1809.7 Prescriptive footings for light-frame construction.

[OSHPD 1R, 2 & 5] Not permitted by OSHPD. Where a specific design is not provided, concrete or masonry-unit footings supporting walls of light-frame construction shall be permitted to be designed in accordance with Table 1809.7. Light-frame construction using prescriptive footings in Table 1809.7 shall not exceed one story above grade plane for structures assigned to Seismic Design Category D, E or F.

TABLE 1809.7 PRESCRIPTIVE FOOTINGS SUPPORTING WALLS OF LIGHT-FRAME CONSTRUCTION a, b, c, d, e

NUMBER OF FLOORS SUPPORTED WIDTH OF FOOTING THICKNESS OF BY THE FOOTING f (inches) FOOTING (inches)

1 12 6

2 15 6

3 18 8

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm

a.

Depth of footings shall be in accordance with Section 1809.4.

b.

The ground under the floor shall be permitted to be excavated to the elevation of the top of the footing.

c.

Not adopted.

d.

See Section 1905 for additional requirements for concrete footings of structures assigned to Seismic Design Category C, D, E or F.

e.

For thickness of foundation walls, see Section 1807.1.6.

f.

Footings shall be permitted to support a roof addition to the stipulated number of floors. Footings supporting roof only shall be as required for supporting one floor.

(Ord. No. 7461, § 5, 11-10-2025)