Current through Register Vol. 35, No. 16, August 27, 2024
Section 14.7.4.12 - RAMMED EARTH CONSTRUCTIONA.General. The following provisions shall apply. (1) Rammed earth shall not be used in any building more than two stories in height. The height of every wall of rammed earth without lateral support is specified in Table 1 of 14.7.4.8 NMAC. The height of the wall is defined as the distance from the top of the slab or top of stem wall to the underside of the bond beam.(2) Exterior rammed earth walls shall be a minimum of 18 inches in thickness. Exception: Exterior walls that are also designed as solar mass walls (trombe) as defined by the passive solar heating worksheet, dated June 2004 and prepared by the state of New Mexico energy, minerals and natural resources department, are allowed and shall be minimum thickness of 10 inches, not to exceed two inches. They shall be fully attached to or integrated with any adjacent structural wall and topped with a bond beam that fully attaches them to the bond beam of any adjacent structural wall as described in 14.7.4.17 NMAC.(3) Interior rammed earth walls shall be a minimum of two inches in thickness.(4) The first lift of rammed earth walls shall be of stabilized rammed earth or minimum 2500 psi concrete, rising not less than three and one half inches above finish floor level. Unstabilized rammed earth walls must be covered to prevent infiltration of moisture from the top of the wall at the end of each workday and prior to wet weather conditions, whether the walls are contained within forms or not.(5) Fully stabilized rammed earth walls may be left unprotected from the elements.(6) In no case shall a rammed earth wall be reduced in thickness with back to back channels or nailers. Channels or nailers rammed on both sides of a running wall shall not be opposite each other to avoid an hourglass configuration in the wall section. Channels or nailers on both sides of a running wall shall be separated from each other vertically at a distance no less than the rammed earth wall thickness. (Refer to Figure 4 of the earthen building figures supplement).(7) An architect or engineer registered in the state of New Mexico shall design and seal structural portions of two-story residential rammed earth construction documents.(8) The general construction of the building shall comply with all provisions of the 2001 New Mexico Residential Building Code (NMRBC), unless otherwise provided for in this rule.(9) Passive solar structures incorporating the use of solar mass walls (trombe), direct gain arrays or sunspaces (greenhouses) as defined by the passive solar heating worksheet, dated June 2004 and prepared by the state of New Mexico energy, minerals and natural resources department, are allowed.B.Fireplaces. Adobe or masonry fireplaces and chimneys in rammed earth structures shall comply with 14.7.3.18 NMAC. They shall be integrated into adjacent rammed earth walls during construction or secured to them by suitable steel ladder reinforcement or reinforcing rods.C.Count Rumford fireplaces. Count Rumford fireplaces are allowed as provided in 14.7.3.18 NMAC.D.Stop work. The building inspector shall have the authority to issue a "stop work" order if the provisions of this section are not complied with.E.Lateral support. Lateral support shall occur at intervals not to exceed 24 feet. Rammed earth walls 18 inches to less than 24 inches thick shall be laterally supported with any one or combination of the following: a rammed earth wall of bond beam height that intersects the running wall with at least 60 degrees of support (refer to a Figure 5 of the earthen building figures supplement); an adobe wall of bond beam height and at least 10 inches in width that intersects with and attaches to the running wall with at least 60 degrees of support (refer to Figure 5 of the earthen building figures supplement); a minimum 20 gauge steel frame or wood frame wall of full height that intersects with and attaches to the running wall with 90 degrees of support, that is properly cross-braced or sheathed (refer to Figure 6 of the earthen building figures supplement); a buttress configuration that intersects the running wall at 90 degrees, of adobe or rammed earth. The buttress base must project a minimum of three feet (or thirty-three percent of the wall height) from the running wall and support at least seventy-five percent of the total wall height (refer to Figure 7 of the earthen building figures supplement). The thickness of a rammed earth buttress shall be at least 18 inches. The thickness of an adobe buttress shall be a minimum 14 inches. Rammed earth walls greater than 24 inches in thickness are self-buttressing and do not require lateral support provided their design adheres to Table 1 of 14.7.4.8 NMAC and the other applicable provisions of this rule.F.Openings. Door and window openings shall be designed such that the opening shall not be any closer to an outside corner of the structure as follows. (1) In rammed earth walls 18 inches to less than 24 inches thick, openings shall not be located within three feet of any corner of the structure. (Refer to Figure 8 of the earthen building figures supplement). Exception: Openings may be located within three feet of any corner provided a buttress extending at least three feet from the structure supports the corner. A continuous footing below and a continuous bond beam above shall be provided across such openings.(2) Rammed earth walls greater than 24 inches thick are self-buttressing, with no special consideration for placement of openings within the area of the wall.G.Piers. Rammed earth piers supporting openings shall measure no less than three square feet in area and no dimension shall be less than 18 inches. (Refer to Figures 9-A and 9-B of the earthen building figures supplement).14.7.4.12 NMAC - Rp, 14.7.4.12 NMAC, 1-28-11; A, 9-1-13, Adopted by New Mexico Register, Volume XXVII, Issue 21, November 15, 2016, eff. 11/15/2016, Amended by New Mexico Register, Volume XXXIV, Issue 11, June 13, 2023, eff. 7/14/2023