Ray O'Rourke, the chairman of Laing O'Rourke, has called for the "grunt" to be taken out of construction by modernising working practices.

Clarifying his comments that building sites were "no place for women", made at the British Council for Offices conference this year, O'Rourke said the industry should change its working practices.

O'Rourke said he wanted to reduce the on-site workforce by 60% over the next five years by improving their skills and adopting new technology.

He said: "Until we change the poor image and the prevailing culture and behaviour and take the ‘grunt' out of the current manual work practices through modern and smart methodology, we will not attract the talent and skills needed to deliver our projects."

But the chairman used a memo to staff to clarify that, at present, it was "unrealistic" to believe women and migrant labour could be used to fill skills gaps.

He said: "The reality of the industry today is that it is a tough physical and mental environment that stubbornly retains its old culture and values. In this context, I believe that construction sites are not a suitable, much less an ideal, environment in which women could work in manual labour jobs."

O'Rourke said significant numbers of women would not be attracted to the industry until site practices and culture radically changed.

Two weeks ago O'Rourke's comments that a building site was "not a place where women fit" caused an outcry, particularly from senior women in the industry.

The remarks, made during a seminar on industry resource problems in the build-up to the Olympics, led some women to question whether they would continue their working relationship with O'Rourke.

But O'Rourke stressed the company employs women throughout the organisation and that the number of women was increasing each year - 20% of the company's current graduate intake are women.