Section R403.1.1, Minimum Size, of the IRC, is hereby amended by adding the following Table R403.1(4):
For purposes of sizing and construction of footings for residential conventionally light-framed construction with cast-in-place or fully grouted masonry foundation wall construction, constructed upon undisturbed, non-expansive soils, the following table and footnotes may be used in lieu of table R403.1(1), R403.1(2), R403.1(3):
Table R403.1(4)
Number Stories | Foundation Wall Thickness | Minimum Footing Thickness (inches) | Minimum Footing Width (inches) | Minimum Continuous Reinforcement (rebar) | |
Concrete | Masonry
| ||||
1 | 8 | 8 | 8 | 16 | 2 - #4 |
2 | 8 | 8 | 8 | 16 | 2 - #4 |
Demising Walls | 8 | 8 | 8 | 18 | 2 - #4 |
3 | 10 | 10 | 12 | 22 | 3 - #4 |
Demising Walls | 10 | 10 | 12 | 22 | 3- #4 |
a. assumed soil bearing capacity 2000 psf
b. foundations placed upon areas of poor bearing or expansive soils shall be engineered
c. footings carrying point loads shall be engineered
d. foundations may support a roof in addition to the stipulated number of floors
e. foundations supporting a roof only shall be as required for supporting one floor
f. reinforcing shall be evenly spaced with proper overlaps
g. perimeter footings shall be minimum 42” below surrounding grade within 5’ horizontally of foundation