Secondary Stair (Non-Required Stair)
Staircase without a building-code escape-route function.
A secondary stair is one that does not qualify as a required stair under building regulations. It serves as an additional route, for instance to attic storeys or galleries, and is subject to less stringent dimensional requirements. DIN 18065 permits rises up to 210 mm and a stair width from 50 cm for non-required stairs in single-family houses.
