Merchant Heating Plumbing Supplies has undergone a £12.88 million management buyout.
HPS was set-up 10 years ago with capital from a small number of shareholders.
The company reported sales of £39.6 million – with £1.2 million profit – in 2010.
Managing director Ron Walker said: "We are especially pleased that 50% of our staff have taken the opportunity to invest in the company which reflects the amazing support and dedication the company enjoys from all its staff.
"We look forward to continuing the successful development of the company following our MBO and will continue to expand our branch network in the coming years where we can find the right people and suitable opportunities. I would also like to thank all our previous shareholders for their magnificent support during the first 10 years of HPS."