Rafter Spacing For Slate Roof

A metal roof must also allow for some overlap on each side of the panels which will reduce the effective width of the panel.

Rafter spacing for slate roof. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. 0 75 kn m snow load 0 9 kn. Rafters must be strong enough to hold the roof sheathing and the shingles. Surveyors and structural engineers utilise data from tables below to help calculate the correct size strength and centres of roof timbers for the required spans and loadings.

Usually 400 450 or 600mm but any value can be used up to 610mm max. For pitched roofs flat roofs and ceiling joists. Rafter and roof joist spacing is only one part of a complex roof design that works together to form a structure that meets building codes and can hold up the weight of the roof and roof load. In finished space insulation is placed between the rafter boards and drywall or other material is fastened to the face.

Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch. But they do tend to space rafters in one of several industry standard increments typically. Other imposed loads roof snow load and short term point load altitude not exceeding 100m. Surveyors span tables for designing roof rafters.

This is the distance between rafter centres. Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run. Typical rafter spacing codes will specify a minimum spacing of 16 inches 19 2 inches or 24 inches. Rafter boards are fastened to the ridge board at the peak and the top plate where they join the wall.

Wider panels allow for greater spacing between rafters. Rafter spacing is based on the width of the metal roofing panels. Builders aren t bound by standard rafter spacing measurements. As a general rule roofs that have a high human occupancy rate should be framed with rafters every 16 structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes.