Effective 7/1/2026
15A-3-202 Amendments to Chapters 1 through 5 of IRC.
(1)In IRC, Section R101.2, after the sentence ending with “not more than three stories above grade plane in height.” the following words are added:
          “This code shall not require modifications to a building component that is not being altered as part of an alteration, movement, replacement or repair of an existing structure.”
(2)In IRC, Section R101.2, Exception, the following words are deleted:
          “where provided with an automatic sprinkler system complying with Section P2904.”
(3)In IRC, Section R101.2, Exception, the following words are added:
          “6. A triplex or fourplex of no more than two levels with 2-hour fire-resistance-rated vertical shared wall assemblies tested in accordance with ASTM E119 or UL263, 1-hour fire-resistance-rated horizontal floor assemblies tested in accordance with ASTM E119 or UL263, and independent egress for each unit.”
(4)In IRC, Section R102, a new Section R102.7.2 is added as follows:
          “R102.7.2 Physical change for bedroom window egress.  A structure whose egress window in an existing bedroom is smaller than required by this code, and that complied with the construction code in effect at the time that the bedroom was finished, is not required to undergo a physical change to conform to this code if the change would compromise the structural integrity of the structure or could not be completed in accordance with other applicable requirements of this code, including setback and window well requirements.”
(5)In IRC Section R105.2, under Building, the following changes are made:
(a)Number 3 is deleted and replaced with the following:
          “3. Retaining walls retaining less than four feet (1219mm) of unbalanced fill, unless supporting a surcharge or requiring design per Section R404.4.”
(b)Number 10 is deleted and replaced with the following:
          “10. Decks that are not more than 30 inches (762mm) above grade at any point and not requiring guardrails, that do not serve exit door required by Section R311.4.”
(6)In IRC, Section R105.2, a new exception is added:
          “11. Grade level, non-connected conex boxes, less than 350 square feet, used for storage only.”
(7)In IRC, Section R108.3, the following sentence is added at the end of the section:
          “The building official shall not request proprietary information.”
(8)In IRC, Section 109.1.5, is deleted and replaced with the following:
          “R109.1.5 Other inspections. In addition to the inspections listed in R109.1.1 through R109.1.4, the building official shall have the authority to inspect the proper installation of insulation. R109.1.5.1 Weather-resistant exterior wall envelope inspections. An inspection shall be made of the weather-resistant exterior wall envelope as required by Section R703.1 and flashings as required by Section R703.4 to prevent water from entering the weather-resistive barrier.R109.1.5.2 Fire-resistance-rated construction inspection. Where fire-resistance-rated construction is required between dwelling units or due to location on property, the building official shall require an inspection of such construction after lathing or gypsum board or gypsum panel products are in place, but before any plaster is applied, or before board or panel joints and fasteners are taped and finished.”
(9)In IRC, Section R202, the following definition is added:
          “ACCESSORY DWELLING UNIT: A habitable living unit created within the existing footprint of a primary owner-occupied single-family dwelling.”
(10)In IRC, Section R202, the definition for “APPROVED” is modified by adding the words “or independent third-party licensed engineer or architect and submitted to the building official” after the word “official.”
(11)In IRC, Section R202, the definition for “APPROVAL AGENCY” is modified by replacing the word “and” with “or.”
(12)In IRC, Section 202, the definition for “APPROVED SOURCE” is modified by adding the words “or licensed engineer or architect” after the word “official.”
(13)In IRC, Section R202, the following definition is added:
          “CERTIFIED BACKFLOW PREVENTER ASSEMBLY TESTER: A person who has shown competence to test Backflow prevention assemblies to the satisfaction of the authority having jurisdiction under Utah Code, Subsection 19-4-104(4).”
(14)In IRC, Section R202, the definition of “CROSS CONNECTION” is deleted and replaced with the following:
          “CROSS CONNECTION.  Any physical connection or potential connection or arrangement between two otherwise separate piping systems, one of which contains potable water and the other either water of unknown or questionable safety or steam, gas, or chemical, whereby there exists the possibility for flow from one system to the other, with the direction of flow depending on the pressure differential between the two systems (see “Backflow, Water Distribution”).”
(15)In IRC, Section 202, the following definition is added:
          “DUAL SOURCE CONNECTION. A pipe that is installed so that either the nonpotable (i.e. secondary) irrigation water or the potable water is connected to a pressurized irrigation system at one time, but not both at the same time; or a pipe that is installed so that either the potable water or private well water is connected to a residence at one time, but not both at the same time. The potable water supply line shall be protected by a reduced pressure backflow preventer.”
(16)In IRC, Section 202, the following definition is added:
          “ENERGY STORAGE SYSTEM (ESS). One or more devices, assembled together, that are capable of storing energy for supplying electrical energy at a future time.”
(17)In IRC, Section 202, in the definition for “GRAY WATER”, a comma is inserted after the word “washers”; the word “and” is deleted; and the following is added to the end:
          “and clear water wastes which have a pH of 6.0 to 9.0; are non-flammable; non-combustible; without objectionable odors; non-highly pigmented; and will not interfere with the operation of the sewer treatment facility.”
(18)In IRC, Section R202, the definition of “POTABLE WATER” is deleted and replaced with the following:
          “POTABLE WATER.  Water free from impurities present in amounts sufficient to cause disease or harmful physiological effects and conforming to the Utah Code, Title 19, Chapter 4, Safe Drinking Water Act, and Title 19, Chapter 5, Water Quality Act, and the regulations of the public health authority having jurisdiction.”
(19)In IRC, Figure R301.2 (3), is deleted and replaced with R301.2 (3) as follows:

