Essex · England
Dedham Window Mastic
Mastic around window and door frames, sills and patio doors for homes and businesses in Dedham and across Essex. ARBOMaster approved applicators, fully insured, with a one-year guarantee.
- Leaking joints at the ends of sills
- Gaps left after new windows were fitted
- A bead that doesn’t match the frame
Surface by surface
uPVC windows
The frame is cleaned with a product that won’t harm the plastic, then the sealant goes in between frame and wall.
Window sills
Stone and concrete sills have their own joints, including the one between the sill and the frame above. Those are sealed with a product suited to stone or concrete.
How we handle window mastic in Dedham
Most frames have an outside joint and an inside one. The external joint is the weather seal; inside, the joint between frame and plaster stops draughts and tidies the reveal. Either or both can be done. We’re often asked to deal with water coming in at the bottom corners of a door and old mastic that has gone black or come away, on patio & French doors, composite doors and timber windows & doors.
Mastic can only go onto a dry, clean joint, so window work in Dedham is booked around the forecast. Let us know about access to all the frames, upstairs ones included.
Big or small, you get the same 12-month guarantee.
- Place
- Dedham (CO7)
- Wider area
- Essex
- Guarantee
- 12 months on all our work
- Price
- A clear quote up front
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
What happens if it’s left?
If you’re painting or rendering, reseal at the same time. Fresh joints finish the job neatly. Older cottages and farmhouses around Dedham can have timber floors and frames, where water from a failed joint can cause rot if it’s left.
What you pay reflects the work, not a rough estimate. That is why we ask about the job first and give you a clear price before any work starts.
Why choose Mr Mastic in Dedham
- Colour picked to suit the job
- More than 20 years in sealant work
- Rated 4.9 stars on Google
- White, clear, grey or coloured to suit, where the product allows
What we cannot put right
We’d rather tell you now than do work that won’t last, so here’s what sealant cannot put right:
- A sash or casement that will not close properly
- Misting between the panes of a double-glazed unit (that needs a new unit)
- Draughts through the window seals rather than the frame
If in doubt, call 0345 464 0079 or drop us an email and we’ll say what we think.
Joints and surfaces we work on
- Aluminium frames
- Composite doors
- Window sills
- Timber windows & doors
- uPVC windows
- Patio & French doors
Also in Dedham
Dedham: your questions answered
Do you cover Dedham for window mastic?
Yes, Dedham is within the area we cover. Our work covers London and the South East. Just phone 0345 464 0079 or send us an email with a few details of the job.
Do you work for landlords with property near Manningtree 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 do you need from me for a quote?
A short description and the location. We will ask anything else we need to know.
Will there be a smell?
That depends on the sealant. Some products have a noticeable smell, others very little, and any smell fades as they cure.
Can I do it myself?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Can you do the inside joint as well?
Yes. The outside joint keeps the weather out, and the inside joint stops draughts and finishes the reveal. We can do either or both.
What do you put in the joint?
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.
Can you do several jobs on one visit?
Yes, we can. Several rooms, windows or areas can go on one quote.
Looking after it afterwards
How long the joints last depends on use and care. Here’s what we suggest:
- Repaint timber before it’s bare
- Use gentle cleaners on frames and sealant
- Wipe condensation off the frames
- Keep paint off silicone joints
Wipe the frames with soapy water when you clean the windows, and avoid solvent cleaners on the sealant.
Signs to watch for: cracks in the mastic, gaps you can see light through, damp on the reveal or mould around the inside of the frame. Any of these is worth a call.
When to call us in Dedham
Sills take more water than any other part of a window, so the sill ends and the joint below the frame are common leak points. Failed sealant there lets rain into the wall or behind the frame.
Common reasons people contact us include:
- Whistling draughts around closed windows
- Cracked internal joints between frame and plaster
- Sealant in the wrong colour for the frame
- Damp patches on the reveal after heavy rain
For landlords with property near Manningtree station, cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets.
What to look for in a quote
- How hidden problems are handled
- How the colour is chosen
- Is the old sealant removed completely?
- When the joint can take water or movement
Windows and doors in Dedham
The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. Historic houses like Castle House (about 0.5 miles south-east) are a reminder that the area around Dedham has older buildings as well as new. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic.
For an older house near a landmark such as Parish Church of St Mary, the joint between an old wall and a newer frame is normally the first place rain gets in. If you look after a building such as Dedham Church of England Voluntary Controlled Primary School, the mastic around its windows and doors needs looking after like any other building’s.
Dedham is about 6 miles north-east of Colchester, in Essex. Whether you’re in the middle of Dedham or further out, window mastic is available for homes and businesses alike, from flats and houses to offices and hotels. Across Essex, we cover 644 places, and Dedham is one of them. There’s also a page for Chelmsford, roughly 26 miles from Dedham.
Every address in CO7 is within our area for window mastic. You’ll find streets such as High Street, School Lane and The Drift, and we cover them all. Nearby, we also carry out window mastic in Lamb Corner (1 mile south-west), Dedham Heath (1 mile south), Stratford St Mary (1 mile north-west), Ardleigh Heath (2 miles south) and Higham (2 miles north-west). We also work in nearby towns such as Colchester (6 miles south-west), Clacton-on-Sea (13 miles south-east), Harwich (12 miles east), Camulodunum (7 miles south-west), Halstead (15 miles west) and Greenstead (5 miles south-west).
What’s near Dedham
Locally, jobs take us to homes and businesses close to The Sun Inn and East Bergholt High School. The nearest railway station is Manningtree station, roughly 2.4 miles east. A little further out are Severalls Hospital (4.9 miles south-west) and Little Wenham Castle (4.1 miles north-east). For a walk, there’s Cattawade Marshes.
Can I do it myself?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and does not move well, and the joint depth matters as much as the finish.
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
What happens on the day
You do not need to clear the whole room or building, only the area right around the joints. We protect the rest, and the work takes a few hours for a handful of frames, longer for a whole house in most cases. Somewhere as small as Dedham, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- Each frame is looked over and we agree which ones need resealing.
- The old mastic is cut out and scraped back to clean surfaces.
- Deep gaps get closed-cell backing rod to set the depth.
- A flexible exterior sealant is applied in a colour to suit the frame.
- Every joint is tooled smooth and checked before we leave.
Getting ready for the visit
- Tell us about access, such as stairs, a lift or high-level joints
- Mention any leaks or damp you’ve noticed
- Plan for the work area to be out of bounds to pets and children
Get a quote
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is. Whenever you are ready, ring 0345 464 0079 or email us.