Cupa first took a stake in Burton Roofing in 2008 and since then turnover has grown from £25m to £55m.
Cupa has now taken its shareholding from 85.6% to 100% by acquiring the remaining share capital from the estate of former owner Peter Burton.
Through its investment in Burton Roofing Merchants, Cupa has also acquired Brian Gow Roofing Warehouse, which has depots in Surrey and Kent.
Cupa chief executive Javier Fernández said: "With the addition of Brian Gow, Burton Roofing will significantly expand its local presence in southeast England, consolidating its position as one of the UK’s largest independent specialist distributor of roofing materials. Led by Paul Hattee, the company will operate 13 distribution centres across the UK, making it an attractive partner for the construction industry.
“Our continued investment in Burton Roofing, also demonstrates Cupa’s confidence in the long term prospects of the UK’s roofing materials market and Cupa’s firm commitment to internationalisation and growth."