Current through Register Vol. 35, No. 8, April 23, 2024
Section 14.7.3.17 - CHAPTER 9 ROOF ASSEMBLIESSee this chapter of the IRC except as provided below.
A.Section R903 Weather Protection. See this section of the IRC except as provided below. (1)Section R903.2.1 Locations. See this section of the IRC and the following to the end of the section: Approved reglets or an approved flashing shall be installed at wall and roof intersections, wherever there is a change in roof slope or direction and around roof openings. Where flashing is of metal, the metal shall be corrosion resistant with a thickness of not less than 0.019 inch (0.5 mm) (No. 26 galvanized sheet).(2)Section R903.3 Coping. Delete the text of this section and substitute with the following: Plastered parapets shall require a seamless but permeable waterproof cover or weather barrier, capping the entire parapet and wrapping over each side. The cover shall extend past any break from the vertical a minimum of four inches on the wall side. On the roof side, the cover shall properly lap any rising roof felts or membranes and be properly sealed. A layer of furred expanded metal lath shall be installed over the cover before plaster or stucco is applied. The lath shall extend past any break from the vertical on the wall side a minimum of five inches and on the roof side, the same distance as the cover below, allowing for plaster stops or seals. No penetrating fasteners are allowed on the horizontal surface of parapets.B.Section R904 Materials. See this section of the IRC except add the following new section: Section R904.5 Loose granular fill. Pumice and other granular fill type materials are not permitted in roof assemblies.C.Section R905 Requirements for Roof Coverings. See this section of the IRC except add the following new sections.(1)Section R905.9 Built-up roofs. See this section of the IRC except add the following sections: (a)Section R905.9.4 Roof deck transitions. Where roof sheathing is overlapped to create drainage "crickets" or valleys to canales, taper board, or equivalent shall be used to transition between the two deck levels to create a uniform substrate.(b)Section R905.9.5 Canales and scuppers. All canales and scuppers must have a metal pan lining extending six inches minimum past the inside of the parapet and six inches minimum to each side of the canale or scupper opening. All canales or scuppers must have positive drainage.(2)Section R905.11 Modified bitumen roofing. See this section of the IRC except add the following section: Section R905.11.4 Roof deck transitions. Where roof sheathing is overlapped to create drainage "cricket" or valleys to canales, taperboard or equivalent shall be used to transition between the two deck levels to create a uniform substrate.(3)Section R905.12 Thermoset single-ply roofing. See this section of the IRC except add the following section: Section R905.12.4 Roof deck transitions. Where roof sheathing is overlapped to create drainage "crickets" or valleys to canales, taperboard or equivalent shall be used to transition between the two deck levels to create a uniform substrate.(4)Section R905.13 Thermoplastic single-ply roofing. See this section of the IRC except add the following section: Section R905.13.4 Roof deck transitions. Where roof sheathing is overlapped to create drainage "crickets" or valleys to canales, taperboard or equivalent shall be used to transition between the two deck levels to create a uniform substrate.D.Section R908 Reroofing. See this section of the IRC except as provided below. Section R908.3 Roof Replacement. Delete the text of this section and substitute with the following: New roof coverings shall not be installed without first removing existing roof coverings where any of the following conditions occur: (1) The existing roof or roof covering is water soaked or has deteriorated to the point that the existing roof or roof covering is not adequate as a base for additional roofing.(2) The existing roof covering is wood shake, slate, clay, cement, or asbestos-cement tile.(3) The existing roof has two or more applications of any type of roof covering.(4) Where pumice or other granular fill are present, the material must be removed prior to installing a new roof.14.7.3.17 NMAC - Rp, 14.7.3.17 NMAC, 1-28-11; A, 04-01-13; A, 09-01-13, Adopted by New Mexico Register, Volume XXVII, Issue 21, November 15, 2016, eff. 11/15/2016, Adopted by New Mexico Register, Volume XXXIV, Issue 11, June 13, 2023, eff. 7/14/2023