1. (a) Site preparation.

   1. (1)

      1. (A) All decayable materials, including grass, leaves, roots, and wood, shall be removed from under the locations of footings and foundations.
      2. (B) Manufactured home purchasers shall provide a site suitable for the placement of a home.
   2. (2) Footings and foundation base blocks shall rest on undisturbed or minimum ninety percent (90%) compacted soil of uniform density and thickness or equivalent base material.

   3. (3)

      1. (A) Soil classification and bearing capacity of the soil must be determined before the foundation is constructed and anchored.
      2. (B) Soil classification and bearing capacity may be determined by one (1) or more of the following methods, unless the soil bearing capacity is established as permitted in subdivision (a)(3)(D) of this section:

2. (i) Soil tests in accordance with generally accepted engineering practices;

   1. (ii) Soil records of the applicable local authority having jurisdiction;

      1. (iii) A pocket penetrometer; or

         1. (iv) If soil classification or bearing capacity cannot be determined by test or soil records, the classification, allowable pressures, and torque value shown in the table below may be used.

            Soil Classification
            Classification Number	ASTM D 2478-00 or D 2488-00	SoilDescription	AllowableSoil BearingPressure PSF	Blow CountASTM D1586-99	Torque ProbeValue(inch-pounds)
            1		Rock or Hard Pan	4,000 +
            2	GW, GP, SW, SP, GM, SM	Sandy Gravel & Gravel; Very Dense and/or Cemented Sands; Coarse Gravel/Cobbles; Preloaded Silts, Clays & Corals	2,000	40 +	More Than 550
            3	GC, SC, ML, CL	Sand; Silty Sand; Clayey Sands; Silty Gravel; Medium Dense Coarse Sands; Sandy Gravel; and Very Stiff Silt, Sand Clays	1,500	24-39	351-550
            4A	CG. MH2	Loose to Medium Dense Sands; Firm to Stiff Clays & Silts; Alluvial Fills	1,000	18-23	276-350
            4B	CH, MH2	Loose Sands; Firm Clays; Alluvial Fills	1,000	12-17	175-275
            5	OL, OH. PT	Uncompacted Fill; Peat; Organic Clays		0-11	Less Than 175

      2. (C) In lieu of determining soil bearing capacity by use of the methods listed in this section, an allowable pressure of one thousand pounds per square foot (1,000 psf) may be used, unless the site-specific information requires the use of lower values based on soil classification and type.
      3. (D) If the soil appears to be composed of peat, organic clays, or uncompacted fill, a registered geologist, registered professional engineer, or registered architect must determine the soil classification and maximum allowable soil bearing capacity.
      4. (E) The installation shall not contribute to ponding of water under the home.

3. (b) Pier foundations — Footings.

   1. (1)

      1. (A) The foundation specifications contained in this section are not intended to address flood loads or special site conditions.
      2. (B) Consult the LAHJ or a registered engineer if the home is to be located in a flood hazard area or has special site considerations.

   2. (2)

      1. (A) Support foundations for each pier shall be concrete, either site built or precast, having minimum dimensions of sixteen inches by sixteen inches by four inches (16” x 16” x 4”).
      2. (B) Other pier support materials may be used if accepted by the manufacturer and the Arkansas Manufactured Home Commission.

   3. (3)

      1. (A) The surface texture of poured concrete footings at each pier location shall be such that the first pier block placed at these locations shall sit firmly and evenly.
      2. (B) If a firm, level contact between the first pier block and the surface of the footing is not possible because of surface irregularities in the footing, masonry mortar shall be used between the entire bottom surface of the first pier block and the footing to establish a solid interface contact that is level.
   4. (4) Precast concrete footings (solid pad blocks) shall be installed in a level position with the entire bottom surface in contact with the site surface.

   5. (5) Using the soil capacity, as described in subdivision (a)(3) of this section, footings should be sized according to the table below. FOOTER SIZING TABLE Based on Soil Bearing Capacity

      Opening Size	1,000 PSF	1,500 PSF	2,000 PSF	4,000 PSF
      4’ – 8’	400 sq in	256 sq in	256 sq in	256 sq in
      8’ – 16‘	576 sq in	400 sq in	256 sq in	256 sq in
      16’ – 20‘	784 sq in	576 sq in	400 sq in	256 sq in
      20’ – 28’	1,156 sq in	784 sq in	576 sq in	256 sq in
      I-Beam Footers (8’ Max Spacing)	576 sq in	400 sq in	256 sq in	256 sq in

      1. (c) Piers — Support columns.

   6. (1) Piers — General construction.

      1. (A)

         1. (i) All piers shall be installed on footings or foundations and shall be centered under the I-beam.
         2. (ii) (ii) All pier columns shall be centered on the footing or foundation.

      2. (B)

         1. (i) No manufactured home piers shall be located more than eight feet (8’) apart on center.
         2. (ii) The first pier shall be located within two feet (2’) from either end of each I‑beam.

      3. (C)

         1. (i) The installation of foundations and piers shall be constructed in a manner that shall demonstrate acceptable workmanship.
         2. (ii) Each course of all piers shall be laid level and true to the vertical and horizontal line.
      4. (D) Upon completion of the pier support system, the manufactured home shall be reasonably level in the longitudinal and side‑to‑side directions.

   7. (2) Piers — Block requirements.

