Greater London · London and the South East
Blackfen Electronic Leak Detection
Electronic leak detection to pinpoint holes in flat roof membranes around Blackfen, with findings in writing and pictures to back them up. Weekday and weekend visits available.
- Water coming in under a flat roof
- Repairs that haven’t stopped the leak
- New roofs to check before paving or planting
How electronic leak detection works in Blackfen
Electronic leak detection works on many flat roof membranes over offices, units, blocks of flats and homes. It helps trace a leak you already have or to test a new membrane before it is covered. We quote for each roof based on its size and build-up. Testing can be carried out on weekdays, Saturdays or Sundays when conditions allow. Just ask about your roof. If you are worried about leaks that return after repairs and gaps at membrane joints, we can find out what’s behind it, on commercial flat roofs, single-ply roofs and green roofs alike.
London has a lot of flat roofs: rear additions, dormers, roof terraces and the roofs of blocks and offices. They’re covered in felt, asphalt, EPDM rubber, GRP fibreglass or single-ply membranes, and each fails in its own way. In Blackfen, as anywhere in London, the right approach depends on what the roof is made of. Older flat roofs are often felt or asphalt, newer ones rubber or GRP.
If any part of the flat roof membrane couldn’t be seen safely, we say so in the report. That way, it is clear what was covered and what wasn’t, and what we’d suggest next.
- Location
- Blackfen (DA15, DA16, SE9)
- Region
- Greater London
- Cost
- Quoted for your roof
- Report
- A written report with photos, by email
- Appointments
- Weekdays, Saturdays and Sundays
- Insured
- Professional indemnity and public liability
- Phone
- 07833 053749
- Page updated
- 27 October 2026
What happens if roof problems are left?
Chasing a leak again and again is frustrating. A report showing the breach points gives your roofer a clear target. Many older London roofs have only old felt under the slates, or no underlay at all, so once the slates or flashings let water past, little stops it reaching ceilings. Left alone, that means wet timbers and plaster, which is a far bigger job than the roof fault itself.
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. We quote electronic leak detection for each roof, as the method and time depend on the roof.
What you get with us
- Customer satisfaction of 98%
- More than 20 years surveying roofs
- Weekday and weekend surveys
- Drone and thermal imaging surveys available
See what a roof survey costs and what we found on two real jobs.
Electronic leak detection in Blackfen: local notes
With Danson House about 1.2 miles east, Blackfen sits in an area with a long building history. On older houses around here, roofs often carry the marks of earlier repairs, from replaced slates to new lead, and the council can say whether a home is in a conservation area. Outer London has lots of Victorian and Edwardian terraces with slate roofs, but also a great many interwar semis, often with hipped roofs in clay or concrete tiles. If your home in Blackfen is one of them, bay roofs, hips and later dormers each have their own details. Mixed in with those pitched roofs are a good many flat ones, over rear extensions, dormers, garages and shops.
If you live in an older home near Church of the Good Shepherd, the joins between later flat roofs and the old walls are where problems normally start. Blackfen is in London, so parking needs planning: let us know about parking bays, permits or a driveway as you book, as a space near the door cannot be promised.
Blackfen is about 2 miles east of Eltham, in Greater London. Houses, flats, blocks and commercial buildings in Blackfen can all book electronic leak detection, with a written report and photographs every time. Our Greater London coverage includes Blackfen and the places around it. We also survey roofs in London.
We cover every part of the DA15, DA16 and SE9 postcode area for electronic leak detection. You will find streets such as Days Lane, Gordon Road and Kent Avenue. We also cover the places around Blackfen: Falconwood (1 mile north), Avery Hill (1 mile west), East Wickham (1 mile north), New Eltham (1 mile south-west) and Longlands (1 mile south). Larger places within reach include London (9 miles north-west), City of Westminster (11 miles north-west), Marylebone (11 miles north-west), Kensington (13 miles west), St Pancras (10 miles north-west) and Shoreditch (9 miles north-west).
