The UK’s housing associations are facing a pension deficit climbing north of £1 billion, according to the latest estimates, adding to their financial challenges as they try to raise money from investors and tackle the country’s drastic housing shortage.

The UK has more than 1,100 housing associations, which are not-for-profit groups set up to provide rental accommodation, often to low-income tenants. A total of 473 of them participate in the Social Housing Pension Scheme, which has a shortfall last valued at £1 billion in 2011.