Birtley Cavity Lintels lack a baseplate and includes factory fitted insulation to reduce thermal bridging. The CB150 Cavity lintel range is hot dip galvanised following Fabrication and provides 50% more Zinc Protection than other approved coatings. Suitable for 150mm Cavity. Not suitable for point loads or concrete floors. The CB range is designed for ease of installation and to exceed the performance requirements of all existing standards.