STANDARDS

1. (a) The Department adopts and incorporates by reference the following codes as the Uniform Construction Code:

   1. (1) The provisions of Chapters 2—10, 12—29 and 31—35 of the ‘‘International Building Code of 2021,’’ except:

      1. (i) In occupancies in Use Group R-3 and within dwelling units in occupancies in Use Group R-2, the maximum riser height shall be 8 1/4 inches (210 mm) and the minimum tread depth shall be 9 inches (229 mm). A 1-inch (25 mm) nosing shall be provided on stairways with solid risers.

      2. (ii) The following provisions of Chapter 30 are adopted:

         1. (A) Section 3002.1 (relating to hoistway enclosure protection).
         2. (B) Section 3002.2 (relating to number of elevator cars in a hoistway).
         3. (C) Section 3002.4 (relating to elevator car to accommodate ambulance stretcher).
         4. (D) Section 3002.7 (relating to common enclosure with stairway).
         5. (E) Section 3004.2.1 (relating to enclosure).
         6. (F) Section 3004.3.1 (relating to enclosure).
         7. (G) Section 3005.4 (relating to machine rooms, control rooms, machinery spaces, and control spaces).
         8. (H) Section 3006 (relating to elevator lobbies and hoistway opening protection).
         9. (I) Section 3007 (relating to fire service access elevators).
         10. (J) Section 3008 (relating to occupant evacuation elevators).

      3. (iii) The following provisions are modified:

         1. (A) Section 803.3 (relating to heavy timber exemption) is modified to add the phrase: ‘‘In buildings equipped throughout with an automatic sprinkler system installed in accordance with section 903.3,’’ before the word ‘‘exposed.’’

         2. (B) Section 903.3.1.2 (relating to NFPA 13R sprinkler systems) is modified by changing the second condition to read:

            2. For other than R-2 occupancies, the floor level of the highest story is 30 feet (9,144 mm) or less above the lowest level of fire department vehicle access.

            For R-2 occupancies, the roof assembly is less than 45 feet (13,716 mm) above the lowest level of fire department vehicle access. The height of the roof assembly shall be determined by measuring the distance from the lowest required fire vehicle access road surface adjacent to the building to the eave of the highest pitched roof, the intersection of the highest roof to the exterior wall, or the top of the highest parapet, whichever yields the greatest distance.

      4. (iv) The following provisions are excluded:

         1. (A) Section 426.1 (relating to buildings in which materials that produce combustible dusts are stored or handled).
         2. (B) Section 704.2 (relating to column protection).
         3. (C) Section 704.4.1 (relating to light-frame construction).

      5. (v) The following previously adopted provisions of the ‘‘International Building Code of 2015’’ remain in effect:

         1. (A) Section 704.2 (relating to column protection).
         2. (B) Section 704.4.1 (relating to light frame construction).

      6. (vi) The following previously adopted provision of the ‘‘International Building Code of 2018’’ remains in effect:

         1. (A) Section 426.1 (relating to buildings in which materials that produce combustible dusts are stored or handled).
   2. (2) {Reserved}.
   3. (3) The ‘‘International Mechanical Code of 2021.’’
   4. (4) The ‘‘International Fuel Gas Code of 2021.’’
   5. (5) The ‘‘International Performance Code for Buildings and Facilities of 2021.’’

   6. (6) The ‘‘International Plumbing Code of 2021’’ except:

      1. (i) A municipality within a county of the second class may not administer and enforce the ‘‘International Plumbing Code’’ adopted under this chapter.
      2. (ii) A municipality within a county of the second class that has adopted a plumbing code and accompanying rules and regulations under the Local Health Administration Law (16 P.S. § § 12001—12030) shall retain the authority to promulgate and enforce this plumbing code and to make any changes it deems necessary if the changes meet the Uniform Construction Code’s minimum requirements.
      3. (iii) {Reserved}.

   7. (7) The ‘‘International Residential Code of 2021,’’ except that:

      1. (i) The provisions of R314.4 requiring interconnected smoke alarms do not apply to one-family and two-family dwellings undergoing alterations, repairs or additions. Noninterconnected battery-operated smoke alarms shall be installed in these dwellings.

      2. (ii) The following specifications apply to residential stairway treads and risers.

         1. (A) The maximum riser height is 8 1/4 inches. There may be no more than a 3/8 inch variation in riser height within a flight of stairs. The riser height is to be measured vertically between leading edges of the adjacent treads.
         2. (B) The minimum tread depth is 9 inches measured from tread nosing to tread nosing.
         3. (C) The greatest tread depth within any flight of stairs may not exceed the smallest by more than 3/8 inch.
         4. (D) Treads may have a uniform projection of not more than 1 1/2 inches when solid risers are used.
         5. (E) Stairways may not be less than 3 feet in clear width, and clear headroom of 6 feet 8 inches shall be maintained for the entire run of the stair.
         6. (F) Handrails may project from each side of a stairway a distance of 3 1/2 inches into the required width of the stair.

      3. (iii) The following provisions are excluded:

         1. (A) Section R311.7.4 (relating to walkline).
         2. (B) Section R314.4 (relating to interconnection).
         3. (C) Section R325.5 (relating to openness).
         4. (D) Section R703.7 (relating to exterior plaster, stucco).
         5. (E) Section R806.2 (relating to minimum vent required).
         6. (F) Section R1005.8 (relating to insulation shield).
         7. (G) Section N1101.13.5 (relating to additional energy efficiency).
         8. (H) Section N1103.3.5 (relating to duct testing).
         9. (I) Section N1103.3.6 (relating to duct leakage).
         10. (J) Section N1103.3.7 (relating to building cavities).
         11. (K) Section N1104.1 (relating to lighting equipment).
         12. (L) Section N1104.1.1 (relating to exterior lighting).
         13. (M) Section N1104.1.2 (relating to fuel gas lighting equipment).
         14. (N) Section N1104.2 (relating to interior lighting controls).
         15. (O) Section N1104.3 (relating to exterior lighting controls).
         16. (P) Section N1105.3.2 (relating to compliance report).
         17. (Q) Section N1105.3.2.1 (relating to compliance report for permit application).
         18. (R) Table N1105.4.2(1) (relating to specifications for the standard reference and proposed designs).
         19. (S) Section N1106.3 (relating to building thermal envelope).
         20. (T) Section N1106.3.1 (relating to on-site renewables are not included).
         21. (U) Section N1106.3.2 (relating to on-site renewables are included).
         22. (V) Section N1106.4 (relating to energy rating index).
         23. (W) Section N1106.4.1 (relating to ERI referenced design).
         24. (X) Section N1106.7.1 (relating to compliance software tools).
         25. (Y) Section N1106.7.5 (relating to specific approval).
         26. (Z) Section N1106.7.6 (relating to input values).
         27. (AA) Section N1106.8 (relating to calculation software tools).
         28. (BB) Section N1106.8.1 (relating to minimum capabilities).
         29. (CC) Section N1106.8.2 (relating to specific approval).
         30. (DD) Section N1106.8.3 (relating to input values).
         31. (EE) Section M1305.1.3.2 (relating to pit locations).
         32. (FF) Section M1411.6.1 (relating to refrigerant line insulation protection).
         33. (GG) Section M1502.3.1 (relating to exhaust termination outlet and passageway size).
         34. (HH) Section P2903.5 (relating to water hammer).
         35. (II) Section P2905.3 (relating to hot water supply to fixtures).
         36. (JJ) Section P2906.6.1 (relating to saddle tap fittings).
         37. (KK) Section E3901.4.2 (relating to island countertop spaces).
         38. (LL) Section E3901.11 (relating to foyers).
         39. (MM) Section E4002.11 (relating to bathtub and shower space).

