A British startup which uses technology to prevent renters from living in cold, damp homes has raised fresh funds to expand as landlords belatedly try to tackle outbreaks of mould in crumbling social housing.

Switchee has secured £5m, split equally between an existing investor, Axa IM Alts, and Octopus Ventures, part of the group which includes household gas and electricity supplier Octopus Energy.

The company hopes to use the funds – which come on top of a £6.5m investment round led by Axa in May 2023 – to help hit a long-term goal of installing its technology in 1m UK social housing properties.

Switchee’s technology, which is used by more than 130 social housing providers, measures humidity, temperature and pressure and analyses data with the aim of preventing mould and lowering heating bills, as well as improving communications between tenants and landlords.

The quality of social housing has been in the spotlight since the death of Awaab Ishak, a two-year-old who died in 2020 after exposure to mould in the rented flat where he lived in Rochdale.

Tom Robins, the chief executive of Switchee, said the toddler’s death was an “absolute tragedy”. “There is a continual trend here of setting a much higher bar of expectation in housing standards, and we’re seeing landlords embracing that and looking for technology solutions that they can deliver a more efficient, effective service,” he said.

Robins said the investment represented a “real milestone” moment. “We see there is a moment as social housing in the UK moves from a reactive to a proactive model. There’s clearly the demand and challenges, so we wanted to make the most of that.”

The company hopes to right an “injustice” that “people that can afford to pay their heating bills had access to technology to reduce the cost … where people who couldn’t afford to pay their bills did not have access to that technology”.

Robins said, in one of the worst situations he had witnessed, a Switchee device had helped identify a damp home where a single mother and her daughter were living in the lounge and kitchen because the bedroom ceiling had collapsed. “They had been evicted for complaints in the past so they were terrified to tell their new landlord. The property was then gutted and redone completely,” he said.

The tech can also help to reduce the impact of home heating on the environment, and Switchee’s devices have been deployed through government-funded initiatives such as the Social Housing Decarbonisation Fund.

Robins said that revenues had been doubling for the last three years, reaching £10m in its last financial year. “We are for-profit but our focus is on scale rather than profit,” he said.

Edward Keelan, a partner at Octopus Ventures, said it had been attracted by the company’s B Corp status and focus on social housing and the environment. Axa is the company’s largest single shareholder.

Switchee was founded by Adam Fudakowski and Ian Napier in 2015 and has so far connected 35,000 devices in homes. Robins said he hoped to hit the target of reaching one million homes “in the next five to 10 years”.

Robins paid tribute to Napier, who took his own life in 2019. “His belief in this drive for change is a very important part of the DNA of the business. We wouldn’t be here today without him,” he said.