Building Diagram Number

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2. Building Diagrams

Diagram 1A: Slab-on-Grade Without Fill

• Key Feature: Bottom floor at or above ground level on at least one side.
• Lowest Floor for Rating: Top of slab or lowest garage floor if applicable.

Diagram 1B: Slab-on-Grade With Fill

• Key Feature: Raised slab with fill at or above ground level.
• Lowest Floor for Rating: Same as Diagram 1A.

Diagram 2A: Full Basement

• Key Feature: Floor below ground level (subgrade) on all sides.
• Lowest Floor for Rating: Top of basement floor.

Diagram 2B: Subterranean Basement

• Key Feature: Fully underground with limited access points.
• Lowest Floor for Rating: Top of basement floor.

Diagram 3: Split-Level Slab-on-Grade

• Key Feature: Multiple levels at or above ground on one side.
• Lowest Floor for Rating: Top of slab.

Diagram 4: Split-Level Basement

• Key Feature: Partial subgrade floor below ground level.
• Lowest Floor for Rating: Basement slab.

Diagram 5: Elevated on Piers or Posts (Open)

• Key Feature: No obstructions below elevated floor.
• Lowest Floor for Rating: Lowest elevated floor.

Diagram 6: Elevated on Piers or Posts (Enclosed)

• Key Feature: Fully or partially enclosed area below elevated floor.
• Lowest Floor for Rating: Lowest elevated floor or enclosure floor, depending on conditions.

Diagram 7: Elevated with Walkout Basement

• Key Feature: Basement partially below grade with ground sloping away.
• Lowest Floor for Rating: Elevated floor above the walkout basement.

Diagram 8: Non-Elevated with Attached Garage

• Key Feature: Non-elevated floor with garage included.
• Lowest Floor for Rating: Floor of the attached garage or lowest enclosed area.

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