“TABLE R301.2 (3)

GROUND SNOW LOADS FOR SELECTED LOCATIONS IN UTAH

City/Town

County

Ground Snow Load (lb/ft2)

Elevation (ft)

Beaver

Beaver

35

5886

Brigham City

Box Elder

42

4423

Castle Dale

Emery

32

5669

Coalville

Summit

57

5581

Duchesne

Duchesne

39

5508

Farmington

Davis

35

4318

Fillmore

Millard

30

5138

Heber City

Wasatch

60

5604

Junction

Piute

27

6030

Kanab

Kane

25

4964

Loa

Wayne

37

7060

Logan

Cache

43

4531

Manila

Daggett

26

6368

Manti

Sanpete

37

5620

Moab

Grand

21

4029

Monticello

San Juan

67

7064

Morgan

Morgan

52

5062

Nephi

Juab

39

5131

Ogden

Weber

37

4334

Panguitch

Garfield

41

6630

Parowan

Iron

32

6007

Price

Carbon

31

5558

Provo

Utah

31

4541

Randolph

Rich

50

6286

Richfield

Sevier

27

5338

St. George

Washington

21

2585

Salt Lake City

Salt Lake

28

4239

Tooele

Tooele

35

5029

Vernal

Uintah

39

5384

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.”

(20)In IRC, Section R301.6, is deleted and replaced with the following:
          “R301.6 Utah Snow Loads.  The snow loads specified in Table R301.2(5b) shall be used for the jurisdictions identified in that table.  Otherwise, 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.”
(21)In IRC, Section R302.2, the following sentence is added at the end of the paragraph:
          “When an access/maintenance agreement or easement is in place, plumbing, mechanical ducting, schedule 40 steel gas pipe, and electric service conductors including feeders, are permitted to penetrate the common wall at grade, above grade, or below grade.”
(22)In IRC, Section R302.3, a new Exemption 3 is added as follows:
          “3. Accessory dwelling units separated by walls or floor assemblies protected by not less than 1/2-inch (12.7 mm) gypsum board or equivalent on each side of the wall or bottom of the floor assembly are exempt from the requirements of this section.”
(23)In IRC, Section R302.5.1, the last sentence is deleted.
(24)In IRC, Section R302.13, is deleted.
(25)In IRC, Section R303.4, the following exception is added:
          “Exception: Dwelling units tested in accordance with Section N1102.4.1.2 (R402.4.1.2) which has an air tightness of 3.0 ACH (50) or greater do not require mechanical ventilation.”
(26)In IRC, Section R310.1, all words in the last sentence after “or to a yard or court”, are deleted, and Exception 3 of this section is deleted.
(27)In IRC, Section R310.7, in the exception, the words “or accessory dwelling units” are added after the words “sleeping rooms”.
(28)IRC, Sections R311.7.5.1 through R311.7.5.3, are deleted and replaced with the following:
          “R311.7.5.1 Riser height.  The maximum riser height shall be eight inches (203 mm).  The riser shall be measured vertically between leading edges of the adjacent treads.  The greatest riser height within any flight of stairs shall not exceed the smallest by more than 3/8 inch (9.5 mm).
          R311.7.5.2 Tread depth.  The minimum tread depth shall be nine inches (228 mm).  The tread depth shall be measured horizontally between the vertical planes of the foremost projection of adjacent treads and at a right angle to the tread’s leading edge.  The greatest tread depth within any flight of stairs shall not exceed the smallest by more than 3/8 inch (9.5 mm).  Winder treads shall have a minimum tread depth of 10 inches (254 mm) measured as above at a point 12 inches (305 mm) from the side where the treads are narrower.  Winder treads shall have a minimum tread depth of six inches (152 mm) at any point.  Within any flight of stairs, the greatest winder tread depth at the 12-inch (305 mm) walk line shall not exceed the smallest by more than 3/8 inch (9.5 mm).
