base_rail_profile_and_varies_endpoint_relationship
[inclined base rail has distinct paired profile edges; VARIES vertical leg links its reference region to the safety-tread surface]Refines local profile topology without certifying which base-rail face carries the height extension. Existing34-in/36-in witnesses reused, never promoted to tread-to-rail height.
Drawing notation: [inclined base rail has distinct paired profile edges; VARIES vertical leg links its reference region to the safety-tread surface]
Refines local profile topology without certifying which base-rail face carries the height extension. Existing34-in/36-in witnesses reused, never promoted to tread-to-rail height.
Calculated from: stair-companion1013b-img_1265-m025, stair-companion1013b-img_1265-m027