Empirical Foundation Requirements Allowed
Utah State Amendment to Section 1807 of the 2018 International Building Code.

1807.1.6.4 Empirical Concrete Foundation Design. Group R, Division 3 Occupancies three stories or less in height, and Group U Occupancies, which are constructed in accordance with Section 2308, or with other methods employing repetitive wood-frame construction or repetitive cold-formed steel structural member construction, shall be permitted to have concrete foundations constructed in accordance with Table 1807.1.6.4.

TABLE 1807.1.6.4
EMPIRICAL FOUNDATION WALLS (1, 7, 8)
Max
Height		 Top Edge
Support		 Min
Thickness		 Vertical
Steel (2)		 Horizontal
Steel (3)		 Steel at
Openings (4)		 Max Lintel
Length		 Min Lintel
Depth
2’
(610 mm)		 None 6” (5) 2-#4 Bars 2- #4 Bars above;
1- #4 Bar each side
1- #4 Bar below		 2’
(610 mm)		 2” for each foot
of opening
width; min. 6”
3’
(914 mm)		 None 6” #4 @ 32” 3- #4 Bars 2- #4 Bars above;
1- #4 Bar each side
1- #4 Bar below		 2’
(610 mm)		 2” for each foot
of opening
width; min. 6”
4’
(1,219 mm)		 None 6” #4 @ 32” 4- #4 Bars 2- #4 Bars above;
1- #4 Bar each side
1- #4 Bar below		 3’
(914 mm)		 2” for each foot
of opening
width; min. 6”
6’
(1,829 mm)		 Floor or roof
diaphragm
(6)		 8” #4 @ 24” 5- #4 Bars 2- #4 Bars above;
1- #4 Bar each side
1- #4 Bar below		 6’
(1829 mm)		 2” for each foot
of opening
width; min. 6”
8’
(2,438 mm)		 Floor or roof
diaphragm
(6)		 8” #4 @ 24” 6- #4 Bars 2- #4 Bars above;
1- #4 Bar each side
1- #4 Bar below		 6’
(1829 mm)		 2” for each foot
of opening
width; min. 6”
9’
(2,743 mm)		 Floor or roof
diaphragm
(6)		 8” #4 @16” 7- #4 Bars 2- #4 Bars above;
1- #4 Bar each side
1- #4 Bar below		 6’
(1829 mm)		 2” for each foot
of opening
width; min. 6”
Over 9’ (2,743 mm), Engineering required for each column
Dated July 1, 2019
Footnotes:
1.
Based on 3,000 psi (20.6 Mpa) concrete and 60,000 psi (414 Mpa) reinforcing steel.
2.
To be placed in the center of the wall, and extended from the footing to within three inches (76 mm) of the top of the wall; dowels of #4 bars to match vertical steel placement shall be provided in the footing, extending 24 inches (610 mm) into the foundation wall.
3.
One bar shall be located in the top four inches (102 mm), one bar in the bottom four inches (102 mm) and the other bars equally spaced between. Such bar placement satisfies the requirements of Section 1805.9. Corner reinforcing shall be provided so as to lap 24 inches (610 mm).
4.
Bars shall be placed within two inches (51 mm) of the openings and extend 24 inches (610 mm) beyond the edge of the opening; vertical bars may terminate three inches (76 mm) from the top of the concrete.
5.
Dowels of #4 bar at 32 inches on center shall be provided in the footing, extending 18 inches (457 mm) into the foundation wall.
6.
Diaphragm shall conform to the requirements of Section 2308.
7.
Footing shall be a minimum of nine inches thick by 20 inches wide.
8.
Soil backfill shall be soil classification types GW, GP, SW, or SP, per Table 1610.1. Soil shall not be submerged or saturated in groundwater.