Define spacing, single span, continuous span, load bearing, dead load, live load, nominal fixing.
Spacing - centre to centre distance between structural members.
Single Span - The span of a member supported at or near each end without intermediate supports.
Continuous Span - The span of a member supported at or near each end with intermediate supports so that no span is greater than twice another.
Load Bearing - The purpose of a structural member to transfer loads imposed on a building to the foundations.
Dead Load - Load of the structure itself.
Live Load - Load from things that can be moved in and out of the structure.
Nominal Fixing - Normally accepted fixing requirements.