Travis Perkins is cutting 600 jobs and closing more than 30 branches as it warns of "uncertain" trading in the year ahead.
The builders’ merchant, which owns the Wickes brand, said those affected had already been informed.
The job losses come across its trade brands such as Travis Perkins, Benchmarx, and plumbing and heating businesses BSS and PTS.
The company said it hoped to relocate some of the staff.
Wickes – and its other consumer-facing business Toolstation – are not affected.
Ten smaller distribution centres will also close under the plans.
The company’s chief executive, John Carter, said: It is still too early to predict customer demand in 2017 with certainty and we will continue to monitor our lead indicators closely.
Given this uncertainty we will be closing over 30 branches and making further efficiency-driven changes in the supply chain, resulting in an exceptional charge of £40-50m this year.
While it did not mention the UK’s vote to leave the EU specifically and the resulting collapse in the value of the pound, the FTSE 100 firm made it clear it was seeking to cut costs to account for any drop-off in business.
The company said that while it was currently outperforming the market, its full-year profits would likely fall slightly shy of estimates.
The warning prompted a 7% fall in its share price in early trading.
It reported total sales growth of more than 3% for its third financial quarter – with growth across the board except in its PTS heating and BSS plumbing businesses, describing trading as not satisfactory.
Travis Perkins has taken on 4,000 staff this year amid an expansion of its best-performing outlets – with over 50 Wickes stores given an overhaul.
(c) Sky News 2016: Travis Perkins to axe 600 jobs and close dozens of branches