Travis Perkins (LSE:TPK) said it is now "more uncertain" about its forecast for price inflation in building materials, having previously expected it to ease into the second half of the year.
Pricing is now expected to account for a larger share of sales growth this year than previously expected for the FTSE 250 company.
Cost inflation for the home improvement retailer should remain "manageable", it said, as sales jumped 13.6% in the first quarter to March 31 compared to the same period last year.
Although sales in the merchanting segment were up 17%, Toolstation sales were down 6.0% in the first quarter, with like-for-like sales down 11.9%, reflecting a tough comparison with the strong period a year ago.
The seller of building materials said its order books remain robust across the UK construction market and expectations remain the same.
The merchanting specialist businesses continues to see strengthening end-market demand from SME customers, including a growing interest in energy efficiency projects, while drivers for the Toolstation arm will "normalise" into the second half of the year once the pandemic rules are lifted.
"The group has had an encouraging first quarter and, although the wider economic backdrop remains uncertain, we are well placed to build on this positive start in the coming months," said Nick Roberts, chief executive.