Accountants from Begbies Traynor are now running the south west specialist which turned over £25m at its peak and has been trading since 1985.
Black Horse employed 220 staff and the remaining 40 workers will be made redundant by the end of this month.
Among the full-time workers were 45 site gangs.
Begbies Traynor said the industry downturn had made it difficult for Black Horse to renegotiate financing with its banks.
Staff were paid for the week to December 9 by the company but wages after that plus any outstanding holiday pay will have to be claimed from the Government.
