Hertfordshire · London and the South East
Electronic Leak Detection in Lemsford
Find out what’s going on with the flat roof membrane before you decide what to do next. Electronic leak detection in Lemsford.
- Leaks that return after repairs
- Waterproofing to test before it is covered
- Damage from equipment installers
Electronic leak detection in Lemsford: what you get
ELD finds breaches in the membrane but not every way water gets in. Water coming through walls, copings, rooflights or plumbing will not show on the test. We’ll tell you if we think the leak is coming from somewhere else. The test shows breaches in the membrane, not water coming through masonry or around frames. The report makes clear what was and wasn’t tested. We will point you to the likely next step. We’re often asked to look into holes left by work on the roof and patched roofs that still leak, across roof terraces and balconies, single-ply roofs and flat roof membranes.
Some older homes in villages like Lemsford are listed or in a conservation area, and that can affect how an extension roof or dormer is re-covered. If you are planning work, check with the council first. Finding out what state the roof is in gives you the facts to plan with. Changes that affect a listed building’s special interest need listed building consent.
Every survey ends with a written report, with photos, emailed to you. It explains the condition of the flat roof membrane, the defects we found and what we recommend.
- Location
- Lemsford (AL8)
- Region
- Hertfordshire
- Prices
- Quoted for your roof
- Report
- Emailed report with photos and recommendations
- When we survey
- Monday to Sunday, daytime
- Insured
- PI and public liability insurance
- Telephone
- 07833 053749
- Last updated
- 27 October 2026
Surveys for landlords and agents in Lemsford
If the property is let, the agent or a tenant can let us in, at a time agreed beforehand. We survey on weekdays, Saturdays and Sundays, which helps when tenants work during the week.
For a freeholder or residents’ company, a roof report is a sound basis for a maintenance plan, with the most urgent items set out first.
How the survey changes by roof type
Single-ply membranes
Single-ply membranes are common on commercial and newer roofs. Laps and fixings are where holes often appear.
Bituminous membranes
Bitumen roofs can often be tested electronically, depending on what’s below.
Tips from our surveys
Small things make a difference. Some pointers:
- Act on new leaks promptly
- Check new waterproofing before handover
- Share any drawings of the roof
- Keep a note of leaks after rain
Once repairs are made, the roof can be tested again if you want to check them if the build-up allows.
Consider testing a new membrane before it’s covered. It is easier to find holes before more layers are added.
Lemsford: your questions answered
Will you come out to Lemsford?
Yes, Lemsford is on our map. A small place gets exactly the same survey as a big one.
Is my home in Lemsford listed or in a conservation area?
You can check whether a building is listed on Historic England’s list, and your council can tell you if it’s in a conservation area. If a home is listed, changes that affect its special interest need listed building consent, and in a conservation area re-roofing in different materials may need permission.
Is this an asbestos survey?
No. Our report may flag materials that could contain asbestos, but only a specialist asbestos surveyor can confirm it. Buildings built or refurbished before 2000 may contain it.
Is it a structural engineer’s report?
No. Visible signs such as deflection or sagging are recorded, but we do not provide calculations or an engineer’s opinion. The report will say if you need an engineer.
Do I need to be at home?
Someone needs to let us in if we’re looking inside or in the loft. Access is agreed with you when you book.
I live in a flat. Can you survey the roof?
Yes, as long as access is agreed. Roofs over flats are frequently shared, so whoever owns or manages the building needs to agree access. We can only inspect what we’re given access to.
When does the report arrive?
Each package has its own report time. Basic is within 48 hours, Standard is 24–48 hours and Premium is the same day. Mention any deadline when booking.
How we price electronic leak detection
What a survey costs depends on the time and equipment it needs. That comes down to:
- Features like valleys, chimneys, dormers and parapets
- If the survey needs thermal imaging or a drone
- The size of the roof
- The number of roofs, including extensions and garages
For a price for your roof in Lemsford, phone 07833 053749 or use the contact form and tell us about the roof. The price is agreed before a date is set.
