New boiler installation in north and east London

In England, the Boiler Plus standards have applied since April 2018. A new gas boiler must reach at least 92% ErP efficiency and come with a timer and room thermostat. A new combi must also have one extra energy saving measure: weather compensation, load compensation, smart controls with automation and optimisation, or flue gas heat recovery.

The installer must notify the work to the local council within 30 days, and you then receive a Building Regulations Compliance Certificate (Gas Safe Register). Building Regulations also expect a carbon monoxide alarm when a new or replacement boiler is fitted (Approved Document J).

In a mid terrace in Hackney or Walthamstow the boiler often has to flue out through the back wall or the roof. In a flat, it may need a long horizontal flue across a ceiling. Where a flue runs inside a ceiling or boxing and cannot be seen, inspection hatches are needed so it can be checked (HSE flues in voids).

The flue terminal outside has to sit a safe distance from windows, doors, vents and boundaries, and those distances come from the boiler maker's instructions. In tight London back yards and passageways, a plume kit can carry the steam away from a neighbour's window. If you are doing a loft conversion, plan the dormer and rooflights around any existing flue.

Thames Water's 2025 reports put average hardness at 258 to 278 mg/l across north and east London zones. Industry guidance under BS 7593 and the Domestic Building Services Compliance Guide says that where hardness is over 200 ppm, the water feeding the boiler's hot water side should be treated, for example with a scale reducer (Fernox summary). The system should also be cleaned and dosed with inhibitor, and a filter fitted, so the new boiler does not inherit sludge from old radiators.

A combi heats water on demand and suits most flats and smaller houses. A system boiler with a hot water cylinder suits homes with two bathrooms in use at once, which is common in the interwar semis of Enfield, Finchley and Gants Hill. A regular boiler with tanks in the loft is still found in older houses. Changing type adds pipework, so the survey looks at what you have and how you use hot water.

Most homes in Tower Hamlets, Camden and Islington are flats, and many flats are leasehold. A like for like boiler swap in the same place is usually straightforward. Moving the boiler, adding a new flue through an outside wall, or running a flue through a shared roof can need the freeholder's consent under your lease. Check before you book the installation date. In blocks with a managing agent, ask whether there are rules on flue positions or working hours. A good survey notes these points so the job is not stopped halfway.