Clause 5.2 defines when the ductile detailing provisions of IS 13920 become mandatory. All RC buildings in seismic Zones III, IV, and V must comply regardless of height. In Zone II, the code applies to buildings exceeding 5 storeys or 15 m height. This is a significant scope clause that determines the universe of structures requiring seismic ductile detailing.
Key Requirements
•All RC moment-resisting frame buildings in Seismic Zone III, IV, and V shall comply with IS 13920
•In Seismic Zone II, buildings with more than 5 storeys or height exceeding 15 m shall comply
•RC buildings with shear walls as lateral load resisting system in Zone III, IV, V shall comply
•Flat slab buildings in Zone III, IV, V are not permitted unless combined with moment-resisting frames or shear walls conforming to this code
•The provisions apply to monolithic RC construction; precast construction has additional requirements
Reference Tables
Applicability of IS 13920 by Seismic Zone and Building Type
Seismic Zone
Building Type
IS 13920 Applicable?
Zone V
All RC buildings
Yes — mandatory
Zone IV
All RC buildings
Yes — mandatory
Zone III
All RC buildings
Yes — mandatory
Zone II
Buildings > 5 storeys or > 15 m
Yes — mandatory
Zone II
Buildings ≤ 5 storeys and ≤ 15 m
No — ordinary detailing per IS 456 sufficient
Height is measured from the base of the building to the top of the roof slab. Storeys include basement storeys.
Practical Notes
✓Most urban construction in India falls in Zone III or higher, making IS 13920 compliance effectively universal for RC frame buildings.
✓Even in Zone II, many commercial and residential buildings exceed the 5-storey/15 m threshold, so always verify applicability early in the design process.
✓The 2016 edition significantly tightened requirements compared to 1993 — projects designed under the old code may not meet current standards if modified.
Common Mistakes
⚠Assuming IS 13920 does not apply in Zone II without checking the storey count and height — many Zone II buildings do require ductile detailing.
⚠Ignoring the applicability of IS 13920 to shear wall buildings and only applying it to frame structures.
⚠Using the 1993 edition provisions (IS 13920:1993) for new construction — the 2016 edition is the current standard with stricter requirements.