The main cause of the drop was prolonged periods of heavy rain during the normally busy summer months, the company said.
Sales to the public-sector and commercial end market, almost two thirds of Marshalls’ sales, dropped 6 per cent. But sales to the domestic end market, the remaining third of total group sales, fell twice as much, 12 per cent, against the year before.
However "decisive and proactive" actions taken last year in response to continuing market uncertainty, such as sale of properties and reduced capital spending, had cut fixed costs and net debt. Year-end net debt was £64m against £77m in 2011.
"Despite the challenging economic background, we continue to target growth markets within the public sector and commercial end market," said a spokeswoman, adding the group would focus on product innovation and good customer service.
"Street furniture, water management and internal natural stone flooring are seen as particular growth areas in addition to the continuing commitment to home, rail and retail," she said.
"In the domestic end market consumer confidence is reasonably stable, albeit at a low level. Continued development of the Marshalls Register is an area of focus. Domestic installers’ order books in late October were 8.7 weeks against 7.8 weeks a year before."
She added: "Marshalls has strong operational and financial flexibility. Capacity and the cost base are at a sustainable level for current market volumes. The group is well placed to take advantage of any improvement in market conditions."