Police cordoned off the house yesterday while forensic staff from Environmental Science & Research examined the scene.
Other flatmates at the weatherboard bungalow in King St South were being questioned by police yesterday.
Lynch said detectives were receiving "good co-operation" from the other residents.
A post-mortem examination on the dead man was to be carried out today.
Neighbours in King St South told the Herald on Sunday that the house was sealed off with police tape and police officers were "all over" the property yesterday.
They described it as "a party house" where groups of teenagers often drank into the small hours and were often visited by police.
"There were police there the other morning making them pick up broken bottles, which I thought was bloody good," one neighbour said.
Tenants frequently came and went from the property.
"It was always a noisy house but it had been quiet for a couple of weeks and we thought maybe they had moved on but then this," said another neighbour.
Another neighbour had seen the police tape and was concerned.
"I have been waiting to hear the knock at the door from police either asking questions or giving answers but no one has been around.
"I want to know what is going on."