Electric Shower Installation in London: Do You Need a Plumber or an Electrician?
Electric shower installation is one of the most common jobs in London homes where mains water pressure is sufficient to run a power shower without a pump. It is also one of the most commonly misunderstood in terms of which trades are required. An electric shower installation in London requires both a plumber and an electrician, or a single engineer who holds qualifications in both disciplines. This guide explains the division of work and the Building Regulations requirements that apply.
Why an Electric Shower Needs Both Trades
An electric shower is a self-contained unit that takes cold mains water and heats it instantaneously as it passes over an electric heating element. Unlike a mixer shower, which draws hot water from the boiler or cylinder, an electric shower needs only a cold water supply pipe and a dedicated electrical circuit. Because the unit involves both a water connection and a high-current electrical connection, the installation crosses two distinct trade boundaries. The water supply connection is plumbing work, and the electrical circuit is electrical work. In London, both categories of work are subject to Building Regulations requirements and in practice require appropriately qualified and registered tradespeople.
The water supply side of an electric shower installation involves connecting a 15mm cold water supply pipe from the mains or from a pressurised cold water distribution point to the shower unit inlet. The supply pipe must be capable of delivering the minimum flow rate required by the shower unit, which for most London homes is not a problem because electric showers are designed to work directly from the mains supply. The plumber will also fit the waste pipe from the shower tray or enclosure, connecting it to the existing soil and waste system with the correct trap to prevent odours. If the shower is being installed in a new location that requires new waste pipe runs, the plumber will plan the route to maintain the required fall and to connect to the nearest available waste stack.
The Electrical Work Required for an Electric Shower in London
The electrical connection for an electric shower in London is not a standard plug-in appliance connection. Electric showers are high-power appliances, typically between 7.5kW and 10.8kW, which means they require a dedicated radial circuit from the consumer unit with a cable and circuit breaker rated for the full load current. A 10.8kW shower, for example, draws around 47 amps at 230 volts, and the circuit must be wired with 10mm cable protected by a 45-amp or 50-amp circuit breaker or fuse. This work must be carried out by a Part P qualified electrician, who must notify the work to the local authority under the Building Regulations Competent Person Scheme. The electrician must also install a ceiling-mounted pull-cord switch in the bathroom as the isolation point for the shower circuit, because standard wall-mounted switches are not permitted in zones close to water in a bathroom.
The electrical installation work must comply with BS 7671, the wiring regulations that govern all electrical installation work in the United Kingdom, and with Part P of the Building Regulations, which covers electrical safety in dwellings. The electrician must issue an Electrical Installation Certificate on completion, and this document should be retained by the homeowner as evidence of compliance. In London, where a large proportion of the housing stock consists of older properties with aging consumer units and wiring, the electrician will assess whether the existing consumer unit has the capacity and the appropriate protective devices for the new shower circuit before starting the work. If a consumer unit upgrade is required, this adds to the cost and programme of the shower installation.
Using a Single Installer for the Whole Job in London
Some London installation companies employ engineers who hold both plumbing qualifications and electrical qualifications, including Part P registration, and these companies can offer a complete electric shower installation service in a single visit. This is the most convenient option for London homeowners and tenants, as it avoids the need to coordinate two separate trades and two separate visits. Prestige Engineers can advise on the best approach for electric shower installation across all London boroughs. When instructing separate trades, always confirm in advance that the electrician holds Part P registration and that both the plumbing and electrical work will be self-certified under the appropriate Competent Person Scheme to ensure that the local authority completion certificates are issued on completion.