      4. (iv) The following provisions are modified:

         1. (A) Section R301.1.4 (relating to intermodal shipping containers) is amended by adding the following language at the end of the section:

            Prior to permitting, the applicant shall have the unit certified as free from contaminants by a qualified 3rd party inspector approved by the AHJ. Any penetrations beyond those permitted in Section 3115 of the International Building Code shall be certified by a Pennsylvania Registered Design Professional.

         2. (B) Section R305.1 (relating to minimum height) is modified by amending exception 4 to read:

            4. Beams and girders spaced apart a minimum of 36 inches (914 mm) in clear finished width between projections, and shall have a minimum clear ceiling height of 6 feet 6 inches (1,981 mm) from the finished floor directly under the beam.

         3. (C) Section R310.1 (relating to emergency escape and rescue opening required) is amended to add the following fourth exemption after exemption 3:

            4. Properties with in-fill lots that are sprinklered in accordance with Section 2904, and a minimum clear yard size of 80 square feet (7.43 m²), shall be allowed to have access to the public way provided by a shared easement that is a minimum of 30 inches (762 mm) wide.

         4. (D) Section R326.3 (relating to story above grade plane) is modified by striking exceptions 3 and 4.
         5. (E) Section R506.2.3 (relating to vapor retarder) is modified by striking ‘‘10 mil (0.010 inch: 0.25 mm) vapor retarder conforming to ASTM E1745 Class A requirements’’ and inserting ‘‘6 mil (0.006 inch: 152 mm).’’

         6. (F) Section R703.2 (relating to water-resistive barrier) is modified to read as follows:

            R703.2 Water-resistive barrier. Not fewer than one layer of water-resistive barrier shall be applied over studs or sheathing of all exterior walls with flashing as indicated in Section R703.4, in such a manner as to provide a continuous water-resistive barrier behind the exterior wall veneer. The water-resistive barrier material shall be continuous to the top of walls and terminated at penetrations and building appendages in a manner to meet the requirements of the exterior wall envelope as described in Section R703.1. Where the water-resistive barrier also functions as a component of a continuous air barrier, the water-resistive barrier shall be installed as an air barrier in accordance with Section N1102.4.1.1. Water-resistive barrier materials shall comply with one of the following:

            1. No. 15 felt complying with ASTM D226, Type 1.

            2. ASTM E2568, Type 1 or 2.

            3. Foam plastic insulating sheathing water-resistive barrier systems complying with Section R703.1.1 and installed in accordance with the manufacturer’s installation instructions.

            4. ASTM E331 in accordance with Section R703.1.1.

            5. Other approved materials in accordance with the manufacturer’s installation instructions.

            No. 15 asphalt felt and water-resistive barriers complying with ASTM E2556 shall be applied horizontally, with the upper layer lapped over the lower layer not less than 2 inches (51 mm), and where joints occur, shall be lapped not less than 6 inches (152 mm).

            Exception: A water-resistive barrier shall not be required in unconditioned detached tool sheds, playhouses, and other similar accessory structures provided all of the following requirements are met:

            1. Exterior wall covering is limited to siding that is attached directly to the studs.

            2. Exterior walls are uninsulated.

            3. Interior side of exterior walls has no wall covering or wall finishes.

         7. (G) Section R703.3.1 (relating to soffit installation) is (1) re-titled ‘‘Exterior soffit installation[;]’’ and (2) the term ‘‘soffits’’ is changed to ‘‘exterior soffits[.]’’

         8. (H) Section R703.4.1 (relating to flashing installation at exterior window and door openings) is modified to read as follows:

            R703.4.1 Flashing installation at exterior window and door openings. Flashing at exterior window and door openings shall extend to the surface of the exterior wall finish or to a water-resistive barrier complying with Section 703.2. for subsequent drainage. Air sealing shall be installed around all window and door openings on the interior side of the rough opening gap. Mechanically attached flexible flashings shall comply with AAMA 712. Flashing at exterior window and door openings shall be installed in accordance with one or more of the following:

            1. The fenestration manufacturer’s installation and flashing instructions, or for applications not addressed in the fenestration manufacturer’s instructions, in accordance with the flashing or water-resistive barrier manufacturer’s instructions. Where flashing instructions or details are not provided, pan flashing shall be installed at the sill of exterior window and door openings. Pan flashing shall be sealed or sloped in such a manner as to direct water to the surface of the exterior wall finish or to the water-resistive barrier for subsequent drainage. Openings using pan flashing shall incorporate flashing or protection at the head and sides.

            2. In accordance with the flashing design or method of a registered design professional.

            3. In accordance with other approved methods.

         9. (I) Section R704.1 (relating to general wind limitations) is modified by changing each of the three ‘‘soffits’’ therein to ‘‘exterior soffits[.]’’
         10. (J) Section R704.2 (relating to soffit installation where the design wind pressure is 30 psf or less) is (1) re-titled ‘‘Exterior soffit installation where the design pressure is 30 psf or less)[;]’’ and (2) the term ‘‘soffit’’ in the first sentence is changed to ‘‘exterior soffit[.]’’ The second sentence is not modified.

         11. (K) Section R704.2.1 (relating to vinyl soffit panels) is modified to read:

             R704.2.1 Vinyl and aluminum soffit panels. Vinyl and aluminum soffit panels shall be installed using aluminum, galvanized, stainless steel or rust-preventative coated nails or staples or other approved corrosion-resistant fasteners specified by the manufacturer and shall be fastened at both ends to a supporting component such as a nailing strip, fascia or sub-fascia component in accordance with Figure R704.2.1(1). Where the unsupported span of soffit panels is greater than 16 inches (406 mm), intermediate nailing strips shall be provided in accordance with Figure R704.2.1(2). Vinyl and aluminum soffit panels shall be installed in accordance with the manufacturer’s installation instructions. Fascia covers shall be installed in accordance with the manufacturer’s installation instructions.

         12. (L) Figure R704.2.1(1) (relating to typical single-span vinyl and aluminum exterior soffit panel support) is modified to read as follows:

             

         13. (M) Figure R704.2.1(2) (relating to typical double-span vinyl and aluminum exterior soffit panel support) is modified to read as follows:

             

