Wood Frame (Modern)

Wood frame (modern) structures tend to be mostly low rise (one to three stories, occasionally four). Stud walls are typically constructed of 2×4 or 2×6 inch wood members vertically set 16 or 24 inches apart. These walls are braced by plywood or by diagonals made of wood or steel.

Masonry Veneer

A wood-framed structure faced with a single width of non-load-bearing concrete, stone, or clay brick attached to the stud wall.

Heavy Timber

Heavy Timber structures typically have masonry walls with heavy wood column supports, and floor and roof decks are 5-7 cm tongue-and-groove planks.

Lightweight Cladding

Non-structural cladding and linings (e.g., fiber cement, plywood) used in lightweight construction that uses timber or light gauge steel framing as the structural support system.

Masonry

Use this option when the exterior walls are constructed of masonry materials, but detailed construction information is unavailable or unknown.

Adobe

Adobe construction uses adobe (clay) blocks with cement or cement-clay mixture as mortar. The roof consists of a timber frame with clay tiles or, in some cases, metal roofing.

Rubble Stone Masonry

Rubble stone masonry consists of low-rise perimeter load bearing walls composed of irregular stones laid as coursed or uncoursed rubble in a cement mortar bed, with floor and roof joists constructed with wood framing.

Unreinforced Masonry – Bearing Wall

Unreinforced masonry buildings consist of structures in which there is no steel reinforcing within a load bearing masonry wall. Floors, roofs, and internal partitions in these bearing wall buildings are usually of wood.

Unreinforced Masonry – Bearing Frame

Unreinforced masonry is used for infill walls of buildings with a bearing frame. In this structure type, the masonry is intended to be used not to support gravity loads, but to assist with lateral loads.

Reinforced Masonry

Reinforced masonry construction consists of load bearing walls of reinforced brick or concrete-block masonry. Floor and roof joists constructed with wood framing are common.

Reinforced Masonry Shear Wall (with MRF)

Reinforced masonry construction consists of load bearing walls of reinforced brick or concrete-block masonry. Reinforced masonry buildings with “Moment Resisting Frames” carry lateral loads by bending. “Shear Walls” are continuous reinforced brick or reinforced hollow concrete block walls extending from the foundation to the roof and can be exterior walls or interior walls.

Reinforced Masonry Shear Wall (without MRF)

Reinforced masonry construction consists of load bearing walls of reinforced brick or concrete-block masonry. “Shear Walls” are continuous reinforced brick or reinforced hollow concrete block walls extending from the foundation to the roof and can be exterior walls or interior walls.

Joisted Masonry

Masonry exterior walls with roof of combustible materials on non-combustible supports.

Confined Masonry

Confined masonry is a construction system in which plain masonry walls are confined on all four sides by reinforced concrete or reinforced masonry members. The walls themselves, however, carry all of the gravity and lateral loads.

Cavity double brick

An unreinforced masonry construction type composed of two layers of bricks

Reinforced Concrete

Reinforced concrete buildings consist of reinforced concrete columns and beams. Use this if the other technical characteristics of the building are unknown.

Reinforced Concrete Shear Wall (with MRF)

Building constructed with reinforced concrete columns and beams, as well as reinforced concrete floor and roof. “Moment Resisting Frames” carry lateral loads by bending. “Shear Walls” are continuous reinforced concrete extending from the foundation to the roof and can be exterior walls or interior walls.

Reinforced Concrete Shear Wall (without MRF)

Building constructed with reinforced concrete columns and beams, as well as reinforced concrete floor and roof. Reinforced concrete Shear Walls are continuous reinforced concrete, extending from the foundation to the roof and can be exterior walls or interior walls. This category typically consists of buildings with a concrete box structural system with shear walls. The entire structure, along with the usual concrete diaphragm, is typically cast in place.

Reinforced Concrete MRF – Ductile

Buildings constructed with reinforced concrete columns, beams, and slabs. Moment Resisting Frames carry lateral loads due to earthquakes by bending. This kind of structural system can sustain large deformations and absorb energy without brittle failure.

Reinforced Concrete MRF – Non-Ductile

Buildings constructed with reinforced concrete columns, beams, and slabs. Moment Resisting Frames carry lateral loads due to earthquakes by bending. These structures have insufficient reinforcing steel embedded in the concrete and thus display low ductility.

Tilt-Up

Tilt-up buildings are constructed with reinforced concrete wall panels that are cast on the ground and then tilted upward into their final positions. These wall units are then anchored to the foundation and attached to each other. The roof and floor decks are typically wood. More recently, the wall panels are fabricated off-site and trucked in. These buildings tend to be one or two stories in height.

Pre-cast Concrete

The pre-cast frame is essentially a post and beam system in concrete in which columns, beams, and slabs are prefabricated and assembled on site.

Pre-cast Concrete with Shear Wall

The pre-cast frame is essentially a post and beam system in concrete in which columns, beams, and slabs are prefabricated and assembled on site. Lateral loads due to earthquakes are carried by cast-in-place concrete “shear” walls.

Reinforced Concrete MRF

A building constructed with reinforced concrete columns, beams, and slabs. “Moment-resisting frames” carry lateral loads due to earthquakes by bending. Information on the reinforcing steels is not sufficient to determine the building’s level of ductility.

Reinforced Concrete MRF with URM

Reinforced concrete columns and beams form “moment-resisting frames” to carry lateral loads due to earthquakes. Unreinforced masonry walls are used as infills between the columns to add lateral load resistance, but are not intended to serve as gravity load-bearing elements.

Steel

Steel frame buildings consist of steel columns and beams. Use this if the other technical characteristics of the building are unknown.

Light Metal

Light metal buildings are made of light gauge steel frame and are usually clad with lightweight metal or asbestos siding and roof, often corrugated. They typically are low-rise structures.

Braced Steel Frame

Buildings constructed with steel columns and beams that are braced with diagonal steel members to resist lateral forces.

Steel MRF – Perimeter

Buildings constructed with steel columns and beams that use only the frame members on the periphery of the structure to carry lateral loads. The internal beams and columns only carry the gravity load to the foundation.

Steel MRF – Distributed

Buildings constructed with steel columns and beams to carry lateral loads distributed throughout the building. The diaphragms are usually concrete, sometimes over steel decking. This structural type is seldom used for low-rise buildings.

Steel MRF

Steel MRF buildings consist of structural steel columns and beams. Lateral loads due to earthquakes are carried by the “moment-resisting frames,” but the locations of the moment-resisting frames in the building are unknown.

Steel Frame with URM

Structural steel columns and beams form “moment-resisting frames” to carry lateral loads due to earthquakes. Unreinforced masonry walls are used as infills between the columns to add lateral load resistance, but are not intended to serve as vertical load-bearing elements. Sometimes the steel frames are completely hidden in the masonry walls.

Steel Frame with Concrete Shear Wall

Structural steel columns and beams form exterior frames, but the joints are not designed for moment resistance. Lateral loads due to earthquakes are carried by reinforced concrete “shear” walls. The concrete walls are continuous from the foundation to the roof.

Steel Reinforced Concrete

Structural steel sections (beams and columns) are encased in reinforced concrete. The encased structural steel columns are sometimes discontinued in the upper portions of the buildings, making the columns in the upper floor regular reinforced concrete columns.