Builders' merchant Travis Perkins has warned of lower-than-expected profits after suffering a slump in orders.
Same-store sales at its Wickes division tumbled 21%
The company, which bought the Wickes chain for £950m in 2004, said it had been hit by price-cutting among rivals and a dip in consumer confidence.
Travis Perkins said that market conditions had "worsened significantly" since mid-October.
Like-for-like sales at Wickes were down 9% in the four months to the end of October, the firm said.
That compared with a 6.2% decline in the 10 months to the end of October.
Travis Perkins said annual profits would be about £205m, down from the £225m previously forecast by analysts.
"We anticipate that this heightened level of price driven competition will continue into 2006 and will reverse some of the market share gains made up to August 2005," the company said.
Its monthly consumer confidence surveys showed a "marked deterioration" in expected workloads and order books.
"Accordingly, we expect trading conditions in merchanting to worsen more than usual through the winter period," it said.
This could result in an "extended shutdown" in the building sector over the festive season.
Travis has more than 970 outlets in the UK.