          R311.7.5.3 Nosing.  The radius of curvature at the leading edge of the tread shall be no greater than 9/16 inch (14.3 mm).  A nosing not less than 3/4 inch (19 mm) but not more than 1 1/4 inches (32 mm) shall be provided on stairways with solid risers.  The greatest nosing projection shall not exceed the smallest nosing projection by more than 3/8 inch (9.5 mm) between two stories, including the nosing at the level of floors and landings.  Beveling of nosing shall not exceed 1/2 inch (12.7 mm).  Risers shall be vertical or sloped from the underside of the leading edge of the tread above at an angle not more than 30 degrees (0.51 rad) from the vertical.  Open risers are permitted, provided that the opening between treads does not permit the passage of a 4-inch diameter (102 mm) sphere.
          Exceptions.
          1.  A nosing is not required where the tread depth is a minimum of 10 inches (254 mm).
          2.  The opening between adjacent treads is not limited on stairs with a total rise of 30 inches (762 mm) or less.”
(29)In IRC, Section R312.2, is deleted.
(30)In IRC, Sections R313.1 through R313.2.1, are deleted and replaced with the following:
          “R313.1 Design and installation.  When installed, automatic residential fire sprinkler systems for townhouses or one- and two-family dwellings shall be designed and installed in accordance with Section P2904 or NFPA 13D.”
(31)In IRC, Section R314.2.2, the words “accessory dwelling units,” are added after the words “Where alterations, repairs.”
(32)In IRC, Section R315.2.2, the words “accessory dwelling units,” are added after the words “Where alterations, repairs.”
(33)In IRC, Section 315.3, the following words are added to the first sentence after the word “installed”: “on each level of the dwelling unit and.”
(34)A new IRC, Section R328.12, is added as follows:
          “R328.12 Signage. A sign located on the exterior of the dwelling shall be installed at a location approved by the authority having jurisdiction which identifies the battery chemistry included in the ESS. This sign shall be of sufficient durability to withstand the environment involved and shall not be handwritten.”
(35)In IRC, Section 403.1.3.5.3, an exception is added as follows:
          “Exception: Vertical steel in footings shall be permitted to be located while concrete is still plastic and before it has set. Where vertical steel resists placement or the consolidation of concrete around steel is impeded, the concrete shall be vibrated to ensure full contact between the vertical steel and concrete.”
(36)In IRC, Section R403.1.6, a new Exception 3 is added as follows:
          “3. When anchor bolt spacing does not exceed 32 inches (813 mm) apart, anchor bolts may be placed with a minimum of two bolts per plate section located not less than four inches (102 mm) from each end of each plate section at interior bearing walls, interior braced wall lines, and at all exterior walls.”
(37)In IRC, Section R403.1.6.1, a new exception is added at the end of Item 2 and Item 3 as follows:
          “Exception: When anchor bolt spacing does not exceed 32 inches (816 mm) apart, anchor bolts may be placed with a minimum of two bolts per plate section located not less than four inches (102 mm) from each end of each plate section at interior bearing walls, interior braced wall lines, and at all exterior walls.”
(38)In IRC, Section R404.1, a new exception is added as follows:
          “Exception: As an alternative to complying with Sections R404.1 through R404.1.5.3, concrete and masonry foundation walls may be designed in accordance with IBC Sections 1807.1.5 and 1807.1.6 as amended in Section 1807.1.6.4 and Table 1807.1.6.4 under these rules.”
(39)In IRC, Section R405.1, a second exception is added as follows:
          “Exception: When a geotechnical report has been provided for the property, a drainage system is not required unless the drainage system is required as a condition of the geotechnical report. The geotechnical report shall make a recommendation regarding a drainage system.”
(40)In IRC, Section R506.2.3, the words “10-mil (0.010 inch; 0.25 mm)” are deleted and replaced with “6-mil (0.006 inch; 0.152 mm)” and the words “conforming to ASTM E1745 Class A requirements” are deleted.
(41)In IRC, Section 507.2.1, Wood materials. The following is added after the words, “in accordance with section R317,” “field applied weather resistant barrier applied to the top of untreated material,”.

Amended by Chapter 47, 2026 General Session