They say they've had to fight to get things moving.
Maryanne and Peter are frustrated no-one has been held accountable for the collapse of the building.
The four-year criminal investigation into the incident is in its final stages, police say, with a decision on whether charges will be laid expected within weeks.
In 2012, the royal commission of inquiry found serious errors by engineers, structural designers and the Christchurch City Council.
But Maryanne and Peter say it is hard for them to move on until they know if anyone will be held accountable for the deaths of their colleagues and friends.
However, they say it is important the job is done properly.
Investigators have interviewed more than 100 witnesses and raided the offices of Engenium Consulting Engineers, formerly Alan Reay Consultants, which designed the Madras St office block in the mid-1980s.
Maryanne and Peter say they fear the investigation will end in a similar way to the Pike River Mine tragedy, in which 29 men lost their lives.
- star.kiwi