StairBox chief executive Alex Hancock will continue to lead the business and all employees will remain in their roles.
A Stoke-on-Trent-headquartered manufacturer and distributor of bespoke wooden staircases has been acquired by a building materials distributor and DIY retailer for £44m.
Ireland-based Grafton Group has snapped up StairBox, which was founded in 1994.
StairBox chief executive Alex Hancock will continue to lead the business and all employees will remain in their roles.
Hancock said: "These are exciting times for the whole team at StairBox, we have seen impressive growth over the last few years by investing in our business and providing the highest quality service and products to customers.
"There are so many benefits of linking up with Grafton, both in our operations, and also in our aspirations for the team and the future.
"Grafton has a strong track record of investment in the group and supporting management autonomy to achieve the best results.
"Our team, customers and supply chain will benefit from being part of the group which shares our strong values."
Gavin Slark, chief executive of Grafton, added: "StairBox is a dynamic manufacturing business with a best-in-class online solution at its core.
"It has an efficient production process, nationwide distribution and strong growth potential.
"The acquisition is in line with our strategy of acquiring specialist high quality businesses and we are delighted with this acquisition and the skills and experience that the management team will bring to the group, under the leadership of Alex Hancock."
The Midlands team of BDO LLP advised StairBox on the deal.
The business was advised by Roger Buckley, Matthew Goodliffe and John Stephan in the M&A team.
Buckley said: "As part of the Grafton Group, the size and scale of the opportunities for StairBox are significant.
"This deal is a real success story for Staffordshire, with a Midlands based growth story attracting such a strategic investor.
"We look forward to seeing the team go onto even greater success in this next chapter."
Matt Fleetwood and Mark Lupton from Manchester-based, Beyond Corporate provided legal advice to Stairbox
James McKay and Joe Abbott of Squire Patton Boggs acted for Grafton Group pl