He came across workmate Russell Smith as he made his way back to the entrance, and pulled him to safety, slowing his own escape down.
The pair were the only two to survive the blast.
Mr Rockhouse's brother Ben, 21, was one of the 29 miners whose bodies still lie inside the West Coast mine.
The humble hero received his medal from Governor-General Sir Jerry Mateparae at today's ceremony.
His family was in attendance, and were visually emotional, as Mr Rockhouse accepted his award.
"I'm pretty humbled about getting the medal... I'm just happy to be here, it's been a surreal experience," Mr Rockhouse told media following the ceremony.
"It feels a little bit strange still, receiving it. I still am proud to get it, but it is still on my mind about my brother and the rest of the guys on the ground."
He said he believed his workmates and his brother would be proud of him today.
"Hopefully they're looking down on me. That's something I always think about."
Sir Jerry said today's celebration was a chance to acknowledge the significant contribution a group of people had made to the country.
The investiture is the first of six to be hosted at Government House in Wellington this week.