New Mexico Administrative Code
Title 14 - HOUSING AND CONSTRUCTION
Chapter 7 - BUILDING CODES GENERAL
Part 4 - 2021 NEW MEXICO EARTHEN BUILDING MATERIALS CODE
Section 14.7.4.13 - FOUNDATIONS
Current through Register Vol. 35, No. 18, September 24, 2024
A. General. Foundation construction shall comply with applicable provisions of the 2009 New Mexico Residential Building Code, and the following: a minimum of three continuous #4 reinforcing rods are required in concrete footings supporting rammed earth walls. Footings shall be a minimum of 10 inches in thickness. Concrete footings and concrete stem walls supporting rammed earth walls shall be a minimum of 2500 psi. Stem walls shall be the full width of the wall supported above or wider to receive forming systems. Stem walls shall rise above exterior grade a minimum of six inches.
B. Perimeter insulation. For the purposes of placement of perimeter insulation, rammed earth walls may overhang the bearing surface up to the thickness of the perimeter insulation, but in no case greater than two inches.
C. Keyway. A key way shall be provided where the rammed earth wall meets the foundation system. The keyway shall be established at the top of the stem a minimum of two inches deep by six inches wide formed at the time of the pour, and shall run continuously around the structure to include any intersecting rammed earth wall sections. The rammed earth wall shall be fully rammed into this keyway (refer to Figure 2 of the earthen building figures supplement). Exception: Placement of vertical reinforcing rods extending a minimum two inches into the rammed earth wall. The vertical rods shall be minimum #4, imbedded into the concrete and spaced 48 inches on center, maximum.
D. Concrete grade beam. Rubble filled foundation trench designs with a reinforced concrete grade beam above are allowed to support rammed earth wall construction. An architect or engineer registered in the state of New Mexico shall certify the grade beam/rubble-filled trench design portion.
