It is possible that the person died some years ago and identification can only occur if police and ESR have a comparative DNA sample that the deceased's DNA can be compared to.
Neigbours told the Herald the owner was a recluse who went missing about a decade ago - but police would not speculate on the deceased's identity.
Police, however, confirmed they were not aware of a missing persons report that could be linked to the deceased.
Baldwin said police were focused on establishing the identity of the deceased, which includes identifying and speaking with former occupants and residents of the property.
Police had received a positive response from members of public contacting them with information, he said.
ESR scientists were also examining a large piece of concrete that has been removed from the property.
Police remain at the scene today while they carry out a scene examination.
A karakia is being arranged with the grateful assistance of local kaumatua.