         14. (N) Section R704.2.2 (relating to fiber-cement soffit panels) is (1) re-titled ‘‘Fiber-cement exterior soffit panels[;]’’ and (2) references to ‘‘soffit panels’’ therein are changed to ‘‘exterior soffit panels[.]’’
         15. (O) Section R704.2.3 (relating to hardboard soffit panels) is (1) re-titled ‘‘Hardboard exterior soffit panels[;]’’ and (2) the term ‘‘soffit panel’’ therein is changed to ‘‘exterior soffit panel[.]’’
         16. (P) Section R704.2.4 (relating to wood structural panel soffit) is re-titled ‘‘Wood structural panel exterior soffit[.]’’
         17. (Q) Section R704.3 (relating to exterior soffit installation where the design wind pressure exceeds 30 psf) is (1) re-titled ‘‘Exterior soffit installation where the design wind pressure exceeds 30 psf[;]’’ and (2) the term ‘‘soffit’’ is changed to ‘‘exterior soffit’’ throughout.
         18. (R) Section R704.3.1 (relating to vinyl soffit panels) is (1) re-titled ‘‘Vinyl exterior soffit panels[;]’’ (2) all references to ‘‘soffit panels’’ therein are changed to ‘‘exterior soffit panels[;]’’ and (3) the final sentence beginning ‘‘[f]ascia covers’’ is struck in its entirety.
         19. (S) Section R704.3.2 (relating to fiber-cement soffit panels) is (1) re-titled ‘‘Fiber-cement exterior soffit panels[;]’’ and (2) the term ‘‘soffit panels’’ therein is changed to ‘‘exterior soffit panels[.]’’
         20. (T) Section R704.3.3 (relating to hardboard soffit panels) is (1) re-titled ‘‘Hardboard exterior soffit panels[;]’’ and (2) the term ‘‘soffit panels’’ therein is changed to ‘‘exterior soffit panels[.]’’
         21. (U) Section R704.3.4 (relating to wood structural panel soffit) is (1) re-titled ‘‘Wood structural panel exterior soffit[;]’’ and (2) the term ‘‘panel soffits’’ therein is changed to ‘‘panel exterior soffits[.]’’
         22. (V) Table R704.3.4 (relating to prescriptive alternative for wood structural panel soffit) is modified to read as follows:
         23. (W) Section R802.3 (relating to ridge) is modified by striking ‘‘or column.’’ at the end of the second sentence and inserting ‘‘column, or girder.’’
         24. (X) Section R806.1 (relating to ventilation required) is modified by striking ‘‘and shall be protected to prevent the entry of birds, rodents, snakes and other similar creatures’’ from the end of the section.
         25. (Y) Section R806.3 (relating to vent and insulation clearance) is modified by striking ‘‘blocking, bridging and insulation shall not block’’ and inserting ‘‘nothing shall block’’ in the first sentence.
         26. (Z) Table N1102.1.2 (relating to maximum assembly U-factors and fenestration requirements) is modified to read as follows:
         27. (AA) Table N1102.1.3 (relating to insulation minimum R-values and fenestration requirements by component) is modified to read as follows:

         28. (BB) Section N1103.5.1.1 (relating to circulation systems) is modified to add the following exception:

             Exception: Where the entire hot water piping system (both supply and return) are insulated with a minimum R3 insulation, the stated controls shall not be required.

         29. (CC) Table N1105.2 (relating to requirements for total building performance) is modified to read as follows:

             Sectiona	Title
             General
             N1101.14	Certificate
             Building Thermal Envelope
             N1102.1.1	Vapor retarder
             N1102.2.3	Eave baffle
             N1102.2.4.1	Access hatches and doors
             N1102.2.10.1	Crawl space wall insulation installation
             N1102.4.1.1	Installation
             N1102.4.1.2	Testing
             N1102.5	Maximum fenestration U-factor and SHGC
             Mechanical
             N1103.1	Controls
             N1103.3, including N1103.3.1, except Sections N1103.3.2, N1103.3.3 and N1103.3.6	Ducts
             N1103.4	Mechanical system piping insulation
             N1103.5.1	Heated water circulation and temperature maintenance systems
             N1103.5.3	Drain water heat recovery units
             N1103.6	Mechanical ventilation
             N1103.7	Equipment sizing and efficiency rating
             N1103.8	Systems serving multiple dwelling units

             Sectiona	Title
             N1103.9	Snow melt system controls
             N1103.10	Energy consumption of pools and spas
             N1103.11	Portable spas
             N1103.12	Residential pools and permanent residential spas
             Electrical Power and Lighting Systems
             N1104.1	Lighting equipment
             N1104.2	Interior lighting controls
             a. Reference to a code section includes all the relative subsections except as indicated in the table.

         30. (DD) Section N1105.3.2.2 (relating to compliance report for certificate of occupancy) is modified by striking ‘‘and the title page of the building plans’’ from paragraph 2.
         31. (EE) Table N1106.2 (relating to requirements for energy rating index) is modified to read as follows:
         32. (FF) Section N1108.1 (relating to scope) is modified by striking ‘‘in accordance with Section N1101.13.5[.]’’
         33. (GG) Section N1108.2 (relating to additional efficiency package options) is modified to strike ‘‘for compliance with Section N1101.13.5[.]’’
         34. (HH) Section G2427.2.2 (relating to appliances with integral vents) is modified to strike the phrase ‘‘Items 1 and 2’’ from the end of the sentence.
         35. (II) Section G2427.5.1 (relating to factory-built chimneys) is modified by inserting ‘‘and installed in accordance with manufacturer’s instructions’’ after ‘‘UL 103[.]’’
         36. (JJ) Section G2427.5.4 (relating to size of chimneys) is modified with respect to method 3 by inserting ‘‘shall be not less than the area of the larger draft hood outlet plus 50 percent of the area of the smaller draft hood outlet, nor greater than seven times the smallest draft hood outlet’’ after ‘‘draft hoods[.]’’
         37. (KK) Section G2427.5.10 (relating to insulation shield) is modified by adding the following sentence at the end of the section: ‘‘Insulation shields provided as part of a listed chimney system shall be installed in accordance with the manufacturer’ installation instructions.’’
         38. (LL) Section E3601.8 (relating to emergency disconnects) is modified with respect to its first sentence by inserting ‘‘detached’’ between ‘‘two-family’’ and ‘‘dwelling units[.]’’
         39. (MM) Section E3905.8 (relating to boxes at fan outlets) is modified by striking ‘‘in a location that is acceptable’’ from the third sentence.
         40. (NN) Section E4004.5 (relating to means of support) is modified by replacing ‘‘E3906.12’’ with ‘‘E3905.6.3[.]’’
      5. (v) {Reserved}.

      6. (vi) The following previously adopted provisions of the ‘‘International Residential Code of 2015’’ remain in effect as follows:

         1. (A) Section R314.4 (relating to interconnection).
         2. (B) Section R325.5 (relating to openness) as modified by (1) striking ‘‘42 inches (1,067 mm)’’ and inserting ‘‘36 inches (914 mm)’’; and (2) striking the second exception.
         3. (C) Section R806.2 (relating to minimum vent area).
         4. (D) Section N1105.4.1 (relating to compliance software tools).
         5. (E) Section N1105.4.2 (relating to compliance report).
         6. (F) Section N1105.6 (relating to calculation software tools).
         7. (G) Section N1105.6.1 (relating to minimum capabilities).
         8. (H) Section N1105.6.2 (relating to specific approval).
         9. (I) Section N1105.6.3 (relating to input values).
         10. (J) Section N1106.3 (relating to energy rating index).
         11. (K) Section N1106.3.1 (relating to ERI reference design).
         12. (L) Section M1305.1.3.2 (relating to excavations).
         13. (M) Section M1411.6.1 (relating to refrigerant line insulation protection).
         14. (N) Section P2903.5 (relating to water hammer).
         15. (O) Section E3901.11 (relating to foyers) as modified by replacing ‘‘3 feet (914 mm)’’ with ‘‘6 feet (1,829 mm)’’ and requiring a minimum of one receptacle.
      7. (vii) {Reserved}.

      8. (viii) The following previously adopted provisions of the ‘‘International Residential Code of 2018’’ remain in effect as follows:

         1. (A) Section R311.7.4 (relating to walkline) as modified by adding figure R311.7.4 (relating to winder tread and landing detail).

