<p>This Architectural Drawing is AutoCAD 2d drawing of RCC roof beam details in AutoCAD, dwg file. Reinforced concrete beams are <strong>structural members that support the transverse load which usually rest on supports at its end</strong>. Girder is a type of beam that supports one or more smaller beam. Contents: Types of Concrete Beams. RCC roof slab thickness is considered generally <strong>150mm (6 inches)</strong> for residential buildings and commercial buildings with reinforcement details as per design.</p>