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(1) In IBC, Table 1604.5, Risk Category III, in the sentence that begins "Group I-2 Condition 1," a new footnote c is added as follows: "c. Type II Assisted Living Facilities that are I-2 Condition 1 occupancy classifications in accordance with Section 308 shall be Risk Category II in this table."
(2) In IBC, Section 1605.2, in the portion of the definition for the value of f2, the words "and 0.2 for other roof configurations" are deleted and replaced with the following: "f2 = 0.20 + .025(A-5) for other configurations where roof snow load exceeds 30 psf; f2 = 0 for roof snow loads of 30 psf (1.44kN/m2) or less. Where A = Elevation above sea level at the location of the structure (ft./1,000)."
(3) In IBC, Sections 1605.3.1 and 1605.3.2, exception 2 in each section is deleted and replaced with the following: "2. Flat roof snow loads of 30 pounds per square foot (1.44 kNm2) or less need not be combined with seismic loads. Where flat roof snow loads exceed 30 pounds per square foot (1.44 kNm2), the snow loads may be reduced in accordance with the following in load combinations including both snow and seismic loads. S as calculated below, shall be combined with seismic loads. S = (0.20 + 0.025(A-5))Pf is greater than or equal to 0.20 Pf. Where: S = Weight of snow to be used in combination with seismic loads A = Elevation above sea level at the location of the structure (ft./1,000) Pf = Design roof snow load, psf. For the purpose of this section, snow load shall be assumed uniform on the roof footprint without including the effects of drift or sliding. The Importance Factor, I, used in calculating Pf may be considered 1.0 for use in the formula for Ws".
(4)IBC, Section 1608.1, is deleted and replaced with the following: "1608.1 General. Except as modified in Sections 1608.1.1, 1608.1.2, and 1608.1.3, design snow loads shall be determined in accordance with Chapter 7 of ASCE 7, but the design roof load shall not be less than that determined by Section 1607. Where the minimum live load, in accordance with Section 1607, is greater than the design roof snow load, pf, the live load shall be used for design, but it may not be reduced to a load lower than the design roof snow load. Drifting need not be considered for roof snow loads, pf, less than 20 psf."
(5) A new IBC, Section 1608.1.1, is added as follows: "1608.1.1 Ice dams and icicles along eaves. Section 7.4.5 of Chapter 7 of ASCE 7 referenced in IBC Section 1608.1 is deleted and replaced with the following: 7.4.5 Ice Dams and Icicles Along Eaves. Where ground snow loads exceed 75 psf, eaves shall be capable of sustaining a uniformly distributed load of 2pf on all overhanging portions. No other loads except dead loads shall be present on the roof when this uniformly distributed load is applied. All building exits under down-slope eaves shall be protected from sliding snow and ice."
(6) A new IBC, Section 1608.1.2, is added as follows: "1608.1.2 Thermal factor. The value for the thermal factor, Ct, used in calculation of pf shall be determined from Table 7.3-2 in ASCE 7. Exception: Except for unheated structures, the value of Ct need not exceed 1.0 when ground snow load, pg, is calculated using Section 1608.2.1."
(7) A new IBC, Section 1608.1.3 is added as follows: "1608.1.3 Drifts on adjacent structures. Section 7.7.2 of ASCE 7 referenced in IBC, Section 1608.1, is deleted and replaced with the following: 7.7.2 Adjacent structures. At lower adjacent structures, the requirements of Section 7.7.1 shall be used to calculate windward and leeward drifts. The resulting drift is permitted to be truncated."
(8) A new IBC, Section 1608.2.1 is added as follows: "1608.2.1 Utah ground snow loads. Section 7.2 of ASCE 7 referenced in IBC, Section 1608.1 is modified as follows:
(a) In paragraph 1, 7.2-8 is deleted and replaced with 7.2-9.
(b) On Figure 7.2-1, remove CS and other ground snow load values in the state of Utah. Add red shaded region for the state of Utah with the following note: See note for Utah.
(c) The following is added to the Note on Figure 7.2.1: See Table 7.2-9 for Utah.
Note: To convert lb/ft2 to kN/m2, multiply by 0.0479. To convert feet to meters, multiply by 0.3048. 1. Statutory requirements of the Authority Having Jurisdiction are not included in this state ground snow load table. 2. For locations where there is substantial change in altitude over the city/town, the load applies at and below the cited elevation, with a tolerance of 100 ft (30 m). 3. For other locations in Utah, see Bean, B., Maguire, M., Sun, Y. (2018), "The Utah Snow Load Study," Utah State University Civil and Environmental Engineering Faculty Publications, Paper 3589, http://utahsnowload.usu.edu/, for ground snow load values.
(9) A new IBC, Section 1613.1.1, is added as follows: "1613.1.1 Effective Seismic Weight. In ASCE 12.7.2 and 12.14.8.1 as referenced in Section 1613.1, Definition of W, Item 4 is deleted and replaced with the following: 4. Where flat roof snow load, Pf, exceeds 30 psf, the snow load included in the effective seismic weight shall be calculated, in accordance with the following equation: Ws = (0.20 + 0.025(A-5))Pf >= 0.20 Pf. WHERE: Ws = Weight of snow to be included as effective seismic weight A = Elevation above sea level at the location of the structure (ft./1,000) Pf = Design roof snow load, psf. For the purposes of this section, snow load shall be assumed uniform on the roof footprint without including the effects of drift or sliding. The Importance Factor, I, used in calculating Pf may be considered 1.0 for use in the formula for Ws."