Corrugated sheeting, corrugated roof sheets Corrugated Sheeting Corrugated is the traditional and familiar S-Rib profile for roofing and cladding applications. It is the oldest and most commonly used roofing profile because of its easy handling and fixing properties and related strength. The S-rib is derived from sinus curve and offers very strong and structural properties. Structural Guidelines Corrugated roof sheets are available in a wide range of materials displaying various structural properties. It should be noted that the load span characteristics are only to be used as a broad guideline, as purlin spacing is also dependant on other factors such as the prevailing winds in a particular area, snow during winter periods, the presence of dust and other particles in industrial areas, the type of structure that is being erected, etc. We therefore recommend that an engineer be consulted to determine the purlin spacing for a specific application. Roof pitch When using Corrugated, the recommended minimum pitch for roof slopes in excess of 15 m is 12.0° and for slopes less than 15 m is 10°. When Corrugated roof sheets are end-lapped the roof pitch should be taken into account. The minimum end laps for roofs pitches in excess of 15° is 150 mm and for other roofs a minimum of 250 mm is recommended. End laps for side sheeting should be at least 100 mm. It is recommended that end and side laps on low pitch roofs be sealed to ensure water tightness