§ 15A-3-203 — Amendments to Chapters 6 through 15 of IRC.

Utah § 15A-3-203

• Jurisdiction: Utah
• Title 15A: State Construction and Fire Codes Act
• Ch. 15A-3: Statewide Amendments Incorporated as Part of State Construction Code
• Part 15A-3-2: Statewide Amendments to International Residential Code

Text

(1) IRC, Section R609.4.1, is deleted.
(2) In IRC, Section N1101.4 (R102.1.1), a new section N1101.4.1 (R102.1.1) is added as follows: "N1101.4.1 National Green Building Standard. Buildings complying with ICC 700-2020 National Green Building Standard and achieving the Gold rating level for the energy efficiency category shall be deemed to exceed the energy efficiency required by this code. The building shall also meet the requirements identified in table N1105.2 and the building thermal envelope efficiency is greater than or equal to levels of efficiency and solar heat gain coefficients (SHGC) in Tables N1102.2.2 and N1102.1.3 of the 2009 IRC."
(3) In IRC, Section N1101.5 (R103.2), all words after the words "herein governed." are deleted and replaced with the following: "Construction documents include all documentation required for building permits shall include only those items specified in Subsection 10-20-909(12) or 17-79-810(12) of the Utah Code."
(4) In IRC, Section N1101.10.3 (R303.1.3) the following changes are made:
(4)(a) The following is added at the end of the first sentence "or EN 14351-1:2006+A1:2010."
(4)(b) The word "accredited" is replaced with "approved" in the third sentence.
(4)(c) The following sentence is added after the third sentence: "A conversion factor of 5.678 shall be used to convert from U values expressed in SI units: ()/53678=."
(4)(d) After "NFRC 200" the following words are added: "or EN 14351-1:2006+A1:2010," and in the sentence the word "accredited" is replaced with the word "approved."
(4)(e) The following new sentence shall be inserted immediately before the last sentence: "Total Energy Transmittance values may be substituted for SHGC, and Luminous Transmission values may be substituted for VT."
(5) In IRC, Section N1101.12 (R303.3), all wording after the first sentence is deleted.
(6) In IRC, Section N1101.13 (R401.2), in the first sentence, the words "Section N1101.13.5 and" are deleted.
(7) In IRC, Section N1101.13.5 (R401.2.5) is deleted.
(8) In IRC, Section N1101.14 (R401.3) Number 7, the words "and the compliance path used" are deleted.
(9) In IRC, Table N1102.1.2 (R402.1.2):
(9)(a) in the column titled Fenestration U-Factor the following changes are made:
(9)(a)(i) in the row titled "Climate Zone 3" delete 0.30 and replace it with 0.32;
(9)(a)(ii) in the row titled "Climate Zone 5 and Marine 4" delete 0.30 and replace it with 0.32; and
(9)(a)(iii) in the row titled "Climate Zone 6" delete 0.30 and replace it with 0.32;
(9)(b) in the column titled "Glazed Fenestration SHGC", the following change is made: in the row titled "Climate Zone 3" delete 0.25 and replace it with 0.35;
(9)(c) in the column titled "Ceiling U-Factor" the following changes are made:
(9)(c)(i) in the row titled "Climate Zone 3" delete 0.026 and replace it with 0.030;
(9)(c)(ii) in the row titled "Climate Zone 5 and Marine 4" delete 0.024 and replace it with 0.026; and
(9)(c)(iii) in the row titled "Climate Zone 6" delete 0.024 and replace it with 0.026;
(9)(d) in the column titled "Wood Frame Wall U Factor", the following changes are made:
(9)(d)(i) in the row titled "Climate Zone 3" delete 0.060 and replace it with 0.060;
(9)(d)(ii) in the row titled "Climate Zone 5 and Marine 4" delete 0.045 and replace it with 0.060; and
(9)(d)(iii) in the row titled "Climate Zone 6" delete 0.045 and replace it with 0.060;
(9)(e) in the column titled "Basement Wall U-Factor" the following changes are made:
(9)(e)(i) in the row titled "Climate Zone 5 and Marine 4" delete 0.050 and replace it with 0.075; and
(9)(e)(ii) in the row titled "Climate Zone 6" delete 0.50 and replace it with 0.065; and
(9)(f) in the column titled "Crawl Space Wall U-Factor" the following changes are made:
(9)(f)(i) in the row titled "Climate Zone 5 and Marine 4" delete 0.055 and replace it with 0.078; and
(9)(f)(ii) in the row titled "Climate Zone 6" delete 0.55 and replace it with 0.065.
