Greater London · England
Millwall Sand Mastic
Traditional burnt sand mastic around sash and case windows and doors in stone and brick in Millwall, with a 12-month guarantee on every job. Call for a quick quote.
- Draughty sash windows at the surround
- Gaps where the frame meets the masonry
- Tired mastic found when preparing windows for paint
Sand mastic in Millwall
Sand mastic has long been used to fill the joint between timber frames and masonry. It’s made from sand and a linseed-oil-based binder, applied by hand. On older homes, it suits the building far better than silicone. We work on timber door frames, tenement windows and brick reveals, and common reasons people get in touch are weathered mastic on the most exposed windows and a silicone bead on a sash window that spoils the look.
London has a lot of flats and conversions, where windows are often on upper floors. In a converted house or block, the lease normally says who is responsible for the windows, so it’s worth checking before booking.
Every job is covered by our 12-month guarantee.
- Where
- Millwall (E14, SE8, SE10)
- Region
- Greater London
- Guarantee
- 12 months on all our work
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
How to look after the new joints
To keep the joints looking good and working properly:
- Ask the planning authority about consent for listed or conservation-area homes
- Check the mastic when you check the paintwork
- Take care around the mastic when scraping paint
- Sort the mastic before the decorators arrive
Check the mastic when you check the paintwork. Small cracks are easier to deal with early.
Sound mastic protects the frame. Failed mastic lets water reach the timber and timber that stays wet can rot.
Windows and doors in Millwall
Historic houses like Queen's House (about 0.9 miles south-east) are a reminder that the area around Millwall has older buildings as well as new. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window. London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Millwall is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. Letting a property close to Deptford station? Then older sash windows in a rental need their mastic kept sound to keep the weather out.
Millwall is about 1 mile north-west of Greenwich, in Greater London. From the centre of Millwall to the outskirts, sand mastic is available for homes and businesses alike. Across Greater London, we cover 764 places, Millwall among them.
Every address in E14, SE8 and SE10 is within our area for sand mastic. If you need sand mastic at a property on Creek Road, Wynan Road and Undine Road or anywhere close by, we can help. We also cover the places around Millwall: North Greenwich (1 mile east), Isle of Dogs (1 mile east), Deptford (1 mile south), Cubitt Town (1 mile north-east) and Greenwich (1 mile south-east). Within a short drive, we also cover London (3 miles west), City of Westminster (6 miles west), Marylebone (6 miles west), Kensington (8 miles west), St Pancras (5 miles north-west) and Shoreditch (4 miles north-west).
What’s near Millwall
Locally, jobs take us to homes and businesses close to Canary Wharf College 3, St. Paul's and Mudchute Park and Farm and the streets around them. Other local landmarks include The Ferry House Public House (less than half a mile south-east) and Laban Centre (0.6 miles south). For rail, the closest station is Deptford station, about 0.8 miles south-west. A little further out are Surrey Quays Shopping Centre (1.2 miles west) and Old Royal Naval College (0.7 miles south-east). Not far away are Tower Hill and Sue Godfrey Nature Park.
The process
On the day, there’s very little for you to do. Show us the job and we’ll take it from there. The work itself takes a few hours for a single window, longer for several from start to finish. In Millwall, as in most of London, parking needs a little planning. It helps if you can point us to a visitor permit or a bay close to the door.
- First, we look at the surrounds with you and agree what needs doing.
- The loose and crumbling mastic is raked out and the joint cleaned.
- Large voids are packed out first, so the mastic is not too thick.
- The mastic is mixed, pressed into the joint by hand and shaped.
- The mastic is finished to sit tidily against the stone or brick.
Preparing for the visit
- Plan for the work area to be out of bounds to pets and children
- Move anything stored near the joints
- On commercial sites, let us know about site rules
How to get a quote
For a quote, ring 0345 464 0079 or email us with the location and a short description of the problem. You’ll have a clear quote before any work starts.
Related advice
Nearby places to Millwall
Other services in Millwall
Quotes for sand mastic in Millwall
The price is agreed before any work begins. It’s based on:
- Which sealant suits the joint
- How easy the joints are to reach
- How much old sealant there is and how hard it is to remove
- The amount of work
The cost depends on the amount of work, how hard the old material is to remove and access to the work. We give a clear quote before any work starts.
What we need to know
A few details help us give you an accurate quote. When you get in contact, it helps to mention:
- Any access issues, like height or stairs
- The rough size of the job
- If someone has resealed it before
- The address or postcode of the job
Call for a quick quote, or send an email if you’d rather. Tell us about the joints that need doing and we will talk you through the work and give you a clear price.
Do you need sand mastic in Millwall?
Water gets into small cracks in the mastic and loosens it further. Windows facing the weather tend to go first.
The problems people normally mention when they call include:
- Mastic worn away on windows facing the weather
- Crumbling sand mastic round a window
- Wind and rain getting in round a sash window
- Cracked mastic round a front door frame
In the older streets around Church of St Nicholas, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Before booking anyone
- Which sealant they’ll use, and why
- Is VAT in the price?
- When the joint can take water or movement
- Is the old sealant removed completely?
Common questions in Millwall
Is Millwall in your area for sand mastic?
Yes. Our work covers London and the South East, and Millwall is part of that. Just ring 0345 464 0079 or email us with a few details of the job.
I let a flat near Deptford station. Can you help?
Yes. We work for landlords and letting agents as well as homeowners. You can ring 0345 464 0079 or email us with the details for a clear quote.
Can you do several jobs on one visit?
Yes. Just list everything you need and we’ll quote it together.
What is sand mastic?
It’s a mix of sand and a linseed-oil-based binder. It’s applied by hand and finished to sit neatly against the masonry.
Do you take out the old sealant first?
Yes, every time. New sealant will not bond properly to old, so any old material comes out before anything new goes in.
Where is Mr Mastic based?
We’re a Crawley-based firm. Our area covers South East England, London and Scotland.
What do you need from me for a quote?
Tell us what needs doing and where, with photos by email if possible. We will ask anything else we need to know.
Do you work for hotels and businesses?
Yes. Larger jobs can be planned room by room or area by area to suit the site.
What the job involves on each surface
Stone surrounds
Stone surrounds suit sand mastic well. The finish blends with the masonry.
Brick reveals
Gaps between frame and brick let in rain and draughts. New mastic seals the gap.
Why deal with it now?
New mastic over crumbling mastic won’t hold. Raking out and preparing the joint gives it a sound base so the new work lasts. In older London homes, water behind a failed joint soaks into brick and timber without much sign, and by the time it shows on a wall or ceiling in Millwall, the repair is bigger than the sealant job would have been.
A failed joint rarely gets cheaper to fix by waiting, as water and mould keep getting in. If you’re not sure whether it needs doing, ring 0345 464 0079 or email us and we’ll give you an honest view and a quote.
Why book with us
- 20+ years of sealant experience
- 4.9 on Google from 180+ five-star reviews
- Every job guaranteed for a year
- Neat joints and a tidy finish
Take a look at our cost guide and what customers say.
When something else is needed
Honest advice matters more to us than a booking, so here’s what new sealant won’t do:
- Broken panes
- Crumbling stone or brickwork round the window
- Sash cords, weights and draught-proofing of the sashes
Not sure which it is? You can phone 0345 464 0079 or drop us an email and we will tell you honestly before booking.
Surfaces we seal
- Tenement windows
- Brick reveals
- Sash and case windows
- Period & listed homes
- Stone surrounds
- Timber door frames