§ 4-7 RESIDENTIAL FOUNDATIONS AND FOOTINGS.
   All exterior walls shall have footings of the following minimum standards:
   (A)   Minimum depth of concrete footings on veneer exterior 18 inches and 16 inches wide.
   (B)   Minimum depth on concrete footings on frame exterior walls 12 inches by 16 inches wide.
   (C)   All footings shall be 2,500 psi, minimum compressive strength concrete and reinforced with two No. 4 bars, one at top and one at bottom. The bottom bar shall be at least four inches off bottom of dug footing.
   (D)   All footing shall be poured in a minimum of six inches into undisturbed soil. Ten-inch diameter beams shall be eight feet on center eight inches into undisturbed soil acceptable.
   (E)   Where pier and grade beam type of foundation is proposed for residential construction, design of grade beam and piers shall be:
      (1)   Piers.
         (a)   Minimum diameter: ten inches.
         (b)   Minimum depth: 30 inches, extending eight inches into undisturbed soil.
      (2)   Grade beam width.
         (a)   Six inches for frame construction.
         (b)   Eight inches for masonry brick or rock veneer.
      (3)   Minimum effective depth.
         (a)   Eight inches for slab construction.
         (b)   Sixteen-inch supports for wood floors providing this clearance under joists.
         (c)   Reinforced with two No. 4 bars spaced equally one at top and one at bottom for frame construction.
         (d)   For masonry, veneer, brick, rock and the like, construction reinforced with four No. 4 bars, spaced equally, two at top and two at bottom.
      (4)   Commercial foundations.
         (a)   The design of foundations for masonry construction other than residential shall be prepared and certified by a professional engineer registered in the state and approved by the city.
         (b)   Metal structures as per manufacturers design.
      (5)   Concrete slab floors. All concrete slab floors shall meet the following minimum standards:
         (a)   All concrete slabs on grade shall be nominal four inches thick on four-inch sand base.
         (b)   All concrete shall be minimum 3,000 psi compressive strength.
         (c)   All concrete floors shall be a minimum of eight inches above finished grade.
(`90 Code, § 4-6.1) (Ord. 2786, passed 11-5-85)