(10) In IRC, Table N1102.1.3 (R402.1.3), the following changes are made:
(10)(a) in the column titled "Wood Frame Walls R-Value" a new footnote indicator "j" is added and at the bottom of the footnotes the following footnote "j" is added: "j. In climate zone 3B and 5B, an R-15, and in climate zone 6, an R-20 shall be acceptable where air-impermeable insulation is installed in the cavity space, exterior continuous insulation, or some combination thereof; and the tested house air leakage is a maximum of 2.0 ACH50"; and
(10)(b) add a new footnote "k" as follows: "k. Log walls complying with ICC400 and with a minimum average wall thickness of 5 inches or greater shall be permitted in Zones 5 through 8 when overall window glazing has 0.30 U-factor or lower, minimum heating equipment efficiency is for gas 95 AFUE, or for oil, 84 AFUE, and all other components requirements are met."
(11) In IRC, Table N1102.1.3 (R402.1.3) the following changes are made:
(11)(a) in the column titled "Fenestration U-Factor" the following changes are made:
(11)(a)(i) in the row titled "Climate Zone 3" delete 0.30 and replace it with 0.32;
(11)(a)(ii) in the row titled "Climate Zone 5 and Marine 4" delete 0.30 and replace it with 0.32; and
(11)(a)(iii) in the row titled "Climate Zone 6" delete 0.30 and replace it with 0.32;
(11)(b) in the column titled "Glazed Fenestration SHGC" the following change is made: in the row titled "Climate Zone 3" delete 0.25 and replace it with 0.35;
(11)(c) in the Column R-Value the following changes are made:
(11)(c)(i) in the row titled "Climate Zone 3" delete 49 and replace it with 38;
(11)(c)(ii) in the row titled "Climate Zone 5 and Marine 4" delete 60 and replace it with 49; and
(11)(c)(iii) in the row titled "Climate Zone 6" delete 60 and replace it with 49;
(11)(d) in the Column titled "Wood Frame Wall R-Value" the following changes are made:
(11)(d)(i) in the row titled "Climate Zone 3" delete all values and replace with 20+Oci or 13+5ci or 015ci;
(11)(d)(ii) in the row titled "Climate Zone 5 or Marine 4" delete all values and replace with 21+Oci or 15+5ci or 0+15ci; and
(11)(d)(iii) in the row titled "Climate Zone 6" delete all values and replace with 21+Oci or 15+5ci or 0+15ci;
(11)(e) in the column titled "Basement Wall R Value" the following changes are made:
(11)(e)(i) in the row titled "Climate Zone 5 or Marine 4" delete all values and replace with 15+Oci or 0+11ci or 11+5ci; and
(11)(e)(ii) in the row titled "Climate Zone 6" delete all values and replace with 19+Oci or 0+13ci or 11+5ci;
(11)(f) in the column titled "Slab R Value and Depth" the following changes are made:
(11)(f)(i) in the row titled "Climate Zone 3" delete 10ci. 2 ft and replace it with NR; and
(11)(f)(ii) in the row titled "Climate Zone 5 & Marine 4" delete 4 ft and replace it with 2 ft; and
(11)(g) in the column titled "Crawl Space Wall R-Value" the following changes are made:
(11)(g)(i) in the row titled "Climate Zone 5 or Marine 4" delete all values and replace with 15+Oci or 0+11ci or 11+5ci; and
(11)(g)(ii) in the row titled "Climate Zone 6" delete all values and replace with 19+Oci or 0+13ci or 0+11+5ci.
(12) In IRC, a new subsection N1102.1.5.1 (R402.1.5.1) is added as follows: "1102.1.5.1 (R402.1.5.1) RESCheck 2012 Utah Energy Conservation Code. Compliance with section N1102.1.5 (R402.1.5) may be satisfied using the software RESCheck 2012 Utah Energy Conservation Code, which shall satisfy the R-value and U-factor requirements of N1102.1, N1102.2, and N1102.3, provided the following conditions are met:
(12)(a) in "Climate Zone 5 and 6" the software result shall show 5% better than code; and
(12)(b) in "Climate Zone 3", the software result shall show 5% better than code when software inputs for window U-factor .65 and window SHGC=0.40, notwithstanding actual windows installed shall conform to requirements of Tables N1102.1.2 (R402.1.2) and N1102.1.3 (R402.1.3)."
