Greater London · England
Osidge Sand Mastic
Problem with your window and door surrounds in Osidge? We cut out the old, prepare the joints and apply the right sealant, with a one-year guarantee.
- Gaps round a timber door in stone or brick
- Crumbling sand mastic round a window
- Cement or filler used on old window joints that has cracked
Do you need sand mastic in Osidge?
Age is the main cause. Sand mastic is a maintenance item like any pointing, depending on exposure and upkeep.
Keep an eye out for any of the following:
- Silicone on a period window that looks wrong
- Mastic round period door frames that has failed
- Wind and rain getting in round a sash window
- Crumbling sand mastic round a window
Homes close to St Andrew's Church include some older properties, and the joint between an old wall and a newer frame is generally the first place rain gets in.
What to look for in a quote
- How hidden problems are handled
- Who turns up on the day
- How the joint is cleaned and prepared
- Whether all the old sealant comes out first
About our sand mastic in Osidge
On many period windows, sand mastic looks right and suits the building. On modern frames we’d normally use a flexible sealant, and we will talk through which suits your home. If you have mastic that needs renewing before redecorating and silicone on a period window that looks wrong, we can put it right, on sash and case windows, stone surrounds and tenement windows alike.
London has a lot of flats and conversions, where windows are often on upper floors. In a converted house or block, the lease usually says who is responsible for the windows, so it’s worth checking before booking, and access in Osidge is something to talk through when you book.
A 12-month guarantee comes as standard, so you’re not left on your own once the job is done.
- Where
- Osidge (N14, EN4, N11)
- Region
- Greater London
- Cover
- A year, on every job
- Quotes
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
What the job involves on each surface
Stone surrounds
Old stone surrounds are often uneven, so the gap isn’t the same all the way round. Sand mastic is shaped by hand to suit.
Brick reveals
Brick reveals round timber windows are often pointed with sand mastic. It gives a traditional finish.
Also in Osidge
Should I try it myself first?
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Honest limits
We will not take on work that will not last, so here’s what sealant cannot put right:
- Masonry that needs repairing
- Whether work needs listed building consent
- Timber that has rotted
If in doubt, phone 0345 464 0079 or send us an email and we’ll say what we think.
Joints and surfaces we work on
- Brick reveals
- Sash and case windows
- Stone surrounds
- Tenement windows
- Period & listed homes
- Timber door frames
The process
When we arrive, we look over the joints with you first, so there are no surprises. We protect the surfaces around the joints before we start. The work usually takes a few hours per window, depending on the condition of the joints. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Osidge. It helps if you can point us to a visitor permit or a bay close to the door.
- We check each window surround and the condition of the joint.
- We rake out the old mastic and clean the joint.
- Large voids are packed out.
- New sand mastic is applied and shaped by hand.
- We finish the mastic to a tidy line.
Getting ready for the visit
- Mention any tricky access
- Keep children and pets away from the work area
- On commercial sites, let us know about site rules
Getting a quote
For a quote, call 0345 464 0079 or send us an email with the location and a short description of the problem. You’ll have a clear quote before any work starts.
Advice
What affects the cost of 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 amount of work
- Access and height
Instead of a standard rate, we look at what your job involves: how many joints, what’s in them now and how we reach them. You’ll know the price before we begin.
Asking for a quote
To help us quote quickly, let us know:
- Whether it’s a home or a business
- How many joints, rooms or windows are involved
- Where the job is, and your postcode
- Any access issues, like height or stairs
Call for a quick quote, or send an email if you’d rather. Describe what needs sealing and we’ll talk you through the work before giving you a price.
Osidge: your questions answered
Is parking a problem for a job in Osidge?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. That way the visit can be planned around it.
Can you do sand mastic in Osidge?
Yes, Osidge is within the area we cover. We work across London and the South East. You can call 0345 464 0079 or drop us an email and tell us what needs doing.
What should I tell you?
The location, the problem and the rough size of the job. If you can, email a few pictures.
Which is right for my windows, sand mastic or modern sealant?
We will talk it through with you. Period homes often look best with sand mastic and newer frames suit modern sealant.
Is it OK to seal over old sealant?
No. Fresh sealant does not stick to old sealant, and anything trapped underneath, including mould and water, stays there. We remove it all first.
What do you put in the joint?
Quality sealants from brands including Arbo and Everbuild, picked for each joint. We explain the product when we quote.
Can landlords and businesses book you?
Yes. Domestic, commercial and hotel work are all part of what we do.
Does someone need to be in?
We need access to the joints, so we’ll agree that with you when we book. Indoors, that generally means someone at home.
Landlord and commercial work in Osidge
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
Failed sealant is one of the commonest items on a check-out report, and it’s quick to put right between tenancies. We can quote for more than one property at once.
What sand mastic looks like in Osidge
Historic houses like Bruce Castle (about 3.8 miles south-east) are a reminder that the area around Osidge has older buildings as well as new. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window. 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 Oakleigh Park station, older sash windows in a rental need their mastic kept sound to keep the weather out. Schools such as Monkfrith Primary School are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages.
Osidge is about 2 miles south-east of Barnet, in Greater London. Osidge gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a one-year guarantee. Our Greater London coverage runs to 764 places, and Osidge is one of them. For nearby work, see our London page, about 10 miles away.
Every address in N14, EN4 and N11 is covered for sand mastic. You will find streets such as Dene Road, Farm Lane and Byre Road. Osidge is on the A111, which makes it straightforward to reach. Other places close to Osidge include Southgate (1 mile south-east), East Barnet (1 mile west), Brunswick Park (1 mile south-west), Oakwood (1 mile north-east) and Whetstone (1 mile south-west). Larger places within reach include London (10 miles south), City of Westminster (8 miles south), Marylebone (8 miles south), Kensington (10 miles south), St Pancras (8 miles south) and Shoreditch (8 miles south).
What’s near Osidge
Locally, jobs take us to homes and businesses close to Oak Hill Park, The Osidge Arms and Salcombe School, among other places. For rail, the closest station is Oakleigh Park station, about 1 mile west. Well-known places in the area include Broomfield House Museum (1.6 miles south-east) and Grand Arcade (2.1 miles south-west). Not far away are Darland's Lake and Barfield Allotments Nature Park.