The SA Government is stepping in to build a road after a building company collapsed. 

Adelaide's southern housing expansion at O'Halloran Hill is set to receive a boost as the South Australian government pledges to construct a access road, rescuing prospective homeowners from a frustrating limbo.

The housing enclave at O'Halloran Hill was abruptly abandoned after the building company, Felmeri Homes, folded, leaving numerous houses unfinished.

A lack of basic services and a half-finished road has hindered progress, impeding the efforts of other builders to complete the homes.

Responding to the pleas of approximately 20 homebuyers caught in this predicament, the government has announced its intention to spearhead the completion of the internal roadworks.

Premier Peter Malinauskas, says the government's intervention was crucial.

"Builders can't get access to actually do the work to fix these houses up because there's no way to get access," Mr Malinauskas said.

Mr Malinauskas described the “particularly unique” situation as an “unacceptable state of affairs” that is not in line with typical practices, where roads are usually built prior to housing construction.

The government has disclosed an initial cost estimate of over $1 million for the road's completion, while also pursuing avenues for cost recovery from the developer and associated entities.