            

         2. (B) Section R703.7 (relating to exterior plastic, (stucco)) as modified by striking ‘‘ASTM C926, ASTM C1063’’ and inserting ‘‘ASTM C926-2018B, ASTM C1063-2018B[.]’’
         3. (C) Section N1103.3.3 (relating to duct testing).
         4. (D) Section N1103.3.4 (relating to duct leakage).
         5. (E) Section N1104.1 (relating to lighting equipment, (mandatory)).
         6. (F) Section N1104.1.1 (relating to lighting equipment, (mandatory)).
         7. (G) Section N1104.1.2 (relating to fuel gas lighting equipment).
         8. (H) Section N1105.4.2.1 (relating to compliance report for permit application).

         9. (I) Table N1105.5.2(1) (relating to specifications for the standard reference and proposed designs) is adopted to read as follows; citations therein correspond to provisions in the ‘‘International Residential Code of 2021’’:

            For SI: 1 square foot = 0.93 m 2, 1 British thermal unit = 1055 J, 1 pound per square foot = 4.88 kg/ m2, 1 gallon (US) = 3.785 L, °C = (°F - 32)1.8, 1 degree = 0.79 rad. a. Where required by the building official, testing shall be conducted by an approved party. Hourly calculations as specified in the ASHRAE Handbook of Fundamentals, or the equivalent, shall be used to determine the energy loads resulting from infiltration. b. The combined air exchange rate for infiltration and mechanical ventilation shall be determined in accordance with Equation 43 of 2001 ASHRAE Handbook of Fundamentals, page 26.24 and the ‘‘Whole- house Ventilation’’ provisions of 2001 ASHRAE Handbook of Fundamentals, page 26.19 for intermittent mechanical ventilation. c. Thermal storage element shall mean a component that is not part of the floors, walls, or ceilings that is part of a passive solar system, and that provides thermal storage such as enclosed water columns, rock beds, or phase-change containers. A thermal storage element shall be in the same room as fenestration that faces within 15 degrees (0.26 rad) of true south, or shall be connected to such a room with pipes or ducts that allow the element to be actively charged. d. For a proposed design with multiple heating, cooling or water heating systems using different fuel types, the applicable standard reference design system capacities and fuel types shall be weighted in accordance with their respective loads as calculated by accepted engineering practice for each equipment and fuel type present. e. For a proposed design without a proposed heating system, a heating system having the prevailing federal minimum efficiency shall be assumed for both the standard reference design and proposed designs. f. For a proposed design home without a proposed cooling system, an electric air conditioner having the prevailing federal minimum efficiency shall be assumed for both the standard reference design and the proposed design. g. For a proposed design with a nonstorage-type water heater, a 40-gallon storage-type water heater having the prevailing federal minimum energy factor for the same fuel as the predominant heating fuel type shall be assumed. For a proposed design without a proposed water heater, a 40-gallon storage-type water heater with the prevailing federal minimum efficiency for the same fuel as the predominant heating fuel type shall be assumed for both the proposed design and standard reference design. h. For residences with conditioned basements, R-2 and R-4 residences, and for townhouses, the following formula shall be used to determine glazing area: AF = AS x FA x F

            where: AF = Total glazing area. AS = Standard reference design total glazing area. FA = (above-grade thermal boundary gross wall area)/(above-grade boundary wall area + 0.5 x below-grade boundary wall area) F = (above-grade thermal boundary wall area)/(above-grade thermal boundary wall area + common wall area) or 0.56, whichever is greater. and where: Thermal boundary wall is any wall that separates conditioned space from unconditioned space or ambient conditions. Above-grade thermal boundary wall is any thermal boundary wall component not in contact with soil. Below-grade boundary wall is any thermal boundary wall in soil contact. Common wall area is the area of walls shared with an adjoining dwelling unit. L and CFA are in the same units.

         10. (J) Section E3901.4.2 (relating to island countertop spaces).
         11. (K) Section E4002.11 (relating to bathtub and shower space).
   8. (8) The ‘‘International Fire Code of 2021’’ only to the extent it is referenced by other ICC codes adopted in this chapter.

   9. (9) The ‘‘International Energy Conservation Code of 2021’’ is adopted as follows:

      1. (i) {Reserved}.
      2. (ii) {Reserved}.
      3. (iii) {Reserved}.
      4. (iv) {Reserved}.

      5. (v) With respect to the Commercial Provisions, the following provisions are adopted:

         1. (A) Section C105.2.6 (relating to final inspection) is modified to read: ‘‘C105.2.6 Final inspection. The building shall have a final inspection and not be occupied until approved.’’
         2. (B) Section C402.5.5 (relating to rooms containing fuel-burning appliances) is modified by (1) changing exception number 1 to read: ‘‘Direct vent appliances with both intake and exhaust pipes installed continuous to the outside.’’ and (2) designating the provided exception as exception number 2.
         3. (C) Section C405.11 (relating to automatic receptacle control) is modified by changing ‘‘shall’’ to ‘‘may’’ in the first sentence.
         4. (D) Section C405.11.1 (relating to automatic receptacle control function) is modified by changing ‘‘20 minutes’’ to ‘‘120 minutes’’ in subparagraphs 2.2 and 2.3.

      6. (vi) With respect to the Residential Provisions the following provisions are adopted:

         1. (A) Section R202 is amended by inserting the following definition: ‘‘Framing Factor. The fraction of the total building component area that is structural framing.’’
         2. (B) Section R401.2.5 (relating to additional energy efficiency) is excluded.

         3. (C) Table R402.1.2 (relating to maximum assembly U-factors and fenestration requirements) is modified to read as follows:

            Climate E-zone	Fenestra- tion U-factorf	Skylight U-factor	Glazed Fenestra- tion SHGCd, e	Ceiling U-factor	Frame Wall U-value	Mass Wall U-valueb	Floor U-factor	Base- mentc Wall U-value	Crawl Spacec Wall U-factor
            1	0.50	0.75	0.25	0.035	0.084	0.197	0.064	0.360	0.477
            2	0.40	0.65	0.25	0.030	0.084	0.165	0.064	0.360	0.477
            3	0.32	0.55	0.25	0.030	0.060	0.098	0.047	0.091c	0.136
            4 except Marine	0.30	0.55	0.40	0.026	0.060	0.098	0.047	0.059	0.065
            5 and Marine 4	0.30	0.55	NR	0.026	0.051	0.082	0.033	0.050	0.055
            6	0.30	0.55	NR	0.026	0.045	0.060	0.033	0.050	0.055
            7 and 8	0.30	0.55	NR	0.026	0.045	0.057	0.028	0.050	0.055
            a. Nonfenestration U-factors shall be obtained from measurement, calculation or an approved source. b. Mass walls shall be in accordance with Section R402.2.5. Where more than half the insulation is on the interior, the mass wall U-factors shall not exceed 0.17 in Climate Zone 1, 0.14 in Climate Zone 2, 0.12 in Climate Zone 3, 0.087 in Climate Zone 4 except Marine, 0.065 in Climate Zone 5 and Marine 4, and 0.057 in Climate Zones 6 through 8. c. In warm-humid locations as defined by Figure R301.1 and Table R301.1, the basement wall U-factor shall not exceed 0.360. d. The SHGC column applies to all glazed fenestration. Exception: In Climate Zones 0 through 3, skylights shall be permitted to be excluded from glazed fenestration SHGC requirements provided that the SHGC for such skylights does not exceed 0.30. e. There are no SHGC requirements in the Marine Zone. f. A maximum U-factor of 0.32 shall apply in Marine Climate Zone 4 and Climate Zones 5 through 8 to vertical fenestration products installed in buildings located either: 1. Above 4,000 feet in elevation above sea level, or 2. In windborne debris regions where protection of openings is required by Section R301.2.1.2 of the International Residential Code.

