Greater London · England
Sand mastic for sash & case windows in Adelphi, Greater London
Problem with your window and door surrounds in Adelphi? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Gaps between timber frames and stone or brick
- Cement or filler used on old window joints that has cracked
- Mastic dropping out of the joint
How we quote for sand mastic
Some jobs are bigger than they look, and some smaller. What affects the quote:
- Working hours on commercial sites
- Whether old sealant or filler has to be cut out
- The number of rooms or windows
- The number and length of the joints
What it costs depends on the size of the job, how much old material has to come out and how easy the joints are to reach. You’ll have a clear quote before any work starts, so you know where you stand.
What to tell us for a quote
A few details help us give you an accurate quote. When you ask for a quote, tell us:
- Whether it’s a home or a business
- Roughly how big the job is
- A few pictures by email, if you can
- If someone has resealed it before
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is. Whenever you are ready, phone 0345 464 0079 or email us.
Sand mastic for homes and businesses in Adelphi
Across Adelphi, we renew sand mastic around sash and case windows. Every joint is cleaned out and filled by hand for a neat, traditional finish. Common call-outs are for modern sealant on a period surround and mastic worn away on windows facing the weather, across period & listed homes, tenement windows and stone surrounds.
Much of London’s older housing was built with timber sash windows, some still in place and some long since replaced. Whatever is in the opening now, the joint between frame and wall is what keeps the weather out, in Adelphi as anywhere.
The work is guaranteed for twelve months. If something isn’t right with it in that time, tell us and we will put it right.
- Location
- Adelphi (W1D, W1F, WC2H)
- Region
- Greater London
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Nearby places to Adelphi
What else we do in Adelphi
How it works
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 anything from a few hours to a full day, depending on how many windows. In Adelphi, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- Each surround is checked first.
- The joint is raked out and cleaned.
- We fill deep gaps so the new mastic is not too thick.
- New sand mastic is applied and shaped by hand.
- The finish is dressed neatly.
Before we arrive
- Plan for the work area to be out of bounds to pets and children
- Tell us about any water getting in
- Mention any parking rules near the property
Getting a quote
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 pictures if that’s easy.
Read more
Looking after it afterwards
So the new joints stay in good condition:
- Find out about consent before window work on a listed home
- Avoid patching sand mastic with silicone
- Keep sills and gutters clear so water drains away
- Ask a joiner to look at soft timber first
Make sure water drains away from the window surround. Water sitting against the mastic shortens its life.
Fine cracks show the mastic is starting to fail. Renewing it then is simpler than waiting until it falls out.
Common questions in Adelphi
Can you help a landlord with a rental near London Charing Cross station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. Just call 0345 464 0079 or send us an email with the address and what needs doing, and we’ll give you a clear quote.
Is parking an issue for sand mastic in Adelphi?
Parking in Adelphi, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly.
Will there be a smell?
There can be a smell while the sealant cures. Opening a window helps.
How long does sand mastic take to go off?
It skins over fairly quickly but takes longer to harden fully. We’ll explain what to expect before we leave.
Does someone need to be in?
If the work is inside, we need someone to let us in. After that, you can carry on with your day.
Is it messy?
Not at all. We work neatly, protect the area around the joints and tidy up afterwards.
Can I paint the new mastic?
It’s traditionally left unpainted, as guidance on traditional windows advises. Ask us before decorating.
Which products do you use?
Each joint gets the product that suits it. Movement, water and weather all affect the choice, and we’ll tell you what we are using.
Signs you need sand mastic in Adelphi
Most of it is simply age. Even well-laid mastic needs renewing in time and how long it lasts depends on the weather it faces.
People usually contact us after spotting something like this:
- Patchy fillers round a sash window
- Cracked mastic round a front door frame
- Draughts and rain around sash boxes
- Gaps between timber frames and stone or brick
Managing a site like St Clement Danes CofE Primary School? Then larger buildings have plenty of frames, and the mastic around each one ages.
Before you book anyone
- What the quote includes, VAT included or not
- Is the old sealant removed completely?
- How long to leave it before use
- Who does the work, and how experienced they are
Different surfaces, different methods
Tenement and terrace windows
Rows of sash windows on tenements and terraces often need renewing together. We can do one window or several.
Brick reveals
Loose mastic comes out and deep gaps are packed before the new mastic goes in.
Frames and glazing around Adelphi
The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. In London conversions and blocks, the lease decides who is responsible for the frames, so it’s worth checking before booking.
Adelphi is in London, so parking needs planning: let us know about parking bays, permits or a driveway. Letting a property close to London Charing Cross station? Then any sash windows need sound mastic to keep draughts and rain out.
Adelphi is about 1 mile south-east of Marylebone, in Greater London. Our applicators cover sand mastic for homeowners, landlords and businesses in Adelphi and nearby. Our Greater London coverage runs to 764 places, Adelphi among them.
Every address in W1D, W1F and WC2H is within our area for sand mastic, from the main roads to the quietest streets. Streets in the area include York Road, Drury Lane and Maiden Lane, all of which we cover. With the A301 and A400 close by, Adelphi is simple for us to get to. Neighbouring places we cover for sand mastic include Covent Garden (1 mile north), Charing Cross (1 mile south-west), Aldwych (1 mile north-east), Seven Dials (1 mile north-west) and West End (1 mile north-west). We also work in nearby towns such as Kensington (3 miles west), Walthamstow (7 miles north-east), Hampstead (4 miles north-west), Ruislip (13 miles west), Stockwell (3 miles south) and Orpington (13 miles south-east).
Landmarks near Adelphi
In Adelphi, that means homes and buildings near The BFI Reuben Library, St Andrew's and St John's Church of England Primary School and London Nautical School and the streets around them. Also close by are Victoria Embankment Gardens (under half a mile south) and The Theodore Bullfrog pub (less than half a mile south-west). Adelphi has its own railway station: London Charing Cross station. A little further out are London Museum and Institute of Natural History (within half a mile north-east) and Montfichet's Tower (1 mile east). Green spaces nearby include St. James's Park Lake and Barnsbury Wood.
DIY versus a professional finish
Some sealant jobs are within reach of a careful DIYer, 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 a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions, and the work is guaranteed for a year.
Leave it or put it right?
An open joint round the frame lets weather in. Left, water can reach the timber and the wall so renewing it early protects the window. Converted houses in London often have a bathroom above someone else’s living room, and a slow leak from a failed seal can end up in the flat below. Putting it right early is much less trouble for homes in Adelphi.
No two jobs are quite the same, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all make a difference, and we’ll explain the quote if you ask.
Why us?
- Quality sealants from Arbo and Everbuild
- Fully insured
- Approved under the ARBOMaster scheme
- 4.9 on Google from 180+ five-star reviews
Read how sealant jobs are priced and our reviews.