This excerpt from the 1935-miami-dade-building-code details construction standards for Type III, IV, and V buildings, along with engineering regulations for loads and materials.
Type III Buildings Type III construction allows wood framing but restricts wood from passing through exterior walls (p. 125). Cornices and marquees must be of substantial incombustible materials (p. 125). Penthouses and skylights require one-hour fire-resistive-construction-requirements (p. 125). Combustible materials are permitted only where not prohibited by occupancy-classification or location, with vertical wood framing air spaces limited to seven feet (p. 125).
Type IV Buildings (Metal Frame) Defined as structures with steel, iron, masonry, or reinforced concrete frameworks and metal/incombustible exteriors (p. 125). Height is limited to 45 feet (55 feet on sloping ground) with a maximum of one story and a mezzanine (p. 125-126). Exterior walls must be galvanized iron or approved non-corrosive metal attached to horizontal supports no more than three feet apart (p. 126). Interior partitions must be incombustible (p. 126). Fireproofing of structural members is not required (p. 126). Roofs must be entirely metal or incombustible, though wood purlins are permitted for support (p. 126-127). Openings require metal doors/windows unless set back 16 feet from property lines (p. 127).
Type V Buildings (Wood Frame) Type V encompasses all wood-frame buildings not classified as Types I-IV (p. 127). Height is limited to 38 feet (two stories) or 45 feet on sloping ground (p. 127-128). Foundations must be masonry or reinforced concrete piers; for residential-and-accessory-occupancy-requirements (Group I) occupancies, piers must be at least 12x12 inches and reinforced (p. 128). Exterior walls require 2x4 studs at 16-inch centers, or 4x4 posts at 5-foot centers (p. 130).
Wall Coverings and Fire Stopping Exterior walls must be fire-stopped at floors and ceilings to limit concealed air spaces to seven feet, adhering to fire-separation-standards (p. 131). Weatherboarding must average 5/8-inch thickness (p. 132). Stucco requires metal lath reinforcement and two coats totaling 7/8-inch thickness (p. 133-134). Masonry veneer must be at least 3 3/4 inches thick and bonded to sheathing (p. 134-135).
Structural Components Floor joists tables specify maximum spans for Southern Yellow Pine and Douglas Fir based on size, spacing, and ceiling type (p. 136). Joists must have 18-inch clearance from the ground (p. 136). Roof rafters and ceiling joists spans are similarly regulated, with specific anchoring requirements for pitched roofs using collar beams (p. 137-138). Attached garages require one-hour fire-resistive-construction-requirements for ceilings and walls, with gravity-closing doors (p. 139-140).
Engineering Regulations Live loads are defined by occupancy-classification, ranging from 40 psf for dwellings to 250 psf for heavy storage (p. 141-142). Roof loads are 30 psf for low slopes (p. 142). Live load reductions are permitted for columns based on floor level and building type, influencing structural-load-calculations (p. 142-143). Wind pressure design values range from 25 to 45 psf depending on height (p. 143). Owners must post live load and seating capacity signs in commercial buildings (p. 144).
Related Concepts
- structural-load-calculations
- building-material-specifications
- construction-type-classifications
- fire-resistive-construction-requirements
- residential-and-accessory-occupancy-requirements
- fire-zones
- occupancy-classification