         4. (D) Table R402.1.3 (relating to insulation minimum R-values and fenestration requirements by component) is modified to read:

            Climate Zone	Fenestra- tion U-factorb	Skylightb U-factor	Glazed Fenestra- tion SHGCb, e	Ceiling R-factor	Wood Frame Wall R-value	Mass Wall R-valuei	Floor R-value	Base- mentc Wall R-value	Slabd R-value & Depth	Crawl Spacec Wall R-value
            1	NR	0.75	0.25	30	13	3/4	13	0	0	0
            2	0.40	0.65	0.25	38	13	4/6	13	0	0	0
            3	0.32	0.55	0.25	38	20 or 13 + 5h	8/13	19	5/13f	0	5/13
            4 except Marine	0.32	0.55	0.40	49	20 or 13 + 5h	8/13	19	10/13	10, 2ft	10/13
            5 and Marine 4	0.30	0.55	NR	49	23 or 13 + 7.5h or 20 + 3.8h	13/17	30g	15/19	10, 4ft or 15, 3ft	15/19
            6	0.30	0.55	NR	49	20 + 5h or 13 + 10h	15/20	30g	15/19	10, 4ft	15/19
            7 and 8	0.30	0.55	NR	49	20 + 5h or 13 + 10h	19/21	30g	15/19	10, 4ft	15/19
            For SI: 1 foot = 304.8 mm NR = Not required a. R-values are minimums. U-factors and SHGC are maximums. Where insulation is installed in a cavity that is less than the label or design thickness of the insulation, the installed R-value of the insulation shall be not less than the R-value specified in the table. b. The fenestration U-factor column excludes skylights. The SHGC column applies to all glazed fenestration. Exception: In Climate Zones 1 through 3, skylights shall be permitted to be excluded from glazed fenestration SHGC requirements provided that the SHGC for such skylights does not exceed 0.30. c. ‘‘10/13’’ means R-10 continuous insulation on the interior or exterior of the home or R-13 cavity insulation on the interior of the basement wall. ‘‘15/19’’ means R-15 continuous insulation on the interior or exterior of the home or R-19 cavity insulation on the interior of the basement wall. Alternatively, compliance with ‘‘15/19’’ shall be R-13 cavity insulation on the interior of the basement wall plus R-5 continuous insulation on the interior or exterior of the home. d. R-5 insulation shall be provided under the full slab area of a heated slab in addition to the required slab edge insulation R-value for slabs, as indicated in the table. The slab edge insulation for heated slabs shall not be required to extend below the slab. e. There are no SHGC requirements in the Marine Zone. f. Basement wall insulation shall not be required in warm-humid locations as defined by Figure R301.1 and Table R301.1. g. Alternatively, insulation sufficient to fill the framing cavity providing not less than an R-value of R-19. h. The first value is cavity insulation, the second value is continuous insulation. Therefore, as an example, ‘‘13+5’’ means R-13 cavity insulation plus R-5 continuous insulation. i. Mass walls shall be in accordance with Section R402.2.5. The second R-value applies where more than half of the insulation is on the interior of the mass wall.

         5. (E) Section R403.3.5 (relating to duct testing) is modified as follows:

            1. (I) The section is re-titled ‘‘Duct testing (Mandatory)[;]’’

            2. (II) Two exceptions are inserted between paragraph 2 and the paragraph beginning ‘‘A written report’’ to read as follows:

               Exceptions:

               1. A duct air-leakage test shall not be required where the ducts and air handlers are located entirely within the building thermal envelope.

               2. A duct air-leakage test shall not be required for ducts serving heat or energy recovery ventilators that are not integrated with ducts serving heating or cooling systems.

            3. (III) The term ‘‘code official’’ is replaced with ‘‘building official’’; and
            4. (IV) The exception at the end of the section is struck.
         6. (F) Section R403.3.6 (relating to duct leakage) is modified as by re-titling the section ‘‘Duct leakage (Prescriptive)’’; and striking the third paragraph.
         7. (G) Section R403.3.7 (relating to building cavities) is modified to read: ‘‘R403.3.7 Building cavities (Mandatory). Building framing cavities shall not be used as supply ducts.’’
         8. (H) Section R403.5.1.1 (relating to circulation systems) is modified to add the following exception at the end of the section: ‘‘Exception: Where the entire hot water piping system (both supply and return) are insulated with a minimum R3 insulation, the stated controls shall not be required.’’
         9. (I) Section R404.1 (relating to lighting equipment) is modified to read: ‘‘R404.1 Lighting equipment (Mandatory). Not less than 90 percent of the permanently installed lighting fixtures shall contain only high-efficiency lamps.’’
         10. (J) Section R404.1.1 (relating to exterior lighting) is modified to read: ‘‘R404.1.1 Lighting equipment (Mandatory). Fuel gas lighting systems shall not have continuously burning pilot lights.’’
         11. (K) Section R404.1.2 (relating to fuel gas lighting equipment) is excluded.
         12. (L) Section R404.2 (relating to interior lighting controls) is excluded.
         13. (M) Section R404.3 (relating to exterior lighting controls) is excluded.

         14. (N) Table R405.2 (relating to requirements for total building performance) is modified to read as follows:

             Sectiona	Title
             General
             R401.3	Certificate
             Building Thermal Envelope
             R402.1.1	Vapor retarder
             R402.2.3	Eave baffle
             R402.2.4.1	Access hatches and doors
             R402.2.10.1	Crawl space wall insulation installation
             R402.4.1.1	Installation
             R402.4.1.2	Testing
             R402.5	Maximum fenestration U-factor and SHGC
             Mechanical
             R403.1	Controls
             R403.3, including R403.3.1, except Sections R403.3.2, R403.3.3 and R403.3.6	Ducts
             R403.4	Mechanical system piping insulation
             R403.5.1	Heated water circulation and temperature maintenance systems
             R403.5.3	Drain water heat recovery units
             R403.6	Mechanical ventilation
             R403.7	Equipment sizing and efficiency rating
             R403.8	Systems serving multiple dwelling units
             R403.9	Snow melt system controls
             R403.10	Energy consumption of pools and spas
             R403.11	Portable spas
             R403.12	Residential pools and permanent residential spas
             Electrical Power and Lighting Systems
             R404.1	Lighting equipment
             R404.2	Interior lighting controls
             a. Reference to a code section includes all the relative subsections except as indicated in the table.

         15. (O) Section R405.3.2 (relating to compliance report) is modified to read as follows:

             R405.3.2 Compliance report. Compliance software tools shall generate a report that documents that the proposed design complies with Section R405.2. A compliance report on the proposed design shall be submitted with the application for the building permit. Upon completion of the building, a compliance report based on the as-built condition of the building shall be submitted to the code official before a certificate of occupancy is issued. Batch sampling of buildings to determine energy code compliance for all buildings in the batch shall be prohibited.

             Compliance reports shall include information in accordance with Sections R405.3.2.1 and R405.3.2.2. Where the proposed design of a building could be built on different sites where the cardinal orientation of the building on each site is different, compliance of the proposed design for the purposes of the application for the building permit shall be based on the worst-case orientation, worst-case configuration, worst-case building air leakage and worst case duct leakage. Such worst-case parameters shall be used as inputs to the compliance software for energy analysis.

