Greater London · London and the South East
Electronic Leak Detection in Sydenham Hill
Electronic leak detection to pinpoint holes in flat roof membranes for Sydenham Hill, from an experienced roof surveyor. Every survey comes with a written report and photos.
- Waterproofing to test before it is covered
- Punctures from foot traffic or tools
- Failed seams and laps
How electronic leak detection works in Sydenham Hill
Electronic leak detection, or ELD, finds holes in flat roof waterproofing membranes. It uses a small electrical current that passes through the membrane only where there is a breach. That lets us locate holes that are too small to see so your roofer knows exactly where to repair. The results come in a report with photos. If you’ve noticed damage from equipment installers and gaps at membrane joints, we can find out what’s behind it.
Across London, flat roofs are everywhere, from back additions and dormers to roof terraces, blocks of flats and offices. They’re covered in felt, asphalt, EPDM rubber, GRP fibreglass or single-ply membranes, and each fails in its own way. In Sydenham Hill, as anywhere in London, the right approach depends on what the roof is made of. Many older flat roofs are felt or asphalt, and many newer ones EPDM rubber or GRP.
Findings are set out part by part, from the coverings down to the gutters, each with a short note and a photo. It records what’s sound as well as what isn’t.
- Location
- Sydenham Hill (SE26, SE23, SE21)
- Region
- Greater London
- Cost
- Quoted for your roof
- Reports
- Written, with photos, emailed to you
- Survey days
- Weekdays and weekends
- Insurance
- Professional indemnity and public liability
- Call
- 07833 053749
- Last updated
- 27 October 2026
Why it’s worth a survey now in Sydenham Hill
Water trapped under a membrane can soak insulation and decking. Finding the breach sooner limits that. In Sydenham Hill, as in much of London, water from a roof defect can reach a neighbour’s home as easily as yours: a blocked parapet gutter or slipped slate can let water into the flat below or the house next door. Dealing with it early is far less disruptive.
What a survey costs comes down to the roof itself: its size, its height, how many sections it has and how safely it can be seen. Electronic leak detection is quoted for your roof, because the method depends on the roof.
Why book with us
- 5,000+ roofs surveyed
- Photographs and a written report every time
- Thermal imaging and drones used where they help
- Surveys seven days a week
Read how roof surveys are priced and two real surveys.
What we are asked to look at in Sydenham Hill
Joints and laps in a membrane can fail over time. A gap that is hard to see can let water in for months before it shows.
These are some of the problems a survey can pick up:
- Leaks through a covered membrane
- Leaks that return after repairs
- Holes around roof penetrations
- A flat roof leak that can’t be traced
Take an older house close to Church of St Philip the Apostle: flat-roofed rear additions and dormers added over the years are worth checking.
Choosing a roof surveyor
- How much experience they have with roofs like yours
- Whether the price includes VAT
- What follow-up you get after the report
- How soon the report will arrive
DIY checks: what’s safe
Inside, the loft is a good place to look, with care. Use a torch and stay on the joists or boards, and look for staining, damp timber or daylight coming through.
Watch the gutters in a downpour, from a window or the ground. Overflowing water can point to a blockage or a sagging run.
Landlords, agents and block managers in Sydenham Hill
Buyers’ agents can book surveys on behalf of their clients. Reports are emailed, so they’re easy to pass on.
Letting agents often book on a landlord’s behalf, with the report sent to whoever needs it. We agree a time with the tenant beforehand.
What electronic leak detection does not cover
Some things can’t be seen without opening up the roof, so a survey has limits:
- Build-ups without a suitable layer below
- Carrying out the repair work
- Sections we cannot safely access
If in doubt, ring 07833 053749 or send us an email and we’ll recommend the right survey before booking. What a survey covers and doesn’t.
