The electrical contractor had just signed a contract with Mace for the Chichester House office project in Holborn, London and was working on Hampton and Twickenham Academies for Leadbitter.
An industry source said: “Most of the firm’s 120 staff and agency workers have been taken on by main contractors or found work elsewhere.
“But I reckon about a third of the workforce will be hit.”
The £6m firm worked for first tier building services firms like SES, Gratte Bros and N G Bailey.
Alba is understood to have suffered because of two problem contracts last year and was trading through the debt when it lost support from its main private investor.