Das NieDierländIstcHey roofing company Troelstra & Die Vries, founded in 1930, became part of the international SOPREMA Group in 2007. With this acquisition, the Heyt company gained access to a wider product range and experts on Heyt's expertise in waterproofing and insulation. Since October 1, 2016, Die NieDierländIstcHey branch has been operating under the name SOPREMA BV.