Ask the expert: Who should install solar PV panels?

The growth of solar PV installations on new build developments has brought with it a grey area of responsibility – who should be fitting the panels to the roof?

Many developers require roofing contractors to install solar panels to ensure warranties and insurance cover for water ingress under NHBC rules. Electrical contractors, meanwhile, connect, test and certify the complete system. On the surface, this arrangement appears efficient – the roof remains warrantied, and the electrical installation is tested and signed off by a qualified person. However, concerns arise when roofers, who are not electrically trained, find themselves working with equipment that may present significant electrical hazards.

Under the Electricity at Work Regulations 1989, Regulation 14 is clear: no person shall be engaged in any work activity on or near live conductors unless it is unreasonable for it to be otherwise, and then only if suitable precautions are taken. While solar panels are delivered with pre-fitted connectors that may seem simple to handle, they can produce dangerous voltages when connected in series. A string of modern panels, typically rated at around 450W each, can generate 14-15A at 40-50V DC, quickly adding up to system voltages in excess of 400V.

This presents a real safety risk. Without training, roofers may underestimate the danger of working with live DC systems. The ‘plug-and-play’ appearance of PV connectors can give a false sense of security, but the potential consequences of a short circuit, arcing or contact with live parts are serious.

So, should roofers be electrically qualified and competent? I believe, at the very least, roofers handling PV modules should undergo appropriate safety training to understand the risks of working with electrical equipment. However, there is a strong argument that the full installation of solar PV systems should fall under the scope of trained electrical contractors, ensuring compliance with BS 7671 and workplace safety regulations.

With solar technology now a standard feature of many new homes, it’s time for organisations such as NHBC and main contractors to revisit their policies. Clearer guidance is needed to balance roof integrity with electrical safety, ensuring that both trades work together effectively without exposing operatives to unnecessary risks.

cef.co.uk

Need some technical advice? Darren is here to help! Send your questions to info@electrotechnicalnews.com

This article appeared in Electrotechnical News September/October 2025 edition – read it here