(13) In IRC, Sections N1102.2.1 (R402.2.1), a new Section N1102.2.1.1 is added as follows: "N1102.2.1.1. Unvented attic and unvented enclosed rafter assemblies. Unvented attic and unvented enclosed rafter assemblies conforming to Section R806.5 shall be provided with an R-value of R-22 (maximum U-Factor of 0.045) in Climate Zone 3-B or an R-value of R-26 (maximum U-factor of 0.038) in Climate Zones 5-B and 6-B shall be permitted provided all the following conditions are met: 1. The unvented attic assembly complies with the requirements of the International Residential Code, R806.5. 2. The house shall attain a blower door test result 2.5ACH 50. 3. The house shall require a whole house mechanical ventilation system that does not rely solely on a negative pressure strategy (must be positive, balanced or hybrid). 4. Where insulation is installed below the roof deck and the exposed portion of roof rafters are not already covered by the R-20 depth of the air-impermeable insulation, the exposed portion of the roof rafters shall be wrapped (covered) by minimum R-3 unless directly covered by drywall/finished ceiling. Roof rafters are not required to be covered by minimum R-3 if a continuous insulation is installed above the roof deck. 5. Indoor heating, cooling and ventilation equipment (including ductwork) shall be inside the building thermal envelope."
(14) In IRC, Section N1102.2.9.1 (R402.2.9.1) the numeral (i) is added before the words "cut at a 45 degree" and the following is added after the words "exterior wall": "or (ii) lowered from top of slab 4" when a 4" thermal break material such as, but not limited to, felt or asphalt impregnated fiber board, with a minimum thickness of 1/4" is installed at the upper 4" of slab".
(15) In IRC, Section N1102.4.1 (R402.4.1), in the first sentence, the word "and" is deleted and replaced with the word "or."
(16) In IRC, Section N1102.4.1.1 (R402.4.1.1), the last sentence is deleted and replaced with the following: "Where allowed by the code official, the builder may certify compliance to components criteria for items which may not be inspected during regularly scheduled inspections."
(17) In IRC, Table N1102.4.1.1 (R402.4.1.1) in the column titled "COMPONENT, the following changes are made:
(17)(a) In the row "Rim Joists" the word "exterior" in the first sentence is deleted, and the second sentence is deleted.
(17)(b) In the row "Electrical/phone box on the exterior walls" the last sentence is deleted and replaced with: "Alternatively, close cell foam, caulking or gaskets may be used, or air sealed boxes may be installed."
(18) In IRC, Section N1102.4.1.2 (R402.4.1.2), the following changes are made:
(18)(a) In the fourth sentence, the word "third" is deleted.
(18)(b) The following sentence is added after the fourth sentence: "The following parties shall be approved to conduct testing: Parties certified by BPI or RESNET, or licensed contractors who have completed training provided by Blower Door Test equipment manufacturers or other comparable training."
(18)(c) In the first Exception the second sentence is deleted.
(19) IRC, Section N1103.3.3 (R403.3.3), is deleted.
(20) IRC Section N1103.3.3.1 (R403.3.3.1) is deleted.
(21) In IRC, Section N1103.3.5 (R403.3.5), the following changes are made:
(21)(a) a second Exception is added as follows: "A duct leakage test shall not be required for any system designed such that no air handlers or ducts are located within unconditioned attics."; and
(21)(b) the following is added at the end of the section: "The following parties shall be approved to conduct testing:
(21)(b)(i) Parties certified by BPT or RESNET; and
(21)(b)(ii) Licensed contractors who have completed training provided by Duct Test equipment manufacturers or other comparable training."
(22) In IRC, Section N1103.3.6 (R403.3.6) the following changes are made:
(22)(a) in Subsection 1:
(22)(a)(i) the number 4.0 is changed to 6.0;
(22)(a)(ii) the number 113.3 is changed to 170;
(22)(a)(iii) the number 3.0 is changed to 5.0; and
(22)(a)(iv) the number 85 is changed to 141;
(22)(b) in Subsection 2:
(22)(b)(i) the number 4.0 is changed to 5.0; and
(22)(b)(ii) the number 113.3 is changed to 141; and
(22)(c) Subsection 3 is deleted.
(23) In IRC, Section N1103.3.7 (R403.3.7) the words "or plenums" are deleted.
(24) In IRC, Section N1103.5.1.1 (R403.5.1.1) the words "Where installed" are added at the beginning of the first sentence.
(25) In IRC, Section N1103.5.2 (R403.5.2) the following change is made, Subsections 5 and 6 are deleted and Subsection 7 is renumbered to 5.
(26) IRC, Section N1103.6.2 (R403.6.2), is deleted and replaced with the following: "N1103.6.2 (R403.6.2) Whole-house mechanical ventilation system fan efficacy. Fans used to provide whole-house mechanical ventilation shall meet the efficacy requirements of Table N1103.6.2 (R403.6.2). Exception: Where an air handler that is integral to tested and listed HVAC equipment is used to provide whole-house mechanical ventilation, the air handler shall be powered by an electronically commutated motor."