         16. (P) Section R405.3.2.1 (relating to compliance report for permit application) is modified by striking and replacing numbered paragraphs 2—6 with the following:

             2. A statement indicating that the proposed design complies with Section R405.4.

             3. An inspection checklist documenting the building component characteristics of the proposed design as indicated in Table R405.4.2(1). The inspection checklist shall show results for both the standard reference design and the proposed design with user inputs to the compliance software to generate the results.

             4. A site-specific energy analysis report that is in compliance with Section R405.4.

             5. The name of the individual performing the analysis and generating the report.

             6. The name and version of the compliance software tool.

         17. (Q) Section R405.3.2.2 (relating to compliance report for certificate of occupancy) is modified by striking ‘‘and the title page of the building plans’’ from paragraph 2.

         18. (R) Table R405.4.2(1) (relating to specifications for the standard reference and proposed designs) is modified to read as follows:

             Building Component	Standard Reference Design	Proposed Design
             Above-grade walls	Type: mass where the proposed wall is a mass wall; otherwise wood frame.	As proposed
             Gross area: same as proposed.	As proposed
             U-factor: as specified in Table R402.1.2.	As proposed
             Solar absorptance = 0.75.	As proposed
             Emittance = 0.90.	As proposed
             Basement and crawl space walls	Type: same as proposed.	As proposed
             Gross area: same as proposed.	As proposed
             U-factor: as specified in Table R402.1.2, with the insulation layer on the interior side of the walls.	As proposed
             Above-grade floors	Type: wood frame.	As proposed
             Gross area: same as proposed.	As proposed
             U-factor: as specified in Table R402.1.2.	As proposed
             Ceilings	Type: wood frame.	As proposed
             Gross area: same as proposed.	As proposed
             U-factor: as specified in Table R402.1.2.	As proposed
             Roofs	Type: composition shingle on wood sheathing.	As proposed
             Gross area: same as proposed.	As proposed
             Solar absorptance = 0.75.	As proposed
             Emittance = 0.90.	As proposed
             Attics	Type: vented with an aperture of 1 ft2 per 300 ft2 of ceiling area.	As proposed
             Foundations	Type: same as proposed.	As proposed
             Foundation wall area above and below grade and soil characteristics: same as proposed.	As proposed
             Opaque doors	Area: 40 ft2.	As proposed
             Orientation: North.	As proposed
             U-factor: same as fenestration as specified in Table R402.1.2.	As proposed
             Vertical fenestration other than opaque doors	Total areah = (c) The proposed glazing area, where the proposed glazing area is less than 15 percent of the conditioned floor area. (d) 15 percent of the conditioned floor area, where the proposed glazing area is 15 percent or more of the conditioned floor area.	As proposed
             Orientation: equally distributed to four cardinal compass orientations (N, E, S & W).	As proposed
             U-factor: as specified in Table R402.1.2.	As proposed
             SHGC: as specified in Table N1102.1.2 except for climate zones without an SHGC requirement, the SHGC shall be equal to 0.40.	As proposed
             Interior shade fraction: 0.92 - (0.21 x SHGC for the standard reference design).	Interior shade fraction: 0.92 - (0.21 x SHGC as proposed)
             External shading: none.	As proposed
             Skylights	None.	As proposed
             Thermally isolated sunrooms	None.	As proposed
             Air exchange rate	The air leakage rate at a pressure of 0.2 inch w.g. (50 Pa) shall be Climate Zones 1 and 2: 5 air changes per hour. Climate Zones 3 through 8: 3 air changes per hour. The mechanical ventilation rate shall be in addition to the air leakage rate and shall be the same as in the proposed design, but not greater than 0.01 x CFA + 7.5 x (Nbr + 1) where: CFA = conditioned floor area, ft2. Nbr = number of bedrooms. Energy recovery shall not be assumed for mechanical ventilation.	The measured air exchange rate.a The mechanical ventilation rateb shall be in addition to the air leakage rate and shall be as proposed.
             Mechanical ventilation	Where mechanical ventilation is not specified in the proposed design: None. Where mechanical ventilation is specified in the proposed design, the annual vent fan energy use, in units of kWh/yr, shall equal (1/ef) x [0.0876 x CFA + 65.7 x (Nbr + 1)] where: ef = the minimum exhaust efficiency, as specified in Table R403.6.1, corresponding to a flow rate of 0.01 x CFA + 7.5 x (Nbr + 1). CFA = conditioned floor area, ft2. Nbr = number of bedrooms.	As proposed
             Internal gains	IGain, in units of Btu/day per dwelling unit, shall equal 17,900 + 23.8 x CFA + 4,104 x Nbr where: CFA = conditioned floor area, ft2. Nbr = number of bedrooms.	Same as standard reference design.
             Internal mass	Internal mass for furniture and contents: 8 pounds per square foot of floor area.	Same as standard reference design, plus any additional mass specifically designed as a thermal storage elementc but not integral to the building envelope or structure.
             Structural mass	For masonry floor slabs: 80 percent of floor area covered by R-2 carpet and pad, and 20 percent of floor directly exposed to room air.	As proposed
             For masonry basement walls, as proposed, but with insulation as specified in Table R402.1.3, located on the interior side of the walls.	As proposed
             For other walls, ceilings, floors, and interior walls: wood frame construction.	As proposed
             Heating systems d, e	For other than electric heating without a heat pump: as proposed. Where the proposed design utilizes electric heating without a heat pump, the standard reference design shall be an air source heat pump meeting the requirements of Section C403 of the IECC—Commercial Provisions. Capacity: sized in accordance with Section N1103.7.	As proposed
             Cooling systems d, f	As proposed. Capacity: sized in accordance with Section N1103.7.	As proposed
             Service water heating d, e, f, g	As proposed. Use: same as proposed design.	As proposed Use, in units of gal/day = 30 + (10 x Nbr) where: Nbr = number of bedrooms.
             Thermal distribution systems	Duct insulation in accordance with Section N1103.3.1. A thermal distribution system efficiency (DSE) of 0.88 shall be applied to both the heating and cooling system efficiencies for all systems other than tested duct systems. Exception: For nonducted heating and cooling systems that do not have a fan, the standard reference design thermal distribution system efficiency (DSE) shall be 1. For tested duct systems, the leakage rate shall be 4 cfm (113.3 L/min) per 100 ft2 (9.29 m2) of conditioned floor area at a pressure of differential of 0.1 inch w.g. (25 Pa).	Duct insulation: as proposed. As tested or, where not tested, as specified in Table R405.4.2(2).
             Thermostat	Type: Manual, cooling temperature setpoint = 75°F; Heating temperature setpoint = 72°F.	Same as standard reference design.
             For SI: 1 square foot = 0.93 m 2, 1 British thermal unit = 1,055 J, 1 pound per square foot = 4.88 kg/ m2, 1 gallon (US) = 3.785 L, C = (°F— 32)1.8, 1 degree = 0.79 rad. a. Where required by the building official, testing shall be conducted by an approved party. Hourly calculations as specified in the ASHRAE Handbook of Fundamentals, or the equivalent, shall be used to determine the energy loads resulting from infiltration. b. The combined air exchange rate for infiltration and mechanical ventilation shall be determined in accordance with Equation 43 of 2001 ASHRAE Handbook of Fundamentals, page 26.24 and the ‘‘Whole-house Ventilation’’ provisions of 2001 ASHRAE Handbook of Fundamentals, page 26.19 for intermittent mechanical ventilation. c. Thermal storage element shall mean a component that is not part of the floors, walls, or ceilings that is part of a passive solar system, and that provides thermal storage such as enclosed water columns, rock beds, or phase-change containers. A thermal storage element shall be in the same room as fenestration that faces within 15 degrees (0.26 rad) of true south, or shall be connected to such a room with pipes or ducts that allow the element to be actively charged. d. For a proposed design with multiple heating, cooling or water heating systems using different fuel types, the applicable standard reference design system capacities and fuel types shall be weighted in accordance with their respective loads as calculated by accepted engineering practice for each equipment and fuel type present. e. For a proposed design without a proposed heating system, a heating system having the prevailing federal minimum efficiency shall be assumed for both the standard reference design and proposed designs. f. For a proposed design home without a proposed cooling system, an electric air conditioner having the prevailing federal minimum efficiency shall be assumed for both the standard reference design and the proposed design. g. For a proposed design with a nonstorage-type water heater, a 40-gallon storage-type water heater having the prevailing federal minimum energy factor for the same fuel as the predominant heating fuel type shall be assumed. For a proposed design without a proposed water heater, a 40-gallon storage-type water heater with the prevailing federal minimum efficiency for the same fuel as the predominant heating fuel type shall be assumed for both the proposed design and standard reference design. h. For residences with conditioned basements, R-2 and R-4 residences, and for townhouses, the following formula shall be used to determine glazing area: AF = AS x FA x F where: AF = Total glazing area. AS = Standard reference design total glazing area. FA = (above-grade thermal boundary gross wall area)/(above-grade boundary wall area + 0.5 x below-grade boundary wall area) F = (above-grade thermal boundary wall area)/(above-grade thermal boundary wall area + common wall area) or 0.56, whichever is greater. and where: Thermal boundary wall is any wall that separates conditioned space from unconditioned space or ambient conditions. Above-grade thermal boundary wall is any thermal boundary wall component not in contact with soil. Below-grade boundary wall is any thermal boundary wall in soil contact. Common wall area is the area of walls shared with an adjoining dwelling unit. L and CFA are in the same units.

