Greater London · England
Window & door mastic in Crook Log, Greater London
We cover Crook Log for mastic around window and door frames, sills and patio doors. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Cracked sealant at the sill ends
- Mastic that is falling out in pieces
- White mastic on grey or black frames
Window mastic for homes and businesses in Crook Log
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. If you’re dealing with leaking joints at the ends of sills and cold air getting in at the frame edge, we can help, on window sills, timber windows & doors and uPVC windows alike.
From mansion-block windows to modern glazing in new flats, London has every kind of frame. Over the years, the sealant around them shrinks, cracks and pulls away, which is when draughts and damp patches appear in homes in Crook Log.
Each job carries a 12-month guarantee, large or small.
- Location
- Crook Log (DA7, DA6, DA16)
- Wider area
- Greater London
- Guarantee
- A year, on every job
- Quote
- A clear price before we start
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Crook Log: your questions answered
Is parking a problem for a job in Crook Log?
Parking in Crook Log, as in most of London, takes a little planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
Do you cover Crook Log for window mastic?
Yes. Our work covers London and the South East, and Crook Log is part of that. You can phone 0345 464 0079 or drop us an email and let us know what needs doing.
Can new sealant go over the old?
No. Fresh sealant does not stick to old sealant, and anything trapped underneath, including mould and water, stays there. It all has to come out first.
Can I add another job to the visit?
Yes. More than one area can go on one quote.
Will the old sealant be removed?
Always. Sealing over old sealant is the main reason resealing fails early, and it’s something we never do.
Does someone need to be in?
Access is agreed with you when the job is booked. Indoors, that normally means someone at home.
Does the work come with a guarantee?
Yes. Our one-year guarantee covers every job, inside or out.
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 do one or both.
Common problems we fix in Crook Log
On timber frames, paint and putty build up around the joint. Mastic painted over many times cracks with the paint, and timber moves with moisture as well as temperature.
If you can see any of these, it’s time to have the joints looked at:
- Cracked internal joints between frame and plaster
- Sealant in the wrong colour for the frame
- Damp patches on the reveal after heavy rain
- Gaps where the sill meets the wall
If you live in an older home near Trinity Baptist Church, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Comparing quotes
- Whether you can choose the colour
- How long the guarantee is
- How hidden problems are handled
- Whether all the old sealant comes out first
Leave it or put it right?
A quick bead over the top of old mastic looks like an easy fix, but new sealant can’t bond to old, crumbling mastic. It soon lifts and the leak carries on behind it. Proper resealing starts with removing the old joint. In London conversions, one flat’s bathroom is often above another flat’s ceiling, so a small leak from tired sealant can mean a neighbour’s ceiling and a lot of disruption. Dealing with it early is far simpler for homes in Crook Log.
A few things move the cost up or down: how much old sealant there is and how stubborn it is, any mould to treat, and whether the work is at height. Your quote takes all of that into account.
Why Crook Log clients choose us
- 12-month guarantee on every job
- 20+ years of sealant experience
- Any old sealant cut out fully, not covered over
- White, clear, grey or another colour, product permitting
Take a look at what affects the cost and customer reviews.
Honest limits
In fairness, some problems need a different trade:
- A failed sealed unit that has misted up
- A frame that has rotted at the joint
- Faulty window hardware
If in doubt, ring 0345 464 0079 or email us and we will say what we think before you book.
Where we work in Crook Log
- Patio & French doors
- Window sills
- Composite doors
- Timber windows & doors
- Aluminium frames
- uPVC windows
Landlord and commercial work in Crook Log
Businesses can book us for washrooms, kitchens, offices and more. For commercial premises, we can talk through working times when we quote.
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance that we can handle for you.
Nearby places to Crook Log
More services for Crook Log
Aftercare tips
After the cure time, these simple habits help:
- Keep jet washers away from the mastic
- Keep paint and stain on wooden frames in good order
- Clean frames with a soft cloth and soapy water
- Walk round the house once a year and look at the joints
A yearly look round the frames is enough. Cracks and lifting edges are easy to spot early.
A failed joint lets water into the wall a little at a time. You might not see it until plaster blows or a damp patch appears inside. Early resealing stops it reaching that point.
What happens on the day
Good joint work is mostly preparation, so that’s where we spend the time. Every joint is cleaned and dried before new material goes in. All told, the work takes anything from an hour or two to a full day, depending on how many frames there are. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- We check each frame and agree which ones need doing.
- The old mastic is cut out and the surfaces cleaned back.
- Where gaps are deep, backing rod goes in first.
- We apply a weatherproof sealant to match the frame and tool it neatly.
- We clear up and check every joint is fully closed.
How to prepare
- Let us know if you’ve seen damp or leaks
- Let us know about stairs, lifts or work at height
- Tell us about any previous sealing or DIY attempts
Getting a quote
We don’t publish a price list, because every job is different. Instead, we send you a clear quote for your job. To arrange one, call 0345 464 0079 or email us.
Related advice
Window mastic in Crook Log: local notes
In a converted house or block, who looks after the windows depends on the lease, so it’s worth checking before booking. 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.
Crook Log is in London, so parking needs planning: let us know about parking bays, permits or a driveway. If you look after a building such as Crook Log Primary School, its window and door frames need their mastic kept sound, just like a home’s.
Crook Log is about 3 miles south-east of Plumstead, in Greater London. Across the DA7 area, our applicators can take on window mastic. Our Greater London coverage runs to 764 places, Crook Log among them. Our London page covers work nearby (10 miles or so).
Jobs for window mastic in DA7, DA6 and DA16 works the same way as everywhere else we cover. Streets in the area include Bean Road, Lion Road and Alers Road, all of which we cover. We also cover Upton (1 mile east), Bexleyheath (1 mile east), Welling (1 mile west), Blendon (1 mile south) and Bexley (1 mile south). Within a short drive, we also cover London (10 miles west), City of Westminster (13 miles west), Marylebone (12 miles west), Kensington (14 miles west), St Pancras (11 miles north-west) and Shoreditch (10 miles north-west).
Near you in Crook Log
Locally, jobs take us to homes and businesses close to Danson Park, St Columba's Catholic Boys' School and The Crook Log Public House and the streets around them. Crook Log has its own railway station: Bexleyheath station. Nearby you will also find Bexley Museum (1.7 miles south-east) and Broadway Shopping Centre (0.9 miles east). The countryside around Crook Log includes Summer Hill and Wansunt Pit.
What affects the quote in Crook Log
We quote each job individually. These are the things that affect it:
- Access and height
- The old material and how stubborn it is
- The type of sealant required
- How many areas need sealing
A failed joint rarely gets cheaper to fix by waiting, as water and mould keep getting in. If you’re unsure, ring 0345 464 0079 or drop us an email for an honest opinion and a quote.
What we need to know
To help us quote quickly, let us know:
- How many joints, rooms or windows are involved
- Whether it has been sealed before
- Whether it’s a home or a business
- How we’d reach the joints
Asking for a quote is easy: let us know the job and the location. A few photos by email make the job easier to understand, and we’ll come back to you with a quote.