An extended ban on evictions will fail to prevent a damaging increase in homelessness without urgent emergency measures to protect renters, according to a coalition of church leaders, councils and charities.

Renters in England and Wales were given a reprieve last week when the ban, initially due to come to an end this weekend, was extended for a month. However, there are already warnings that the ban is masking a snowballing problem of rent arrears among those hit by the coronavirus pandemic.

Around 486,000 households are paying more than half their income on rent, according to the District Councils’ Network. This includes 108,000 lone parents and 100,000 people aged between 16 and 24.

There are calls for more legal protection for renters, as well as grants and loans for those who have been left in trouble by the pandemic.

David Walker, the bishop of Manchester, is among those warning that the ban extension “does not provide the long-term plan our nation needs, if we are to prevent homelessness rocketing once the rules change back, and avoid piling further pressure on low-paid workers to flout the coronavirus regulations”.

“If we fail to seize this opportunity,” he said, “not only will great personal suffering be caused to Britain’s most vulnerable households, we will also face a far more expensive task: rehousing people in temporary locations; and rehabilitating those whose health and wellbeing have been unnecessarily compromised through rough sleeping.”

Homelessness charity Shelter said that a third of calls from private renters to its emergency helpline since March were from people worried about losing their current home, while 42% were considered at risk of homelessness.

“The government must not waste this precious time that it has bought itself,” said Polly Neate, its chief executive.

“Once parliament resumes, judges must be given extra powers to stop renters losing their homes because of rent arrears caused by coronavirus. And longer term, we desperately need major reforms to make renting fairer, affordable and more secure.”

Giles Archibald, the leader of South Lakeland district council in Cumbria, also said now was the time for a long-term plan to be put in place. “Nearly half a million households who spend over half their income on private rent are at most risk of eviction as a result of the economic impact of the coronavirus pandemic,” he said.

“For now those families can rest assured they won’t lose their homes. In the meantime, government needs to work with councils to develop a plan to support tenants and landlords for once it is lifted.”

Landlords have warned that they are being left powerless and financially vulnerable as a result of the ban, warning that they are effectively footing the bill “for government failure”.

Housing secretary Robert Jenrick said that the government had introduced extra protection for renters, including a six-month notice period before evictions proceedings could start. He also said that courts had been told that when the ban ends, they should prioritise “the most egregious” cases.