Roof types and parts we check
- Roof terraces and balconies
- Green roofs
- Liquid-applied waterproofing
- Flat roof membranes
- Single-ply roofs
- Commercial flat roofs
Local flat roofs in Sydenham Hill
About 0.6 miles west lies Kingswood House, a reminder of how long the area around Sydenham Hill has been built on. If your home is one of the older ones, expect a mix of original materials and later repairs on the roof. Many homes in inner London are Victorian and Edwardian terraces, frequently with Welsh slate roofs. Behind many of their parapets sit butterfly roofs and valley gutters that can’t be seen from the pavement. Shared chimney stacks, party-wall upstands and lead work come with this kind of house. Next to the main roofs there is typically a flat roof somewhere, whether on an extension, a garage or a commercial unit.
Shop and office owners around Lewisham Shopping Centre may find that the flat roofs over shops and commercial units are worth checking before a leak, not after. Anyone responsible for a site like Kelvin Grove Primary School will know that large flat roofs, common on schools and other public buildings, need their outlets, upstands and coverings checked regularly.
Sydenham Hill is about 1 mile east of West Norwood, in Greater London. If you’re in Sydenham Hill, booking works exactly as it does anywhere else: a call or an email, a price, then a date. We cover towns and villages across Greater London, from the larger towns to small villages.
All of SE26, SE23 and SE21 is covered for electronic leak detection. Streets in the area include Grange Lane, Dallas Road and Lyall Avenue, all of which we cover. If you’re just outside Sydenham Hill, we cover West Dulwich (1 mile west), Sydenham (1 mile south-east), Crystal Palace (1 mile south), Dulwich (1 mile north-west) and Gipsy Hill (1 mile south-west). Larger places within reach include London (5 miles north), City of Westminster (7 miles north-west), Marylebone (7 miles north-west), Kensington (7 miles north-west), St Pancras (7 miles north) and Shoreditch (6 miles north).
Around Sydenham Hill
We work in homes and buildings around Long Meadow, The Wood House and Sydenham School, among other places. Sydenham Hill’s nearest station is Sydenham Hill station, about 0.5 miles west of the centre. A little further out are Horniman Museum and Gardens (0.6 miles north-east) and Lewisham Shopping Centre (3.2 miles north-east). Not far away are Knight's Hill and Dulwich Upper Wood.
Nearby places to Sydenham Hill
Other services in Sydenham Hill
Sydenham Hill questions
Is Sydenham Hill in the area you cover?
Yes, Sydenham Hill is within the area we cover. Our area covers London and the South East. You can ring 07833 053749 or email us with the address and a few details.
Is parking a problem for a survey in Sydenham Hill?
London parking needs a little planning, so let us know about permits, bays or a driveway as you book. The visit is then planned around what’s available.
What’s the best way to book?
It is easiest to call 07833 053749 or drop us an email. Give us the address and a few details about the roof, and we’ll take it from there. We survey on weekdays, Saturdays and Sundays.
Does the weather affect the survey?
Light rain doesn’t usually stop a survey, and it can even help show where water is getting in. High wind or heavy rain can stop drone flights and make roof access unsafe, so if conditions are not right we will arrange another day with you.
Can you find leaks on a covered flat roof?
Sometimes. It depends on the build-up and the layers above the membrane and parts may need to be lifted. We will discuss it before we quote.
What do I do with the report?
The report comes by email, and what you do next is up to you: use it with a seller, an insurer, a roofer or a managing agent.
Do you look in the loft space?
Yes, where the survey calls for it and there’s safe access. We look for staining, damp, daylight and signs of movement.
How it works
Once we have finished looking, we write up our findings as a written report with photographs. On timing, it typically takes a length of time set by the membrane area and the build-up, and we’ll give you a guide when quoting. In converted houses and mansion blocks, the loft hatch is often on a shared landing. Where that’s the case, access needs agreeing with whoever controls that landing. Everything else is planned around the building, not the postcode.
- We start with what you know about the roof and the leak.
- The roof is assessed for suitability first.
- The test method is chosen to suit the roof.
- We test the roof and locate any breaches.
- A report with photos shows where each breach is.
How to prepare
- Note where any stains or damp appear
- Jot down any questions you want answered
- If you are buying, check with the agent that we can get in
How to book
You can call us seven days a week. To book or ask a question, ring 07833 053749 or drop us an email.