ISO 3 – Non Combustible (NC) Class 3B / NC-I (non-combustible) Buildings where the exterior walls and the floors and roof are constructed of and supported by metal, asbestos, gypsum or other non-combustible materials. Minimal combustible materials in the building construction Typical steel frame walls with masonry in-fill, brick veneer, metal sheathing, EIFS. Steel framing is load bearing portion of the building frame. AMBS (all metal building system) pre-engineered construction is common. Light steel frame ISO 3 smaller geometry with no interior building support columns. Heavier ISO 3 larger geometries with internal support columns and heavier roof framing. If multi-story, floors are commonly concrete on steel frame on steel deck.

 RI-pg1-r1-p3v2Roof deck and roof cover systems:

Roof deck and roof cover systems: *Steel deck -BUR (built up roof with gravel or modified bitumen) -Single-ply membrane -Lesser extent foam/spray applied roof which is typically applied over an existing roof cover – this is not considered a roof cover replacement. -Usually flat/low sloped Metal -Lap seam metal panel (exposed fasteners) –Standing seam metal panel (concealed fasteners) -May or may not be coated/sealed -May be gable, hip, flat or combination of geometries.  Roof anchorage: *Light steel frame ISO 3 may still incorporate clips, single wraps, or double wraps *Because of heavier construction with no wood framing in roof, roof to wall anchorage is typically an engineered bolted and/or structural roof connection. Toe nailing, Clips, single wraps, double wraps do not apply.

Examples: warehouses, manufacturing facilities

ISO  8:   A subset of NC Construction is Superior Non-Combustible Construction NC-II, also known as ISO 8 (Class 8AB). This shall apply to Non-combustible constructed buildings where the following additional conditions exist: Where the entire roof is constructed of 2 inches of masonry on steel supports; or, where the entire roof is constructed of 22 gauge metal (or heavier) on steel supports; or, where the entire roof assembly is documented to have a wind uplift classification of 90 or equivalent.