J Sainsbury has revealed plans to step up its drive to increase floor space.

Justin King, the supermarket’s chief executive, aims to close the gap on market leader Tesco by adding 5% extra floorspace a year by 2011; at the moment it is increasing it by less than half that figure. Most of the expansion will be accounted for by new stores.

The construction programme will be overseen by the group’s recently appointed property director Peter Bagley, who joined from Boots.

The 5% target for 2011, which would be equivalent to about 25 mid-sized stores, contrasts with Sainsbury’s current practice. In 2005 the chain expanded floor space 2%, with almost a quarter of that growth coming from extensions.

King said the acceleration in growth was designed to add £2.5bn in sales by 2008. This would be equivalent to an 18% addition to the group’s present turnover of £16.4bn.