Around Blackfen
We work in homes and buildings around The George Staples pub, Harris Academy Falconwood and Shoulder of Mutton Green, among other places. Blackfen’s nearest station is Falconwood station, roughly 0.8 miles north-west. Nearby you’ll also find Broadway Shopping Centre (2.3 miles east) and Eltham Community Hospital (1.7 miles west). Not far away are Summer Hill and The Tarn.
When to book a survey in Blackfen
If a flat roof keeps leaking after patching, the hole may be elsewhere. Electronic testing helps pinpoint it.
Signs worth acting on include:
- Holes around roof penetrations
- Stains far from any visible defect
- Leaking laps in the waterproofing
- Leaks through a flat roof with no obvious cause
For landlords with property near Falconwood station, flat roofs on let property tend to be checked only when they fail, which is the costly way round.
Questions to ask before booking
- Whether the loft is part of the inspection
- Will the report include photos?
- Their drone registration, if they fly one
- What the survey won’t cover
FAQs for Blackfen
Will parking be an issue for a roof survey in Blackfen?
In much of London, parking needs planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
Does a conservation area affect roof work in Blackfen?
For listing, use Historic England’s list; for conservation areas, ask the council. It matters most if you are planning to re-roof in a different material.
How do you choose the testing method?
The method is chosen to suit the roof. Low-voltage testing typically needs a wet surface and high-voltage methods need the membrane dry and exposed.
Does ELD work under paving or planting?
It can be possible, depending on the roof. Covered roofs limit the methods we can use, so we check the build-up first.
Does this replace a RICS home survey?
No. We are experienced roof surveyors, and our survey covers the roof rather than the whole building. For the rest of the building, a RICS home survey is a separate job.
Does electronic leak detection work on all membranes?
It depends on the membrane and the build-up. Share any details you have and we’ll confirm suitability.
Is this an asbestos survey?
No. Our report may flag materials that could contain asbestos, but only a specialist asbestos surveyor can confirm it. It may be present in buildings built or refurbished before 2000.
What this survey can’t tell you
Every survey has limits, and we’d rather be clear about that before booking. Bear these in mind:
- Areas we cannot reach or that can’t be tested
- Roofs whose membrane or build-up is not suitable
- How wet the insulation is
Not sure which survey suits your roof? You can ring 07833 053749 or drop us an email and we will tell you. The full list of what we check.
Roofs we survey in Blackfen
- Green roofs
- Flat roof membranes
- Liquid-applied waterproofing
- Single-ply roofs
- Commercial flat roofs
- Roof terraces and balconies
Also near Blackfen
What else we do in Blackfen
Roof by roof
EPDM rubber roofs
EPDM rubber roofs often last 30–50 years, but can still be punctured.
Green and ballasted roofs
Green roofs and ballasted roofs cover the waterproofing. Some methods can work through these layers but it depends on the layers.
Landlords, agents and block managers in Blackfen
Businesses and commercial landlords can book us too, including offices, shops and units. Larger roofs take longer.
Surveys can also be booked by buyers’ agents acting for a client. Reports are emailed, so they’re easy to pass on, photographs included.
How the survey works
We do not take risks to get a closer look. Everything that can safely be seen is inspected, and anything we can’t see is noted in the report. The survey normally takes a length of time set by the membrane area and the build-up, and we’ll give you a guide when quoting. London terraces rarely offer a view of the whole roof from one spot, so in Blackfen we work round the house, using the street, the windows, the loft and any safe vantage point behind it. Shared stairs or a basement flat? Let us know who holds the keys.
- First, we confirm which roof areas are included.
- The surface is prepared for the chosen method.
- Testing runs across the agreed area.
- We mark the breach locations in our records.
- You receive the results to pass to your roofer.
Before we arrive
- Make sure the loft hatch can be reached
- Keep pets in another room
- If the roof is shared, arrange access with whoever manages the building
Booking a survey
You can call us seven days a week. To book or ask a question, ring 07833 053749 or send us an email.