The companies being sold are Deborah, Sierra Communications (which now incorporates Holgate’s business), Easy Access, Donohoe Scaffolding, Rent-a-Fence, Roankabin Holdings and Eventserv.

The operations are being bought by an acquisition vehicle called Millington set-up by entrepreneur Denis O’Brien for the deal.

The companies had a turnover of £140m for the year to April 30 2011 and made an operating profit of £7m.

More than 2,300 people are employed by Siteserv across the UK and Ireland.

O’Brien said: “I believe that Siteserv – with a workforce of over 2,300 – has the potential to grow and develop geographically in many countries.

“Siteserv has an excellent track record of winning new business and growing revenues in a competitive market.

“Our investment demonstrates our commitment to growing the business into the future, supporting its existing customer base, employees and expanding further in its core markets.

“We believe the team has a great opportunity to capture growth opportunities in the future”.

The completed deal will see Sitserv wound down as a publicly quoted company and any proceeds left after its debts are paid will go to shareholders.

Siteserv said only £4m would be left from the sale for shareholders after its debts were settled.

The company confirmed to the Stock Exchange today that its current debt levels were “unsustainable”.

Siteserv said: “Following completion, the Group will not have any revenue generating operating businesses.

“The Board has determined that it is in the best interests of Shareholders as a whole to return the net proceeds of the Proposed Disposal to Shareholders as efficiently and expediently as possible and to wind up the Company to facilitate the distributions to the Shareholders in a tax efficient manner.”

The Siteserv name will retained but Siteserv plc will no longer exist.

Brian Harvey, Chief Executive, Siteserv said: “We are delighted with the partnership we have built with our new partner and we believe that this will enable us to consolidate and strengthen the ambitions of Siteserv in Ireland, the United Kingdom and Internationally, both through organic growth and acquisitions.

“In addition I believe teaming up with a new partner will provide security and strength to our balance sheet and in turn provide confidence to customers and employees alike. We believe the team has a great opportunity to capture growth opportunities in the future”.