Private equity firm Quad-C Management agreed to acquire SEI Group, which distributes and installs insulation and specialty building products, from Narrow Gauge Capital. Financial terms were not disclosed. "We view SEI as an ideal platform to build a national business. We are excited to have the opportunity to partner with the SEI team to execute on our collective strategy and build a leading national installer of insulation and specialty building products," Matt Trotta, Quad-C Vice President.