The Edinburgh based firm was founded in 1904 but went into administration last month.
The full scale of its debts were revealed in an update from administrator Henderson Loggie posted at Companies House.
More than 100 suppliers and subcontractor have been hit by the demise of the firm which was working for main contractors including BAM, Balfour Beatty and Multiplex.
Henshaw offered full design, fabrication, supply and installation of building façades across various sectors, including commercial, residential, and public buildings.
It suffered financial pressures from additional costs in relation to legacy contracts, and significant main contractor delays on start dates for new projects, leading to reduced margins and trading losses.