R403.3.3

Section R403.3.3 is titled 'Drainage' and covers requirements for footing construction. The requirement for frost-protected shallow foundations to have final grade be sloped in accordance with another section of this code, and where soils are of a certain type, for the gravel or crushed stone below horizontal insulation to drain to specific locations is established. The purpose of this section is to prevent structural failure (due to loss of frost-protection).

The model shows a section of a shallow foundation with adjacent grade sloping away, and the stone below the horizontal insulation extending to daylight which allows water to drain. (Fill is not shown for clarity).