      1. (A) Piers shall be constructed of eight inches by eight inches by sixteen inches (8” x 8” x 16”) concrete building blocks, open celled, solid, or equivalent, that meet or exceed the specifications per ASTM C90, ground-contact rated.
      2. (B) Open celled blocks shall be installed with the open cells vertical.

   8. (3) Piers — Height rules.

      1. (A) No pier shall be installed that is less than twelve inches (12”) in height.

      2. (B)

         1. (i) Piers of three (3) courses of blocks or less shall be of single block construction.
         2. (ii) All piers of single block construction installed under the main I-beam shall be installed perpendicular to the I-beam.
      3. (C) Piers that consist of more than three (3) courses of blocks shall be of doubled block construction and alternate courses shall be interlocking.
      4. (D) (D) When the total height of a support column, including footing, pier blocks, and wood, exceed fifty-two inches (52”), the interlocking blocks shall be filled with concrete and reinforced with three-eighths inch (3/8”) rebar.
      5. (E) When the footings, piers, and wood exceed eighty inches (80”) in height, the pier construction must be designed by a professional engineer or architect and submitted to the commission for approval prior to installation.

   9. (4) Piers — Cap blocks, top plates, and shims.

      1. (A)

         1. (i) A combination of not more than two (2) solid concrete cap blocks two inches (2”), three inches (3”), or four inches (4”) by eight inches by sixteen inches (8” x 16”) may be installed on top of the uppermost pier block.
         2. (ii) No combination of cap blocks may exceed seven inches (7”) in height.
      2. (B) A two inches by eight inches by sixteen inches (2” x 8” x 16”) (nominal) pressure preservative treated wood plate or plates shall completely cover the top of the uppermost concrete building unit or units of each pier.
      3. (C) Additional pressure preservative treated wooden shims with a minimum width of five and one-half inches (5 1/2”), a minimum length of twelve inches (12”), and a minimum thickness of one-quarter inch (1/4”) and a maximum thickness of one inch (1”) may be used between the wood plate and the I-beam.

      4. (D)

         1. (i) Hardwood wedges with a minimum width of four inches (4”), a minimum length of six inches (6”), and a maximum installed thickness of one inch (1”) may be used if placed directly between the last wooden member of the pier and the point of support.
         2. (ii) Wedges shall be centered and driven tight from both sides of the I-beam or marriage line perimeter joists.

   10. (5) Piers — Marriage line and perimeter blocking.

       1. (A)

          1. (i) The marriage line of multisection manufactured homes shall be supported by piers located no more than eight feet (8’) apart on center and shall have piers located within two feet (2’) of each end of the marriage line.
          2. (ii) In addition to these piers, multisection homes shall have piers located under the jamb studs or ridge beam column posts for openings in the marriage wall of four feet (4’) or greater.

       2. (B) Piers shall also be located on each side of any exterior door, fireplace, bay window, or any other opening of forty-eight inches (48”) or more.

          1. (d) Multisection homes — Marriage line and utility connections.

   11. (1) Multisection homes — Sealing of marriage line.

       1. (A) All weatherproofing material (fir strips, plastic, or vinyl sheeting) shall be removed from floor joints, marriage walls, and end walls.

       2. (B)

          1. (i) Sill sealer strips, expanding foam, or other insulating material shall be installed along the ceiling, floor, and end wall marriage lines to prevent air infiltration.
          2. (ii) Such strips or material, other than foam, shall be secured in place with staples or nails.

       3. (C)

          1. (i) Gaps between floor sections or ridge beams that do not extend the full length of the home may not exceed two inches (2”) in width and must be sealed with plywood, lumber, or other building material.
          2. (ii) End wall marriage lines must be covered with exterior siding material to resist the elements.

   12. (2) Multisection homes — Lag bolting and roof ridge connections.

       1. (A)

          1. (i) Floor sections shall be connected with lag bolts of at least five-sixteenths inch (5/16”) and of sufficient length to penetrate into the opposing floor joist at least three-quarters inch (3/4”).
          2. (ii) Lag bolts shall be installed no more than twenty inches (20”) apart on center, alternating sides.
          3. (iii) Bolting must not dislodge the rim joist.
       2. (B) Holes in bottom board caused by lag bolt installation must be sealed.

       3. (C) The roof ridge shall be covered with ridge cap or exterior roofing material to resist the elements and connected with:

          1. (i) Lag bolts installed no more than twenty inches (20”) apart on center, alternating sides; or
          2. (ii)
4. (a) (a) At least one and one-half inch (1 1/2”) twenty-six gauge (26 Ga.) metal straps or equivalent, secured with staples, nails, or screws.

5. (b) (b) A strap shall be installed at each truss, extending at least six inches (6”) on each side of the ridge.

   1. (3) Multisection homes — Utility and air conditioning cross-over connections.

      1. (A) All utility connections made by the installing retailer or installer shall be protected from weather or other elements.

      2. (B)

         1. (i) Electrical connections shall be made inside a junction box.
         2. (ii) Cross-over wiring shall be covered with access panels or be protected by conduit attached with clamps to junction boxes.
      3. (C) The chassis of each section of the home shall be electrically bonded to one another.

      4. (D)

         1. (i) Air conditioning cross-over ducts shall be attached to each plenum with screws and wire ties and taped to prevent air loss.
         2. (ii) The duct shall be suspended above the ground and fastened in place.
         3. (iii) Ties or straps used to suspend the duct shall not crush or crimp the duct in a manner that substantially reduces airflow.

Codification Notes: "LAHJ" means local authority having jurisdiction.