The Electrical Trades Union has described the collapse of a big Perth construction contractor on Thursday as the next in the race to the bottom of the construction sector.

About 400 staff were temporarily stood down on Thursday with up to two weeks pay owing after administrators were appointed to Henderson-based construction and maintenance contractor ECM.

ECM's Henderson office. Credit:ECM

Documents were lodged with ASIC on Thursday that Clint Joseph and Martin Jones from auditors KPMG had been appointed to administer the company.

It is understood ECM employed about 400 staff, mostly in WA, as well as a handful in Queensland and South Australia.