Span Rating on APA Trademarked OSB Panels
The Span Rating denotes the maximum permitted centre to centre spacing of supports. It is particularly important for Rated Sheathing and Rated Sturd-I-Floor when the long panel dimension or strength axis is across two or more supports. See technical specifications for Sheathing, Rated Sturd-I-Floor and Structural 1.
What span ratings mean
- The trademark gives this as a fraction (in inches), such as 32/16. The number on left denotes the maximum centre to centre spacing of supports (in inches) when the panel is used for roof sheathing (sarking). Number on right denotes the maximum centre to centre spacing when the panel is used for subflooring.
- Sheathing panels with a roof span rating of 24 or greater may be used vertically or horizontally as wall sheathing over studs at 24 inch centres. Those with roof Span Ratings of less than 24 inches may be used vertically or horizontally over studs spaced at 16 inches on centre.
- Panels denoted as Wall-16 or Wall-24 have been specifically manufactured for use as wall sheathing over studs spaced at the designated distance apart.
- APA Rated Sturd-I-Floor panels are designated specifically for single layer flooring applications where a solid face is required. They are manufactured with Span Ratings of 16, 20, 24, 32 and 48 o.c.
Allowable uniformly distributed live load at maximum span
- 100 lbs/ft2 (1.48 kN/m2) plus a further 10 lb/ft2 (0.15 kN/m2) dead load.
- For Rated Sheathing a further 30 lb/ft2 (0.45 kN/m2) can be carried as snow load. Sheathing with a span rating of 48/24 or more can additionally carry a snow load of 35 lb/ft2 (0.52 kN/m2).
- Sturd-I-Floor 48oc can take a total load of 65 lbs/ft2 (0.97 kN.m2).