Hello My Suggestions --The upper rigid basement floor number will be -2 --The behavior coefficients of the structural system will be 7 and 8 respectively. Also -- Stairs braces are wrong a- For the spiral staircase, instead of bracing the ribs, lay at least 16-18 cm thick on the landing floor b- Support the other ladder on the beam, not on the ribs -- Take the ladder loads -- Let the K7 beam center the curtain Take it easy Ünver ÖZCAN