(27) In IRC, Section N1103.6.2 (R403.6.2), the table is deleted and replaced with the following: "TABLE N1103.6.2 (R403.6.2)", MECHANICAL VENTILATION SYSTEM FAN EFFICACYFAN LOCATIONAIR FLOW RATE MINIMUM (CFM)MINIMUM EFFICACY (CFM/WATT)AIR FLOW RATE MAXIMUM (CFM)HRV or ERVAny1.2 cfm/wattAnyRange hoodsAny2.8 cfm/wattAnyIn-line fanAny2.8 cfm/wattAnyBathroom, utility room101.4 cfm/watt90Bathroom, utility room902.8 cfm/wattAny"
(28) IRC, Section N1103.6.3 (R403.6.3) is deleted.
(29) In IRC, Section N1103.7 (R403.7) the word "approved" is deleted in the first sentence and the following is added after the word "methodologies": "complying with N1103.7.1 (R403.7.1)".
(30) A new IRC, Section N1103.7.1 (R403.7.1) is added as follows: "N1103.7.1 Qualifications. An individual performing load calculations shall be qualified by completing HVAC training from one of the following: 1. HVAC load calculation education from ACCA; 2. A recognized educational institution; 3. HVAC equipment manufacturer's training; or 4. Other recognized industry certification."
(31) In IRC, Section N1104.1 (R404.1), the word "All" is replaced with "Not less than 90 percent of the lamps in".
(32) IRC, Section N1104.1.1 (R404.1.1) is deleted.
(33) IRC, Section N1104.2 (R404.2) is deleted.
(34) IRC, Section N1104.3 (R404.3) is deleted.
(35) In IRC, section N1105.2 (R405.2) the following changes are made:
(35)(a) In Subsection 3, the words "approved by the code official" are deleted; and
(35)(b) In Subsection 3, the following words are added at the end of the sentence: "when applicable and readily available".
(36) In IRC, Section N1106.3 (R406.3) "Building thermal envelope" is deleted, and replaced with "Building thermal envelope and on-site renewables. The proposed total building thermal envelope UA, which is the sum of U-factor times assembly area, shall be less than or equal to the building thermal envelope UA using the prescriptive U-factors from Table N1102.1.2 multiplied by 1.15 in accordance with Equation 11-4. The area-weighted maximum fenestration SHGC permitted in Climate Zones 0 through 3 shall be: 0.30.UAProposed design =1.15xUAPrescriptive reference design (Equation 11-4)."
(37) In IRC, Section N1106.3.1 (R406.3.1) is deleted.
(38) In IRC, Section N1106.3.2 (R403.3.2) is deleted.
(39) In IRC, Section N1106.4 (R406.4) the following changes are made:
(39)(a) In the first sentence, the words "in accordance with Equation 11-5" are deleted and replaced with: "permitted to be calculated using the minimum total air exchange rate for the rated home (Qtot) and for the index adjustment factor in accordance with Equation 11.5.";
(39)(b) In equation 11-5, the words "Ventilation rate, CFM" are deleted and replaced with: "Qtot"; and
(39)(c) In the last sentence the number "5" is deleted and replaced with "15".
(40) In IRC N1106.5, in the column titled "ENERGY RATING INDEX" of Table R406.5, the following changes are made:
(40)(a) In the row for "Climate Zone 3", "51" is deleted and replaced with "65";
(40)(b) In the row for "Climate Zone 5", "55" is deleted and replaced with "69"; and
(40)(c) In the row for "Climate Zone 6", "54" is deleted and replaced with "68".
(41) In IRC, Section N1108 (R408) is deleted.
(42) In IRC, Section M1401.3 the word "approved" is deleted in the first sentence and the following is added after the word methodologies ", complying with M1401.3.1".
(43) A new IRC, Section M1401.3.1, is added as follows: "M1401.3.1 Qualifications. An individual performing load calculations shall be qualified by completing HVAC training from one of the following: 1. HVAC load calculation education from ACCA; 2. A recognized educational institution; 3. HVAC equipment manufacturer's training; or 4. Other recognized industry certification."
(44) In IRC, Section M1402.1, the following is added at the end of the second sentence: "or UL/CSA 60335-2-40."
(45) In IRC, Section M1403.1, the characters "/ANCE" are deleted.
(46) IRC, Section M1411.9, is deleted.
(47) In IRC, Section M1412.1, the characters "/ANCE" are deleted.
(48) In IRC, Section M1413.1, the characters "/ANCE" are deleted.

Legislative History

Amended by Chapter 15, 2025 Special Session 1