Greater London · England
Sand Mastic in Colindale
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for homes and businesses in Colindale and across Greater London. Fully insured, ARBOMaster approved and guaranteed for a year.
- Mastic that needs renewing before redecorating
- Cracked mastic round a front door frame
- Patchy fillers round a sash window
How we handle sand mastic in Colindale
Across Colindale, we renew sand mastic around sash and case windows. Every joint is cleaned out and filled by hand, finished to suit the masonry. We work on sash and case windows, stone surrounds and tenement windows, and people most often call us about a silicone bead on a sash window that spoils the look and draughty sash windows at the surround.
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.
The work is covered for a year after we finish. If anything isn’t right with it, phone 0345 464 0079 or drop us an email.
- Location
- Colindale (NW9, NW4, HA8)
- Wider area
- Greater London
- Cover
- One year on every job
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Questions from Colindale
Can parking be tricky for a visit in Colindale?
Parking in Colindale, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly.
Is Colindale in your area for sand mastic?
Yes, Colindale is within the area we cover. We work across London and the South East. Just phone 0345 464 0079 or drop us an email with a few details of the job.
Should I use sand mastic or silicone?
We’ll help you decide. Period homes often look best with sand mastic and newer frames suit modern sealant.
What’s sand mastic made of?
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.
Is the work guaranteed?
You get our 12-month guarantee on every job.
Can I add another job to the visit?
Yes. Tell us about everything you’d like done and you’ll get one quote.
Do I have to be there?
We need access to the joints, so we will agree that with you when we book. For inside work, that normally means someone being in.
What do you put in the joint?
Quality sealants from brands including Arbo and Everbuild, chosen to suit the joint. We will tell you what we’re using and why.
What sealant work can’t fix
To be straight with you, some problems need a different trade:
- Cracked or broken glass
- Planning or listed building consent (your local planning authority decides)
- Sashes that need overhauling
If in doubt, ring 0345 464 0079 or email us and we will say what we think before booking.
Joints and surfaces we work on
- Tenement windows
- Sash and case windows
- Timber door frames
- Stone surrounds
- Brick reveals
- Period & listed homes
The process
Before we leave, we go over the finished joints with you and explain the cure time. The visit itself generally takes a few hours per window, depending on the condition of the joints, depending on how much there is to do. In Colindale, 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.
- We check each window surround and the condition of the joint.
- 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.
- We finish the mastic to a tidy line.
Preparing for the visit
- Clear the area around the work
- Tell us about any previous sealing or DIY attempts
- On commercial sites, let us know about site rules
Get a quote
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.
Advice
Frames and glazing around Colindale
In London conversions and blocks, the lease decides who is responsible for the frames, so it’s worth checking before booking. Historic houses like Heath Hall (about 3.5 miles east) are a reminder that the area around Colindale has older buildings as well as new. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic.
For landlords with property near Hendon station, older sash windows in a rental need their mastic kept sound to keep the weather out. Colindale is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Colindale is about 1 mile south-east of Burnt Oak, in Greater London. Jobs in Colindale get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Our Greater London coverage runs to 764 places, and Colindale is one of them. There’s also a page for London, roughly 9 miles from Colindale.
Jobs for sand mastic in NW9, NW4 and HA8 is quoted and booked the same way as anywhere else. If you need sand mastic at a property on Cecil Road, Booth Road and Ajax Avenue or a nearby road, our applicators can take on the job. With the A5150 close by, Colindale is simple for us to get to for sand mastic. We also cover the places around Colindale: West Hendon (1 mile south), The Hyde (1 mile south), The Burroughs (1 mile east), Hendon (1 mile south-east) and Kingsbury (1 mile south-west). Further out, we also cover London (9 miles south-east), City of Westminster (7 miles south-east), Marylebone (7 miles south-east), Kensington (7 miles south), St Pancras (7 miles south-east) and Shoreditch (9 miles south-east).
Local landmarks in Colindale
Typical jobs here are in homes near Sunny Hill Park, Saracens High School and Kisharon College, among other places. The nearest railway station is Hendon station, roughly 1 mile south-east. Other landmarks nearby include Edgware Community Hospital (1.3 miles north-west) and Brent Cross Shopping Centre (1.5 miles south-east). For a walk, there’s Darland's Lake and Parliament Hill.
What affects the quote in Colindale
The price is agreed before any work begins. It’s based on:
- The old material and how stubborn it is
- Any working-time requirements on site
- How many rooms, windows or areas are involved
- Whether the work is at height
Combining jobs into one visit is normally more efficient than separate visits. We will send you a clear quote for the lot.
What we need to know
What to tell us when you ask for a quote:
- Roughly how big the job is
- How we’d reach the joints
- Whether it has been sealed before
- Photos by email, if that’s easy
Want a quote for sand mastic? Please ring 0345 464 0079 or email us with a few details. You’ll know what we plan to do, and what it will cost, before any work begins.
Landlords, agents and businesses in Colindale
Mouldy or split sealant often shows up at the end of a tenancy, and it’s quick to put right between tenancies. We can quote for more than one property at once.
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance.
Signs you need sand mastic in Colindale
Timber frames move with the seasons. The movement cracks the mastic over time.
It’s worth asking for a quote if you see:
- Tired mastic found when preparing windows for paint
- Gaps between timber frames and stone or brick
- Mastic worn away on windows facing the weather
- Wind and rain getting in round a sash window
If you look after a building such as Colindale Primary School, its window and door frames need their mastic kept sound, just like a home’s.
Questions to ask before booking
- Is the old sealant removed completely?
- How much experience the applicator has
- Which colour the sealant will be
- How the joint is cleaned and prepared
Looking after it afterwards
Once the sealant has cured, a few habits help it last:
- Take care around the mastic when scraping paint
- Ask the planning authority about consent for listed or conservation-area homes
- Sort the mastic before the decorators arrive
- Have rotten timber repaired before new mastic goes in
Don’t touch or press the mastic while it hardens. It skins over quickly, but takes longer to harden fully.
Sound mastic protects the frame. Failed mastic lets water reach the timber, which can lead to rot.
Different surfaces, different methods
Stone surrounds
We take care not to mark the stone when the old mastic comes out.
Brick reveals
We rake out the old mastic and pack deep voids before the new mastic goes in.