         19. (S) Table R406.2 (relating to requirements for energy rating index) is modified to read as follows:

             Sectiona	Title
             General
             R401.3	Certificate
             Building Thermal Envelope
             R402.1.1	Vapor retarder
             R402.2.3	Eave baffle
             R402.2.4.1	Access hatches and doors
             R402.2.10.1	Crawl space wall insulation installation
             R402.4.1.1	Installation
             R402.4.1.2	Testing
             Mechanical
             R403.1	Controls
             R403.3, except Sections R403.3.2, R403.3.3 and R403.3.6	Ducts
             R403.4	Mechanical system piping insulation
             R403.5.1	Heated water circulation and temperature maintenance systems
             R403.5.3	Drain water heat recovery units
             R403.6	Mechanical ventilation
             R403.7	Equipment sizing and efficiency rating
             R403.8	Systems serving multiple dwelling units
             R403.9	Snow melt system controls

             Sectiona	Title
             R403.10	Energy consumption of pools and spas
             R403.11	Portable spas
             R403.12	Residential pools and permanent residential spas
             Electrical Power and Lighting Systems
             R404.1	Lighting equipment
             R404.2	Interior lighting controls
             R406.3	Building thermal envelope
             a. Reference to a code section includes all the relative subsections except as indicated in the table.

         20. (T) Section R406.3 (relating to building thermal envelope) is excluded.
         21. (U) Section R406.3.1 (relating to on-site renewables are not included) is excluded.
         22. (V) Section R406.3.2 (relating to on-site renewables are included) is excluded.

         23. (W) Section R406.4 (relating to energy rating index) is modified to read:

             R406.4 Energy rating index. The Energy Rating Index (ERI) shall be a numerical integer value that is based on a linear scale constructed such that the ERI reference design has an Index value of 100 and a residential building that uses no net purchased energy has an Index value of 0. Each integer value on the scale shall represent a 1 percent change in the total energy use of the rated design relative to the total energy use of the ERI reference design. The ERI shall consider all energy used in the residential building.

         24. (X) The following provision is added as Section R406.4.1:

             R406.4.1 ERI reference design. The ERI reference design shall be configured such that it meets the minimum requirements of the 2006 International Energy Conservation Code prescriptive requirements. The proposed residential building shall be shown to have an annual total normalized modified load less than or equal to the annual total loads of the ERI reference design.

         25. (Y) Section R406.7.1 (relating to compliance software tools) is modified to read:

             R406.7.1 Compliance software tools. Documentation verifying that the methods and accuracy of the compliance software tools conform to the provisions of this section shall be provided to the code official.

         26. (Z) Section R406.7.5 (relating to specific approval) is excluded.
         27. (AA) Section R406.7.6 (relating to input values) is excluded.

         28. (BB) The following section is added as Section R406.8:

             R406.8 Calculation software tools. Calculation software, where used, shall be in accordance with Sections R406.8.1 through R406.8.3.

         29. (CC) The following previously adopted section is added as Section R406.8.1:

             R406.8.1 Minimum capabilities. Calculation procedures used to comply with this section shall be software tools capable of calculating the ERI as described in Section R406.3, and shall include the following capabilities:

             1. Computer generation of the ERI reference design using only the input for the rated design.

             The calculation procedure shall not allow the user to directly modify the building component characteristics of the ERI reference design.

             2. Calculation of whole-building, as a single zone, sizing for the heating and cooling equipment in the ERI reference design residence in accordance with Section R403.7.

             3. Calculations that account for the effects of indoor and outdoor temperatures and part-load ratios on the performance of heating, ventilating and air conditioning equipment based on climate and equipment sizing.

             4. Printed code official inspection checklist listing each of the rated design component characteristics determined by the analysis to provide compliance, along with their respective performance ratings.

         30. (DD) The following section is added as Section R406.8.2:

             R406.7.2 (N1106.7.2) Specific approval. Performance analysis tools meeting the applicable sections of Section R406 (N1106) shall be approved. Tools are permitted to be approved based on meeting a specified threshold for a jurisdiction. The code official shall approve tools for a specified application or limited scope.

         31. (EE) The following section is added as Section R406.8.3:

             R406.7.3 (N1106.7.3) Input values. When calculations require input values not specified by Sections R402, R403, R404 and R405, those input values shall be taken from an approved source.

         32. (FF) Section R408.1 (relating to scope) is modified by striking ‘‘in accordance with Section R401.2.5[.]’’
         33. (GG) Section R408.2 (relating to additional efficiency package options) is modified by striking ‘‘for compliance with Section N1101.13.5[.]’’

   10. (10) The ‘‘International Existing Building Code of 2021’’ except:

       1. (i) The accessibility provisions contained in the following sections of the ‘‘International Existing Building Code of 2021’’ are excluded:

          1. (A) Section 301.5 (relating to compliance with accessibility).
          2. (B) Section 305 (relating to accessibility for existing buildings).
          3. (C) Section 1101.2 (relating to creation or extension of nonconformity).
          4. (D) Appendix B (relating to supplementary accessibility requirements for existing buildings and facilities).
       2. (ii) Section 1106 (relating to storm shelters) is excluded.
       3. (iii) {Reserved}.
   11. (11) The ‘‘International Wildland-Urban Interface Code of 2021.’’
   12. (12) Appendix E of the ‘‘International Building Code of 2018.’’
   13. (13) Appendix H of the ‘‘International Building Code of 2009.’’

