There is more speculative industrial floorspace under construction in the North West than any other region of the UK, according to a report by King Sturge.
The property adviser's UK Industrial and Distribution Floorspace Today study says the North West has 13.6% of the UK's speculative floorspace under construction.
This compares to 13.1% in Yorkshire and 12.6% in the East Midlands. The West Midlands accounted for 10.8% while Greater London had 10.7% of the total.
The report covers the first six months of 2007, during which period available space reached 228.6m sq ft in the country as a whole, a rise of 4.5% on the previous half-year.
The North West's traditional dominance as a manufacturing centre has left it with a lot of former factory space now being acquired and converted for distribution, trade counter and light industrial use. There has also been a spate of large sheds being built in recent years by Cheshire-based Gladman, Gazeley and others.
Tim Johnson, King Sturge's head of industrial agency, said: "The increase is due to big shed speculative development, the closure of manufacturing premises and the increase in secondhand warehouse space as a result of ongoing consolidation or expansion by others.
"We are generally not concerned about the increase in vacancy but, where product is in secondary locations, it could struggle."