He predicted an initial report would be ready by the end of the month. "We're just working through the financial statements and that will take some time."
The first public statements would likely be issued next week when he hoped receivers would have "a better understanding of the situation".
He met with staff yesterday morning. "That was to confirm we had been appointed and seek their co-operation while we work through the process - and staff have been very co-operative."
He confirmed worried creditors had already been in touch with PwC, emailing and calling directly.
"They're obviously concerned about the position of the companies. Our task is to get a clear understanding of the company and formulate a strategy of receivership."
Meanwhile, Christchurch earthquake victims awaiting repairs were yesterday reassured their work would be completed.
Vero and AA Insurance use MWH Mainzeal for residential repairs and rebuilds on quake-hit properties and they told customers that their domestic building projects' progress would continue as usual.
Prime Minister John Key said he didn't believe the 45-year-old company's collapse would affect the rebuild in Christchurch where it has about 90 staff.
If you have been caught up in Mainzeal's receivership, email newsdesk@nzherald.co.nz.