8-13   IRC - Amendment To Sections R403 And R404, And Tables R404.1.1(1) And R404.1(2)
Sections R403 Footings and R404 Foundation Walls of the International Residential Code are hereby amended by adding the following to read as follows:
Minimum Footing and Foundation Requirements for Residential Construction
(1)   The minimum footing foundation requirement, balanced fill, for a one-story residence shall be six (6) inches in width by thirty-six (36) inches below grade, with two #4 horizontal rebar continuous.
(2)   The minimum footing foundation requirement, unbalanced fill, for a one- or two-story frame residence shall be sixteen (16) inches in width by eight (8) inches deep, with two #4 rebar continuous and a minimum eight (8) inch wall of block or concrete.
(3)   In addition to the requirements set forth in subparagraphs (1) and (2) above, the following reinforcement requirements for wall foundation must be met:
8" solid concrete from 60" up to 84" unbalanced fill – three #4 horizontal strands, equally spaced throughout height of wall;
8" block - from 48" to 60" unbalanced fill - one #4 rebar vertical, 4' on center to grade height;
8" block - from 60" to 84" unbalanced fill - one #4 rebar vertical, 4' on center to top of foundation.
Add the following to Section R403.1.4.1 Exceptions:
Detached accessory buildings one-story wood or metal framed buildings not used for human occupancy and separated from the principle building by minimum 15’-0” may comply to the following
(1)   not exceeding 200 square feet in floor area, may be placed upon a concrete slab of four inch minimum thickness.
(2)   not exceeding 625 feet in floor area may use a six-inch wide by eighteen inch deep foundation system with at least twelve inches below grade.
R403.1.6 Foundation Anchorage.
Maximum anchor-bolt spacing shall be 6 feet on center, there shall be a minimum of two bolts per plate section with one bolt located not more than 12 inches from each end of the plate section. Bolts shall be at least 1/2 inch in diameter and shall extend a minimum of 7 inches into masonry or concrete.
(Amended by Ordinance No. 8955, effective 03-31-2005) (Amended by Ordinance No. 9162, effective 05-01-2008) (Amended by Ordinance No. 9365, effective 03-30-2012)
HISTORY
Amended by Ord. 9958 on 12/20/2023