Kent · England
Harbledown Window Mastic
Window mastic for Harbledown, by sealant specialists with 20+ years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Rushed sealant from a window installation
- White mastic on grey or black frames
- Black, perished sealant on frames
Window mastic for homes and businesses in Harbledown
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. We seal one or both, depending on what’s needed. We work on window sills, patio & French doors and uPVC windows, and common reasons people get in touch are gaps between the frame and the inside reveal and cracked or shrunken mastic around the frame.
Homes in small places like Harbledown often stand in the open, with little to shelter their windows from wind and rain. That exposure dries out and cracks the mastic around frames and sills faster.
Our work is backed for twelve months, in Harbledown and everywhere else we cover.
- Place
- Harbledown (CT2)
- Region
- Kent
- Guarantee
- A year, on every job
- Quote
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Looking after it afterwards
How long the joints last depends on use and care. Here’s what we suggest:
- Don’t paint over the silicone
- Do not aim a pressure washer at the joints
- Keep paint and stain on wooden frames in good order
- Look round the frames every year or so
Clean the frames with mild soapy water, and avoid solvent cleaners on the sealant.
Look out for the warning signs: split or missing mastic, gaps, damp patches inside or black mould on the reveal. If you notice one, it’s time to get the joint looked at.
Also near Harbledown
More services for Harbledown
Harbledown homes and the weather
The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
If you let a flat or house near Canterbury West station, cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets. In the older streets around St Michael and All Angels Church, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint.
Harbledown is about 1 mile west of Canterbury, in Kent. Homes, rented property, offices and hotels in Harbledown is covered for window mastic, old or new, large or small. Every job comes with our one-year guarantee. Our area takes in 922 places across Kent, large and small. For nearby work, see our Chelmsford page, about 40 miles away.
Postcode districts we cover here for window mastic: CT2. That includes homes and businesses on Lanfranc Gardens, Mill Lane and Church Hill and the roads around them. We also cover the places around Harbledown: Rough Common (1 mile north-west), Wincheap (1 mile south-east), Thanington (1 mile south), Upper Harbledown (1 mile west) and Canterbury (1 mile east). Further out, we also cover Ashford (13 miles south-west), Dover (14 miles south-east), Sittingbourne (15 miles west), Folkestone (14 miles south), Whitstable (5 miles north) and Deal (15 miles east).
Near you in Harbledown
We work in homes and buildings around Whitehall Meadows, St Edmund's School and The Monument Inn. Nearby too are St Thomas of Canterbury Church (1.2 miles east) and The Canterbury Academy (less than half a mile south-east). The closest station to Harbledown is Canterbury West station, about 0.8 miles east. A little further out are Eastbridge Hospital of St Thomas the Martyr (0.9 miles east) and Sidney Cooper Museum (0.9 miles east). Not far away are Blean Woods RSPB Reserve.
How the visit works
You don’t need to clear the whole room or building before we come, only the area right around the joints. Everything nearby is protected, and the work takes a few hours for a handful of frames, longer for a whole house for a typical job. Somewhere like Harbledown needs a little journey planning: tell us about narrow lanes, gates, long drives and where we can park. Everything for the job comes with us, so a second trip is avoided where possible.
- First, we go round the frames with you and agree the list.
- We remove the old mastic and clean the frame edge and wall.
- Where the gap is deep, backing rod goes in first.
- The new sealant goes on in white, brown, anthracite grey, black or clear to suit.
- Every joint is tooled smooth and checked before we leave.
Preparing for the visit
- Tell us about any previous sealing or DIY attempts
- Mention any leaks or damp you’ve noticed
- Plan for the work area to be out of bounds to pets and children
Ask for a quote
It all starts with a short chat. Describe the problem, the location and the size of the job, and we’ll explain how we’d tackle it. When it suits you, ring 0345 464 0079 or send us an email.
Advice
Harbledown: your questions answered
Do you cover Harbledown for window mastic?
Yes, Harbledown is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or email us and let us know what needs doing.
Will you come out to Harbledown?
Yes. Harbledown is within the area we cover, which takes in towns, villages and rural addresses. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
Do you work for hotels and businesses?
Yes. Commercial and hotel work is a large part of what we do, as well as homes. Working times can be discussed when we quote.
Can you seal the gap between the frame and the plaster indoors?
Yes, we do both. Indoors, we seal between the frame and the plaster or reveal.
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 landlords and businesses book you?
Yes. As well as householders, we work for landlords, agents, businesses and hotels in Harbledown.
How long will my window job take?
A few frames take a few hours. You’ll get a timescale with the quote.
When is the sealant fully cured?
It depends on the product and the conditions. We tell you how long to leave it before we go.
When it isn’t the sealant
We’d rather tell you now than do work that won’t last, so these are the limits:
- Misting between the panes of a double-glazed unit (that needs a new unit)
- A door that needs adjusting, rehanging or new seals
- Broken hinges, locks or handles
If you’re not sure, just phone 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
- Patio & French doors
- Aluminium frames
- Timber windows & doors
- uPVC windows
- Composite doors
- Window sills
What happens if it’s left?
A quick bead over the top of old mastic looks like an easy fix, but new sealant cannot bond to old, crumbling mastic. It soon lifts and the leak carries on behind it. The old mastic has to come out. In a small place like Harbledown, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
Every job is a little different, so each one gets its own quote. Size, access and the product the joint needs all make a difference.
Why book with us
- 180+ five-star Google reviews
- We agree the colour with you first
- Colour picked to suit the job
- Any old sealant cut out fully, not covered over
Take a look at what affects the cost or what customers say.
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, and the work is guaranteed for a year.
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
Different surfaces, different methods
Timber windows & doors
Wood swells when it’s wet and shrinks when it dries, so the joint must stay flexible. The paint or stain needs to be sound where the sealant meets it.
Patio & French doors
Water at the foot of a door frame is not always the mastic: worn seals, blocked drainage slots or a poor threshold detail can be the cause. We look for the cause first.
Do you need window mastic in Harbledown?
Every frame moves through the day. Sun on a frame makes it expand, and it contracts again overnight, while the masonry beside it stays put. If the sealant can’t stretch, it splits.
Keep an eye out for any of the following:
- Untidy mastic left by window fitters
- Damp patches on the reveal after heavy rain
- Mastic that has split away from the wall
- Gaps where the sill meets the wall
Managing a site like The Canterbury Primary School? Then larger buildings have plenty of frames, and the mastic around each one ages.
Before you book anyone
- Whether they’re fully insured
- What the quote includes, VAT included or not
- What guarantee comes with the work
- Whether they seal over old material or remove it