Helping us price your survey
The more you let us know, the easier it is to price the survey. When you contact us, tell us:
- Anything about access we should know
- Where the property is, with the postcode
- When you need the report by
- Any photos you have, taken from the ground or a window
We survey roofs on any day of the week. To arrange a day that suits you, call 07833 053749 or email us.
What we’re asked to look at in Lemsford
Joints and laps in a membrane can fail over time. Small openings at laps can leak for months before it shows.
Typical things we are asked to look at include:
- Failed seams and laps
- Patched roofs that still leak
- New membranes needing a check before handover
- Water coming in under a flat roof
Take a building like Applecroft School: ponding and blocked outlets on a wide flat roof are worth catching before the next wet season.
Questions to ask before booking
- How they plan to inspect the roof safely
- Whether the price includes VAT
- What experience they bring
- Will they check the loft as well as the outside?
The survey, step by step
Time on site depends on the size and shape of the roof, but as a rough guide the survey takes longer on a large roof than a small one, with the construction of the roof playing a part too. You’re welcome to ask questions while we’re there. Somewhere like Lemsford needs a little journey planning: let us know about lanes, gates and parking. The roof is looked at from ground level, from windows, from the loft where there is safe access and from the roof where it is safe.
- First, you tell us about the roof build-up and where water is showing.
- The roof is assessed to see if electronic testing will work on it.
- The method depends on the membrane and what sits above and below it.
- We test the membrane and find where current is passing through it.
- The breaches are recorded with photos in a report for your roofer.
Before the survey
- For a flat or shared roof, check access with the freeholder or managing agent
- Dig out any old roof reports or invoices
- Make a note of anything you’d like us to look at
How to book
To arrange a survey, phone 07833 053749 or use the contact form with the address and what you’d like to know about the roof. You will know the price before anything is booked.
Advice
Towns and villages near Lemsford
Other services in Lemsford
Local flat roofs in Lemsford
Older houses in the South East often have slate or clay tile roofs, while many later estates have concrete tiles, and flat-roofed additions turn up almost everywhere. Mixed in with those pitched roofs are a good many flat ones, over rear extensions, dormers, garages and shops. Digswell House, about 1.9 miles north-east, is one of the historic houses in the wider area around Lemsford. If your house is among the older ones, expect a mix of original materials and later repairs on the roof.
Shop and office owners around Howard Centre may find that outlets and upstands on commercial flat roofs are the places to check before trouble starts. If you live in an older home near Church of St John the Evangelist, later flat-roofed additions are common on older houses, and their edges and upstands often show the first signs of wear.
Lemsford is about 2 miles west of Welwyn Garden City, in Hertfordshire. We provide electronic leak detection for homeowners, landlords and businesses in Lemsford and the surrounding area. Our area takes in places right across Hertfordshire, large and small. There is also a page for London.
We work across the AL8 postcode area for electronic leak detection. That includes homes and businesses on Mill Close, Lemsford Village and Great North Road. If you’re just outside Lemsford, we cover Stanborough (1 mile south), Coleman Green (2 miles west), Cooper's Green (2 miles south-west), Hatfield (2 miles south) and Smallford (3 miles south-west). Within a short drive, we also cover Watford (12 miles south-west), Hemel Hempstead (10 miles west), Stevenage (8 miles north), St Albans (5 miles south-west), Harpenden (5 miles west) and Hitchin (11 miles north).
Near you in Lemsford
Typical jobs here are in homes near Stanborough Park, Stanborough School and The Sun Inn, among other places. The nearest railway station is Welwyn Garden City station, roughly 1.2 miles east of the centre. Well-known places in the area include Queen Elizabeth II Hospital (2.1 miles south-east) and The Bunker at Hatfield Police Station (2.1 miles south). Green spaces nearby include Lemsford Springs.