Greater London · England
Streatham Hill Window Mastic
Specialist window mastic for Streatham Hill: the right sealant, proper preparation and a neat finish. Ask us for a quick quote.
- Cracked or shrunken mastic around the frame
- Old mastic that has gone black or come away
- White mastic on grey or black frames
When it is not the sealant
It helps to know what we can’t do too:
- Damp problems in the wall away from the window
- A frame that has rotted at the joint
- A door that needs adjusting, rehanging or new seals
Not sure which it is? You can call 0345 464 0079 or send us an email and we will tell you honestly.
What we seal
- Timber windows & doors
- Patio & French doors
- Aluminium frames
- Composite doors
- uPVC windows
- Window sills
About our window mastic in Streatham Hill
If you can feel air around a shut window, the gap is often at the frame. Resealing that joint can make a room feel noticeably less draughty. Where the air is getting in through the window itself, we will say so. Typical jobs include rain getting in at the frame or under the sill and white mastic on grey or black frames, across patio & French doors, timber windows & doors and uPVC windows.
London’s Victorian and Edwardian terraces were built with timber sash windows, and many still have them or their replacements. Either way, the mastic between frame and brickwork is what stops draughts and rain getting in.
The work is covered for a year after we finish. If there’s a problem with it, please ring 0345 464 0079 or send us an email.
- Place
- Streatham Hill (SW2, SW16, SW12)
- Region
- Greater London
- Cover
- 12 months on all our work
- Quote
- A clear price before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
When to call us in Streatham Hill
Timber windows bring their own problems. Old mastic gets painted over and cracks under the paint, and the wood moves with damp as well as heat.
Any of these means the joints need attention:
- Cold air getting in at the frame edge
- A bead that doesn’t match the frame
- Gaps where the sill meets the wall
- Rain getting in at the frame or under the sill
Streatham Hill is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book.
What to look for in a quote
- Which sealant they’ll use, and why
- How the colour is chosen
- Who does the work, and how experienced they are
- Are they insured?
Landlord and commercial work in Streatham Hill
In hotels, rooms out of use cost money, so the work can be planned room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
For anyone letting property in or around Streatham Hill, several properties can be quoted together. Send us the addresses and the work at each.
What window mastic looks like in Streatham Hill
In a converted house or block, who looks after the windows depends on the lease, so it’s worth checking before booking. Historic houses like Kingswood House (about 1.9 miles east) are a reminder that the area around Streatham Hill 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.
Rented homes near Streatham Hill station change hands often, and sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. Homes close to Church of St Margaret include some older properties, and the joint between an old wall and a newer frame is usually the first place rain gets in.
Streatham Hill is about 2 miles south of Stockwell, in Greater London. Homes, rented property, offices and hotels in Streatham Hill is covered for window mastic. Every job comes with our one-year guarantee. Our area takes in 764 places across Greater London, large and small.
Postcode districts we cover here for window mastic: SW2, SW16 and SW12. Window mastic is available to properties on Keymer Road, Romeyn Road and Palace Road and the roads around them. Streatham Hill sits on or near the A205, which makes travel easy. Neighbouring places we cover for window mastic include Tulse Hill (1 mile north-east), Hyde farm estate (1 mile west), Streatham (1 mile south), Grange Mills (1 mile west) and Clapham Park (1 mile north-west). Further out, we also cover London (4 miles north), City of Westminster (5 miles north), Marylebone (5 miles north), Kensington (5 miles north-west), St Pancras (6 miles north) and Shoreditch (6 miles north).
Local landmarks in Streatham Hill
In Streatham Hill, that means homes and buildings near City Heights E-ACT Academy, Streatham Common and The Holland Tringham pub, among other places. Streatham Hill has its own railway station: Streatham Hill station. A little further out are Tooting Bec Hospital (1.4 miles south-west) and Southside Wandsworth (3.2 miles west). Open spaces near Streatham Hill include Battersea Park Lake and Knight's Hill.
FAQs for Streatham Hill
Is parking a problem for a job in Streatham Hill?
In much of London, parking needs planning: a visitor permit or a bay close to the door helps a lot.
I let a flat near Streatham Hill station. Can you help?
Yes. We work for landlords and letting agents as well as householders. You can phone 0345 464 0079 or drop us an email with the details for a clear quote.
Do you do commercial work?
Yes. Larger jobs can be planned room by room or area by area to suit the site.
What information do you need?
The location, the problem and the rough size of the job. If you can, email a few photos.
What does window mastic cost?
The cost depends on the size of the job, access and how much old sealant has to come out. Ask us for a quote and we’ll talk you through it.
Are you ARBOMaster approved?
Yes. We are an ARBOMaster approved applicator.
Will it make a mess?
No. The area is protected while we work and cleaned up afterwards.
Do you come to Streatham Hill?
Yes. From our base in Crawley, we cover South East England, London and all of Scotland, Streatham Hill included.
Should I try it myself first?
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is.
Sealing over old silicone is the commonest DIY error. Silicone doesn’t stick to old silicone, so it peels away and traps moisture behind it. All the old material has to come out first.
Places near Streatham Hill
What else we do in Streatham Hill
How it works
All our tools and materials come with us in the van. After a quick look at the joints together, the area is protected and the work begins. Most jobs take a few hours for a few frames, or a day or more for a whole house. In a London area like Streatham Hill, the main things to plan are parking and access: let us know about parking, the floor we’ll be working on and any lift or shared entrance.
- Each frame is looked over and we agree which ones need resealing.
- We remove the old mastic and clean the frame edge and wall.
- Deep gaps get closed-cell backing rod to set the depth.
- The new sealant goes on in white, brown, anthracite grey, black or clear to suit.
- We tool each bead neatly and check every joint is closed.
How to prepare
- Keep children and pets away from the work area
- On commercial sites, let us know about site rules
- Clear the area around the work
Get a quote
We quote each job on its own, so the first step is telling us about yours. Just phone 0345 464 0079 or email us with the details.
Advice
Quotes for window mastic in Streatham Hill
The price is agreed before any work begins. It’s based on:
- The number and length of the joints
- When we can work, for business premises
- How much old sealant there is and how hard it is to remove
- The number of rooms or windows
Doing several joints on one visit usually makes better use of the time than several visits. You will get one clear quote for the whole job.
Helping us quote
A few details help us give you an accurate quote. When you get in contact, it helps to mention:
- If someone has resealed it before
- Where the job is, and your postcode
- A few pictures by email, if you can
- The problem you’ve noticed
A good description makes for an accurate quote. Tell us where the job is, what’s wrong and how much there is, and add photos by email if you can.
Why deal with it now?
Draughts and leaks don’t always mean new windows. If the frames and glass are in good order, resealing the joints is often all that is needed. Problems with the glass or gaskets are for a window company, and we will say so. In London conversions, one flat’s bathroom is often above another flat’s ceiling, so a small leak from tired sealant can mean a neighbour’s ceiling and a lot of disruption. Dealing with it early is far simpler.
Homes and businesses are quoted the same way: the amount of work, the access and the products needed, along with when we can work on site. Call for a quick quote and we will explain what it covers.
Why us?
- We’re fully insured
- 180+ five-star Google reviews
- ARBOMaster approved applicator
- Colour agreed with you before we start
Take a look at how sealant jobs are priced and customer reviews.