The final sitting of the royal commission into institutional responses to child sexual abuse was packed to overflowing Thursday when Justice Peter McClellan walked into the room to a standing ovation.

Scores of survivors of sexual abuse, and the people who supported them, were there – from family to lawyers - alongside the Prime Minister Malcolm Turnbull and leader of the opposition Bill Shorten, applauded loudly as the commissioners took their seats for the final time in the Sydney hearing room.

The tissue boxes provided on the seats were passed around as Justice McClellan began his final address into the royal commission that began on November 12, 2012 when then Prime Minister Julia Gillard announced its creation.

Over the past five years, more than 15,000 Australians contacted the royal commission. Over 8000 of them spoke with a commissioner in a private session; for many it was the first time they had told their story. More than 4000 individual institutions have been reported as places where abuse took place. More than 2500 allegations had been reported by the royal commission to the police; many of them from private sessions. So far 230 prosecutions have been commenced.

"Many institutions we examined did not have a culture where the best interests of the children were a priority. Some leaders did not take responsibility for their institution's failure to protect children," Justice McClellan said.

Counsel assisting the Commission Gail Furness, SC presented a bound book called Message to Australia, made of messages from over 1300 survivors, to Dr John Vallance the NSW State Librarian, on behalf of the National Library. The book will be available in all state and territory libraries, and is a powerful testament to the trauma and tragedy of these stories.

But the elephant in the hearing room was all those who weren't there. The absence of the many hundreds, thousands more victims of sexual abuse, who found peace from their endless torture "the only way they knew how by taking their lives," as Joan Isaacs, one of the first to give evidence against the Catholic church four years ago said later outside the hearing room.

Those like Andrew Nash, who 43 years ago as a 13-year-old student at Hamilton Marist Brothers came home from school and killed himself in his bedroom. His sister Bernadette, who found him, and his mother Audrey were at Thursday's hearing, they later learnt he had been abused by one of the six confirmed paedophiles at the school.

"We had no idea, no inkling, so today is an emotional day," Mrs Nash said outside the hearing room.

Bill Shorten said a proper compensation deal for survivors was required but "that doesn't give them back a stolen childhood".

An Aboriginal smoking ceremony took place after the final session and the commission's recommendations will be presented to Governor-General Peter Cosgrove on Friday.