Ask a London estates manager how many TMVs they look after and you'll often get a shrug. On a big healthcare or housing portfolio the honest answer can run into the hundreds, spread across buildings put up a century apart. That's the London problem in a nutshell: lots of valves, lots of different makes and ages, and water that's hard on all of them.
Why London buildings have so many TMVs
TMVs go wherever vulnerable people use hot water, and London has a lot of those places packed close together. Acute and mental health hospitals, community health centres, GP surgeries, private hospitals and day clinics, care homes, nurseries, special schools and supported housing all sit within a few miles of each other.
The buildings themselves add to it. A Victorian hospital block may have been extended three or four times, each phase with its own plumbing contractor and its own idea of which valve to fit. A 1960s estate might have a sheltered scheme on the ground floor with TMVs on every bath. A new-build block next door will have its own valves set to the Building Regulations bath limit. Every one of them needs finding, logging and testing.
Healthcare and HTM 04-01
NHS and private healthcare buildings work to HTM 04-01. In practice that means TMV3 valves, commissioning records, and in-service tests at intervals your Water Safety Group can justify. We follow the test in Chapter 11 of the D 08 supplement: supply temperatures, mixed temperature at full flow, cold isolation and the recovery check. Our HTM 04-01 and D 08 guide walks through it.
Private healthcare in London deserves its own mention. Clinics and consulting rooms are often in converted townhouses, fitted out by different contractors over the years. It's common to find TMV2 and TMV3 valves side by side, or a TMV feeding a thermostatic tap, which HTM 04-01 Part B says to avoid. Sorting that out is usually the first job.
Care homes, schools and housing
London care homes range from purpose-built blocks to big Edwardian houses with extensions on the back. HSE's guidance on hot water in health and social care sets a 44°C maximum for baths where vulnerable people could be at risk, and that's the figure inspectors will expect your records to show.
Schools and academy trusts often hold sites in several boroughs. Housing providers have sheltered and extra care schemes scattered across the city, where getting into each flat takes some organising. In both cases a single register that covers every building saves a lot of chasing.
Hard water and limescale
Thames Water supplies most of London. Parts of the north-west are on Affinity Water, parts of the south on SES Water and parts of the far east on Essex & Suffolk Water. Whichever it is, London water is mostly hard to very hard. To see the figures for a particular building, put the postcode into Thames Water's hardness checker, or the equivalent tool if you're on a different supplier.
For a TMV, hard water means scale on the thermostatic element, crusted strainers and a slower response when the cold is isolated. HTM 04-01 Part B notes that local water quality affects how often valves need checking, and in London that's a real factor. We descale as part of the service and note which valves scale up fastest, so the interval can be set from evidence. There's more in Hard water and TMVs: limescale, strainers and descaling.
Portfolios across the capital
Plenty of London organisations run ten, twenty or fifty buildings. We set those up as one register with one numbering system, then plan visits so a day's work covers sites that are close together. You get reports grouped by building, so each site manager sees their own valves and the estates team sees the whole picture.
Getting around
London driving takes planning. The whole city is inside the ULEZ, the centre has the Congestion Charge, and most inner areas have controlled parking zones. When you book, we'll ask about parking, loading bays, permits and any restricted access times. A few minutes on that saves a lot of carrying kit from three streets away.
Where we cover in London
Every borough, plus the Square Mile:
- City of London
- Westminster
- Camden
- Islington
- Hackney
- Tower Hamlets
- Southwark
- Lambeth
- Wandsworth
- Kensington & Chelsea
- Hammersmith & Fulham
- Ealing
- Hounslow
- Richmond
- Kingston
- Merton
- Sutton
- Croydon
- Bromley
- Lewisham
- Greenwich
- Bexley
- Havering
- Barking & Dagenham
- Redbridge
- Newham
- Waltham Forest
- Haringey
- Enfield
- Barnet
- Harrow
- Brent
- Hillingdon