Masonry spans between bearing walls and is overlaid with fill. A flat roof surface is provided and is often overlaid with roofing. Includes two-way vaults and masonry domes.

Brick masonry vault (M. Lutman)

Brick masonry vault (M. Lutman)

Brick masonry double vault, Italy (S. Brzev)

Brick masonry double vault, Italy (S. Brzev)

Double vaulted masonry roof, Peru (S. Brzev)

Double vaulted masonry roof, Peru (S. Brzev)

Vaulted masonry roof, Italy (S. Brzev)

Vaulted masonry roof, Italy (S. Brzev)

Damage of masonry buildings with vaulted masonry roofs in L'Aquila earthquake, Italy (T. Schacher)

Damage to masonry buildings with vaulted masonry roofs in L'Aquila earthquake, Italy (T. Schacher)

All types of plant-based wall materials. Includes matting, palm, thatch, straw.

EWV_Assam_India_Rawal_1

Exterior walls made of matting (Ikra walls), Assam, India (People in Centre)

A structural irregularity that is observed in the elevation or section of the building (vertical plane). If more than one vertical irregularity is observed, the primary vertical irregularity is that deemed to be the most significant in terms of affecting the building’s seismic performance, and the secondary vertical irregularity is that deemed to be the next most significant.

CHV_USA_Brzev_3

Example of a reinforced concrete building with a vertical irregularity, USA (S. Brzev)

All types of roof covering made from lightweight vegetative material. Includes birch bark roof, split stem bamboo, thatched. Does not include planted 'green roofs' with soil and living plants.

RMT8_Assam_India_Rawal_1

Thatch roof covering, India (People in Centre)

RMT8_Cuba_Brzev_1

Thatch roof covering, Cuba (S. Brzev)

RMT8_Dominican Republic_BrzevS_1

Thatch roof covering, airport building, Dominican Republic (S. Brzev)

A structural irregularity that is observed in the elevation or section of the building (vertical plane). If more than one vertical irregularity is observed, the primary vertical irregularity is that deemed to be the most significant in terms of affecting the building’s seismic performance, and the secondary vertical irregularity is that deemed to be the next most significant. If there is only one structural vertical structural irregularity observed, the term "No Irregularity" will be used by default.