a home’s.
Before booking anyone
- What insurance they hold
- Which sealant they’ll use, and why
- The length of the guarantee
- What the quote includes, VAT included or not
Keeping the joints in good condition
Once the sealant has cured, a few habits help it last:
- Clean frames with a soft cloth and soapy water
- Check the mastic once a year
- Do not aim a pressure washer at the joints
- Make sure the drainage slots aren’t blocked
Clean the frames with mild soapy water, and keep solvents and harsh chemicals off the joint.
On timber windows, water behind the joint can lead to rot. Once wood has rotted, it needs repair before it can be sealed, so early resealing is worth it.
Why act early in Didcot
Failed mastic isn’t a reason to replace sound windows. If the frames and glass are in good order, resealing the joints is often all that is needed. Problems with the glass or gaskets are for a window company, and we will say so. In Didcot, as anywhere, most leaks start as a small gap in a joint, and early is when they’re cheapest and quickest to sort.
The cost depends on the size of the job, how hard the old material is to remove and how easy the joints are to reach. You will have a clear quote before any work starts, so you know where you stand.
Why book with us
- Tidy, careful work
- Any old sealant cut out fully, not covered over
- 4.9 on Google from 180+ five-star reviews
- White, clear, grey or another colour, product permitting
Read our cost guide and our reviews.
For landlords and businesses
Housing providers, facilities teams and property managers book us too in Didcot and across Oxfordshire. Several sites can be quoted together, and we are fully insured for the work.
Mouldy or split sealant often shows up at the end of a tenancy, and it’s quick to put right between tenancies. We can quote for more than one property at once.
Window mastic in Didcot: local notes
London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. With historic houses such as Brightwell Manor (about 3.4 miles east) nearby, there’s older building stock in the area around Didcot as well as newer homes. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that’s traditional sand mastic.
Letting a property close to Didcot Parkway station? Then renewing tired window mastic between tenants heads off draught and damp complaints. For an older house near a landmark such as Church of All Saints, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Didcot is about 10 miles south of Oxford, in Oxfordshire. Across the OX11 area, we cover window mastic for homes and businesses. Our area takes in 443 places across Oxfordshire, large and small. For nearby work, see our Oxford page.
Here we cover the OX11 postcode area for window mastic. We cover properties on Station Road, Market Place and High Street and the roads around them. Didcot is on the A4130 and B4016, so it’s easy for us to get to with everything needed for window mastic. We also cover Great Western Park (1 mile west), Appleford-on-Thames (2 miles north), Milton (2 miles north-west), Sutton Courtenay (2 miles north-west) and Long Wittenham (3 miles north-east). We also work in nearby towns such as Oxford (10 miles north), Abingdon-on-Thames (5 miles north), Thame (15 miles north-east), Wantage (8 miles west), Grove (8 miles west) and Faringdon (15 miles west). Didcot is one of the larger places we cover in Oxfordshire.
Landmarks near Didcot
Around Didcot, our work takes us to homes and buildings near Didcot Girls' School, The Queens Arms and UTC Oxfordshire and the streets around them. Didcot has its own railway station: Didcot Parkway station. Nearby you will also find Abingdon Community Hospital (4.8 miles north-west) and Brightwell Castle (3.4 miles east). For a walk, there’s Mowbray Fields and Wittenham Clumps.
What we do, step by step
We work through the job in order: protect, prepare, seal, tidy. Typically it takes most of a day for a typical house, less for a few frames and we leave things clean and tidy. In Didcot, parking is rarely complicated, though it helps to know about driveways or restrictions, and mention if the work is upstairs, in a flat or high on the outside.
- We check how each frame can be reached safely.
- All the failed sealant is cut away.
- The surfaces are cleaned and left dry, and primed where the sealant calls for it.
- Deep voids are backed, then the sealant is gunned in.
- We tool the joint so water runs off, then clear up.
Preparing for the visit
- Let us know about earlier repairs to the joints
- Tell us about any water getting in
- Move anything stored near the joints
Get a quote
To get a quote, phone 0345 464 0079 or send us an email and tell us where the job is and what the problem looks like. We will give you a clear price before any work starts.
Read more
Surface by surface
uPVC windows
uPVC expands and contracts noticeably with temperature, so the joint needs a low-modulus sealant that stays flexible. We match white, brown, anthracite grey and black frames.
Composite doors
A composite door normally sits in a plastic outer frame, so its perimeter joint is sealed much like a window. The bead is colour-matched to the frame.
Questions from Didcot
Is there a guarantee on window mastic in Didcot?
All our work, in Didcot and everywhere else, comes with a 12-month guarantee. We’re fully insured, and an ARBOMaster approved applicator.
Do you work for landlords with property near Didcot Parkway station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. Just ring 0345 464 0079 or send us an email with the address and what needs doing, and we will send you a clear quote.
Do you seal inside as well as outside?
Yes. Inside, the joint between frame and plaster is sealed neatly, using a paintable sealant if you want to decorate.
Do you remove the old sealant?
Always. Sealing over the old bead is the commonest cause of early failure, and it’s something we never do.
How long will my window job take?
Allow a few hours for a handful of frames, longer for a whole house. Access and the amount of old mastic make the biggest difference.
Will it make a mess?
Very little: the area around the joints is protected first, and we tidy up before we go.
Which products do you use?
It depends on the joint: sanitary silicone where it gets wet, and sealants suited to movement or weather elsewhere. Brands we use include Arbo and Everbuild.
Where do you work from?
We are a Crawley-based firm. We work across South East England, London and Scotland.