The £500m-turnover contractor, whose UK head office is in Hertfordshire, has employed the help of a large City corporate finance firm to assist with the acquisition of a medium-sized contractor.
Building understands that Sisk is in negotiations with Cowlin Construction and Pearce Construction of Bristol, Midas Construction of Kingskerswell near Torquay in south Devon, and two firms in Cardiff.
Staff at John Sisk have been asked if they would be interested in taking up opportunities in the South-west.
Sisk managing director Pierce O'Shea said he could not name the companies that had been approached because of confidentiality agreements.
But he said Sisk had employed a corporate finance firm to look at broad range of companies in the area and to assist in an acquisition.
Where we move into depends on which firm has the best fit with us as a company
Sisk chief Pierce O’Shea
O'Shea said: "We as a company have agreed that we want to move into the Cardiff and/or the South-west region. Where we move into depends on which firm we acquire, which has the best fit with us as a company."
O'Shea said Sisk had grown organically in the past and if an agreement could not be reached with another firm, internal expansion was possible.
He said: "We are building up a reservoir of people interested in going [to the South-west] and working out how we would do, which could be through internal promotions." He said plans had been made for the firm's expansion.
On the subject of a Sisk acquisition, Midas chief executive Steve Hindley said: "It's not us."
However, he refused to be drawn on whether Sisk had approached Midas.
Spokespeople for Cowlin Construction and the Pearce Group denied any sale was in the offing.
Rumours circulated in the City last year that Pearce wanted to sell off its construction business and that it was linked to regional contractor ROK. Crest Nicholson sold the Pearce Group to a management team in December last year.