1 Wall Type
2 Storeys Supported
4 Soil Condition (Sentence 3)
Gravel, sand, or silt · water table below footing
Halves minimum width per Sec.9.15.3.4.(3)
3 Joist Spans
Enter joist span per storey.
Minimum Footing Width
WALL
—
— mm
Enter joist spans above
Table 9.15.3.4
Min. strip footing widths (mm), spans ≤ 4.9 m
| Storeys | Exterior | Interior |
|---|---|---|
| 1 | 250 | 200 |
| 2 | 350 | 250 |
| 3 | 450 | 300 |
Formula — Sec.9.15.3.4.(2)
W = w × [ Σ sjs / ( storeys × 4.9 ) ]
W = min. footing width w = table value
Σ sjs = sum of joist spans 4.9 = ref. span (m)
Applies only when spans exceed 4.9 m (~16 ft)
Σ sjs = sum of joist spans 4.9 = ref. span (m)
Applies only when spans exceed 4.9 m (~16 ft)