Hertfordshire sits just over the M25 from north London, and it's an easy drive from our office in Chiswick. The county has two garden cities, several post-war new towns, a big university in Hatfield and a lot of commuter-belt offices. Each one brings its own Legionella questions.
Garden cities and new towns
Letchworth and Welwyn Garden City were planned in the early twentieth century, and their cottage-style terraces and semis are now a mix of owner-occupied and rented homes. Stevenage, Hemel Hempstead and Hatfield grew as post-war new towns, with big estates of 1950s and 1960s houses and low-rise flats, many now let privately.
Homes of that age have usually been updated more than once. A common picture: a modern combi boiler in the kitchen, but the old cold water tank still sitting in the loft, half full and connected to nothing much. Or a downstairs toilet and basin added by a previous owner on a long branch that hardly gets used. Those are classic places for water to stagnate, and our risk assessment is designed to find them. Most fixes are simple and handled by our remedial works team.
Hatfield and student HMOs
The University of Hertfordshire makes Hatfield one of the busiest student rental towns around London. A lot of family houses have been turned into shared homes for five, six or more students. More people means more showers and a greater chance that someone gets exposed if things go wrong, and empty rooms over the summer let water sit.
If you let a shared house, check whether it needs an HMO licence and what your council asks for. Councils can add their own licensing schemes on top of the national one, and conditions vary. We've written up how Legionella fits into HMO licensing. A current assessment, plus a record of flushing empty rooms and descaling showers, makes renewals simpler.
Commuter offices and quiet floors
Watford, St Albans, Hemel Hempstead, Welwyn and Stevenage all have office buildings and business parks, many with tenants who've adopted hybrid working. Fewer people in the building means less water used. Upper-floor kitchenettes, shower rooms for cyclists and accessible toilets can go days without a tap being run. If your building has been half empty for a while, our post on reopening a building after closure is a useful checklist.
Office managers usually need two things from us: an assessment that reflects how the building is used today, and a clear written scheme of control saying who flushes what and how often. If your team doesn't have time for the routine checks, our Legionella maintenance service can take them on.
Schools and care homes
Hertfordshire has a large school estate, from village primaries to academies and independent schools. Long holidays are the main issue, so plan flushing for the closure and a full flush and temperature check before term. Care homes across the county need hot water kept hot for Legionella control and TMVs to stop scalds at the outlet, which means regular TMV servicing as part of the routine.
Water in Hertfordshire
Affinity Water supplies much of Hertfordshire, and Thames Water supplies some parts. Much of the county's water comes from the chalk aquifer, so it tends to be hard to very hard. Your bill or your supplier's postcode checker will confirm who supplies you. Hard water means scale in showers, taps and TMVs, so descaling is part of good practice here.
Getting to you
We reach Hertfordshire on the M25, then the M1, A1(M) or A10 depending on the town. Most visits are straightforward for parking, though St Albans town centre and the older parts of Hitchin and Hertford can be tight. If you have a few properties in the county, we'll try to group them on the same day.
Towns we cover in Hertfordshire
- Watford
- St Albans
- Hemel Hempstead
- Hatfield
- Welwyn Garden City
- Stevenage
- Letchworth Garden City
- Hitchin
- Baldock
- Hertford
- Ware
- Bishop's Stortford
- Cheshunt
- Hoddesdon
- Borehamwood
- Bushey
- Potters Bar
- Rickmansworth
- Harpenden
- Berkhamsted
- Tring
- Royston
See our Legionella FAQs for the basics, or go back to all areas.