DIY king B&Q's plans for a state-of-the-art flagship headquarters in Chandler's Ford is set to take a major step forward despite tough trading conditions.

More than two years ago the retail giant was given outline consent to redevelop land at Alldays House, Chestnut Avenue, which would bring together 1,500 staff under one roof.

Detailed plans for the first phase of the headquarters have been submitted to Eastleigh Council.

The building would consolidate B&Q's operations, including merchandising laboratories, which are currently scattered around Chandler's Ford and South-ampton.

The plans involve bulldozing part of the former Alldays House building.

The new building, covering some 9,224 square metres, will have a merchandising laboratory, training centre, meeting room suites, fitness centre, creche and kitchens, plus parking on three levels for 814 cars.

Detailed plans have yet to be submitted for phase two, which will include a new office building.

Planners have already imposed a series of conditions before B&Q can press ahead with the redevelopment. They include a new access roundabout on Chestnut Avenue and improvements to the Asda roundabout. There will also be new pedestrian crossings.

The complex will boast a number of environmentally-friendly features to cut carbon emissions, reduce water consumption and encourage natural habitats for wildlife.

B&Q will also come up with a traffic congestion-busting initiative, with a travel plan to reduce the number of cars travelling to and from its headquarters.

HR director Martyn Phillips said: "B&Q is committed to this area and wants to make sure that any building we create as a base is a long-term investment which does not have a negative impact on the environment. Our head office supports more than 320 stores around the UK. Bringing all our departments together under one roof will enable us to work together more easily."

The scheme could go before council planners next month.

B&Q owner Kingfisher, which employs 3,000 in Hamp-shire, is due to make a trading statement tomorrow.

It slashed its dividend by half and warned investors that things could get worse before they get better after unveiling its third successive fall in annual profit earlier this year.