Greater London · England
Sand mastic for sash & case windows in Deptford, Greater London
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for Deptford, backed by a one-year guarantee. Call for a quick quote.
- Window mastic to renew ahead of painting
- Draughty sash windows at the surround
- Old cement repairs round a window that have failed
DIY versus a professional 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.
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
About our sand mastic in Deptford
Sand mastic is the traditional way to point the gap between a timber window frame and the stone or brick around it. It’s a mix of sand and a linseed-oil-based binder, applied by hand. On older homes, it suits the building far better than silicone. We work on period & listed homes, timber door frames and brick reveals, and people most often call us about window mastic to renew ahead of painting and gaps round a timber door in stone or brick.
London homes have every kind of window, from timber sashes in period terraces to aluminium and uPVC in newer blocks. The mastic around them dries out and cracks with age, letting in draughts and water.
Our work is backed for twelve months.
- Where
- Deptford (SE8, SE10, SE14)
- Region
- Greater London
- Cover
- A year, on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
Places near Deptford
Also in Deptford
Landlord and commercial work in Deptford
From a single let to a portfolio, the work is the same standard: the old material taken out, careful preparation and a 12-month guarantee.
Mouldy or split sealant often shows up at the end of a tenancy, and it’s easy to sort out between tenants. We can quote for more than one property at once.
Common questions in Deptford
Is Deptford in your area for sand mastic?
Yes, Deptford is within the area we cover. Our work covers London and the South East. Just call 0345 464 0079 or drop us an email with a few details of the job, and we will give you a clear quote.
Can parking be tricky for a visit in Deptford?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
Is sand mastic better than silicone for my windows?
It depends on the window. On many period windows, sand mastic looks right and suits the building and newer frames usually get a flexible sealant.
Is there any odour?
That depends on the sealant. Some smell for a while, some hardly at all, and any smell fades as they cure.
I’m a tenant. Can you help?
Yes. Ask your landlord first, and we can send them the quote if that helps.
Should I try DIY first?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. Most DIY failures come from sealing over old material, wet joints or too much sealant.
Which products do you use?
It depends on the joint: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. Brands we use include Arbo and Everbuild.
Can you match the sealant colour?
Yes. White, clear and grey are common, and other colours are available for many products, and we agree the colour with you before work begins.
Signs you need sand mastic in Deptford
Paint, silicone or cement used over old mastic causes problems. They don’t suit the joint, and they normally need raking out.
Keep an eye out for these signs:
- Gaps where the frame meets the masonry
- Weathered mastic on the most exposed windows
- Patchy fillers round a sash window
- Draughts and rain around sash boxes
Schools such as Tidemill Academy are buildings too, and its window and door frames need their mastic kept sound, just like a home’s.
Before you book anyone
- Who does the work, and how experienced they are
- How long the guarantee is
- How long to leave it before use
- Is VAT in the price?
The process
Good joint work is mostly preparation, and we do not rush it. Every joint is cleaned and dried before new material goes in. In total, it usually takes a few hours per window, depending on the condition of the joints. For a job in Deptford, parking and access are the things to plan: tell us about permits, visitor bays or off-street space, which floor we are working on and whether there’s a lift.
- We check the window surrounds and agree which joints need renewing.
- Old, loose mastic is raked out and the joint cleaned.
- Deep voids are packed so the mastic is the right thickness.
- The mastic is mixed, pressed into the joint by hand and shaped.
- We dress the surface so it sits neatly against the masonry.
Getting ready for the visit
- Mention any leaks or damp you’ve noticed
- Let us know about parking restrictions
- Move anything stored near the joints
Get a quote
Want a quote for sand mastic? Please phone 0345 464 0079 or drop us an email and tell us about the job. You will know what we plan to do, and what it will cost, before any work begins.
Read more
What the job involves on each surface
Brick reveals
Sand mastic is also used where timber frames meet brick. It gives a traditional finish.
Sash and case windows
Sash windows are where we do most sand mastic work. We renew the mastic round each box.
How we quote for sand mastic
For a quick quote, just ask. What matters most is:
- Any mould that needs treating
- How many rooms, windows or areas are involved
- The product the joint needs
- Any working-time requirements on site
We do not show prices on the website, because the cost depends so much on the job itself. For a quick quote, please phone 0345 464 0079 or email us and we’ll talk you through it.
Asking for a quote
The more you tell us, the more accurate the quote. When you get in contact, it helps to mention:
- Roughly how big the job is
- Any previous sealing or DIY work
- A few photos by email, if you can
- What the problem is, such as mould, gaps, leaks or cracking
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is, and email photos if that’s easy.
Deptford homes and the weather
In a converted house or block, who looks after the windows depends on the lease, so it’s worth checking before booking. With historic houses such as Queen's House (about 1 mile east) nearby, there’s older building stock in the area around Deptford 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.
As a London address, Deptford can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. In the older streets around St. Paul's, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Deptford is about 3 miles south-east of Whitechapel, in Greater London. Wherever you are in the SE8 postcode area, we cover sand mastic for homes and businesses. Our Greater London coverage runs to 764 places, and Deptford is one of them.
We cover every part of the SE8, SE10 and SE14 postcode area for sand mastic. You’ll find streets such as Mill Lane, Dixon Road and Clare Road, all of which we cover. You will find Deptford on the A2209, so it’s easy for us to get to with everything needed for sand mastic. We also cover the places around Deptford: New Cross (1 mile south-west), St Johns (1 mile south), Millwall (1 mile north), Isle of Dogs (1 mile north-east) and North Greenwich (1 mile north-east). Larger places within reach include London (3 miles north-west), City of Westminster (6 miles north-west), Marylebone (6 miles north-west), Kensington (8 miles west), St Pancras (5 miles north-west) and Shoreditch (4 miles north-west).
Around Deptford
Around Deptford, our work takes us to homes and buildings near Addey and Stanhope School, Sue Godfrey Nature Park and Deptford Arms and the streets around them. Deptford has its own railway station: Deptford station. Well-known places in the area include Greenwich Castle (1.1 miles east) and Lewisham Shopping Centre (1.3 miles south-east). The countryside around Deptford includes Sue Godfrey Nature Park and Tower Hill.
Why it’s worth doing now in Deptford
Not every draught comes from the sashes themselves. Gaps between the frame and the wall can be just as bad and new mastic seals them. In a flat in Deptford, failed sealant seldom stays inside your own four walls: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
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’ll have a clear quote before any work starts.
What you get with us
- Homes, businesses and hotels
- Anti-fungal sanitary silicone in wet areas
- Full insurance on every job
- 4.9 on Google from 180+ five-star reviews
See our cost guide and customer reviews.