   14. (14) The ‘‘International Swimming Pool and Spa Code of 2021,’’ except:

       1. (i) The following provisions are excluded:

          1. (A) Section [A] 108.2 (relating to schedule of permit fees).
          2. (B) Section [A] 108.3 (relating to permit valuations).
          3. (C) Section [A] 108.4 (relating to work commencing before permit issuance).
          4. (D) Section [A] 108.5 (relating to payment of fees related to permits).

       2. (ii) The following provisions of the ‘‘International Swimming Pool and Spa Code of 2018’’ remain in effect:

          1. (A) Section [A] 105.6.1 (relating to work commencing before permit issuance).
          2. (B) Section [A] 105.6.2 (relating to fee schedule).
2. (b) The code adopted under subsection (a)(8) is part of the Uniform Construction Code to the extent that it is referenced in Chapter 35 of the ‘‘International Building Code of 2021’’ under section 302(a)(1) of the act (35 P.S. § 7210.302(a)(1)). The provisions of the Uniform Construction Code apply if there is a difference between the Uniform Construction Code and the codes or standards adopted in subsection (a). This chapter’s administrative provisions govern under § 403.27(e) (relating to applicability and use of standards) if there is a conflict with the provisions of the codes relating to administration incorporated under subsection (a).
3. (c) Appendices to a code or standard listed in subsection (a) are not adopted in the Uniform Construction Code except for the appendices and resource information found in the ‘‘International Existing Building Code of 2021’’ and the appendices found in subsection (a)(12) and (13).

4. (d) A permit applicant may utilize one of the following prescriptive methods to demonstrate compliance with the energy conservation requirements of the Uniform Construction Code. The standards are those listed for the climatic zone of this Commonwealth where the building or structure is located:

   1. (1) The prescriptive methods for detached residential buildings contained in the ‘‘International Energy Conservation Code of 2021’’ compliance guide containing State maps, prescriptive energy packages and related software published by the United States Department of Energy, Building Standards and Guidelines Program (REScheck^TM) or ‘‘Pennsylvania’s Alternative Residential Energy Provisions.’’
   2. (2) The prescriptive methods for all other buildings or structures contained in the ‘‘International Energy Conservation Code of 2021’’ compliance guide containing State maps, prescriptive packages and related software published by the United States Department of Energy, Building Standards and Guidelines Program (COMcheck^TM).
5. (e) Construction of individual sewage disposal systems is governed under 25 Pa. Code Chapter 73 (relating to standards for onlot sewage treatment facilities).
6. (f) The repair, alteration, change of occupancy, addition and relocation of existing buildings must comply with Chapter 34 of the ‘‘International Building Code of 2021’’ or with the ‘‘International Existing Building Code of 2021.’’

Table R704.3.4Prescriptive Alternative for Wood StructuralPannel Soffit b, c, d, e Maximum Design Pressure(+ or - psf)MinimumPanelSpanRating MinimumPanelPerformanceCategory Nail Type andSize Fastenera Spacing Along Edges andIntermediate Supports GalvanizedSteel StainlessSteel 30 24/0 3/8 6d box(2 x 0.099 x 0.266 head diameter) 6f 4 40 24/0 3/8 6d box(2 x 0.099 x 0.266 head diameter) 6 4 50 24/0 3/8 6d box(2 x 0.099 x 0.266 head diameter)44 8d common(2 1/2 x 0.131 x 0.281 head diameter) 66 60 24/0 3/8 6d box(2 x 0.099 x 0.266 head diameter) 4 3 8d common(2 1/2 x 0.131 x 0.281 head diameter) 6 4 70 24/16 7/16 8d common(2 1/2 x 0.131 x 0.281 head diameter) 4 4 10d box(3 x 0.128 x 0.312 head diameter) 6 4 80 24/16 7/16 8d common(2 1/2 x 0.131 x 0.281 head diameter) 4 4 10d box(3 x 0.128 x 0.312 head diameter) 6 4 90 32/16 15/32 8d common(2 1/2 x 0.131 x 0.281 head diameter) 4 3 10d box(3 x 0.128 x 0.312 head diameter) 6 4 For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa a. Fasteners shall comply with Sections R703.3.2 and R703.3.3. b. Maximum spacing of soffit framing members shall not exceed 24 inches. c. Wood structural panels shall be of an exterior exposure grade. d. Wood structural panels shall be installed with strength axis perpendicular to supports with not fewer than two continuous spans. e. Wood structural panels shall be attached to soffit framing members with specific gravity of at least 0.35. Where the specific gravity of the wood species used for soffit framing members is greater than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, the fastener spacing shall be multiplied by 0.67 or the same fastener spacing as prescribed for galvanized steel nails shall be permitted to be used where RSRS-01 (2" x 0.099" x 0.266" head) nails replace 6d box nails and RSRS-03 (2-1/2" x 0.131" x 0.281" head) nails replace 8d common nails or 10d box nails. RSRS is a Roof Sheathing Ring Shank nail meeting the specifications in ASTM F1667. Framing members shall be minimum 2 x 3 nominal with the larger dimension in the cross section aligning with the length of fasteners to provide sufficient embedment depths. f. Spacing at intermediate supports shall not be greater than 12 inches on center.

Table N1102.1.2Maximum Assembly U-factorsa and Fenestration Requirements ClimateZone Fenestra-tion U-factorf SkylightU-factor GlazedFenestra-tionSHGCd,e CeilingU-factor FrameWallU-factor MassWallU-factorb FloorU-factor BasementWallU-factor CrawlSpaceWallU-factor 1 0.50 0.75 0.25 0.035 0.084 0.197 0.064 0.360 0.477 2 0.40 0.65 0.25 0.030 0.084 0.165 0.064 0.360 0.477 3 0.32 0.55 0.25 0.030 0.060 0.098 0.047 0.091c 0.136 4 except Marine 0.30 0.55 0.40 0.026 0.060 0.098 0.047 0.059 0.065 5 and Marine 4 0.30 0.55 NR 0.026 0.051 0.082 0.033 0.050 0.055 6 0.30 0.55 NR 0.026 0.045 0.060 0.033 0.050 0.055 7 and 8 0.30 0.55 NR 0.026 0.045 0.057 0.028 0.050 0.055 a. Nonfenestration U-factors shall be obtained from measurement, calculation or an approved source. b. Mass walls shall be in accordance with Section R402.2.5. Where more than half the insulation is on the interior, the mass wall U-factors shall not exceed 0.17 in Climate Zone 1, 0.14 in Climate Zone 2, 0.12 in Climate Zone 3, 0.087 in Climate Zone 4 except Marine, 0.065 in Climate Zone 5 and Marine 4, and 0.057 in Climate Zones 6 through 8. c. In warm-humid locations as defined by Figure R301.1 and Table R301.1, the basement wall U-factor shall not exceed 0.360. d. The SHGC column applies to all glazed fenestration. Exception: In Climate Zones 0 through 3, skylights shall be permitted to be excluded from glazed fenestration SHGC requirements provided that the SHGC for such skylights does not exceed 0.30. e. There are no SHGC requirements in the Marine Zone. f. A maximum U-factor of 0.32 shall apply in Marine Climate Zone 4 and Climate Zones 5 through 8 to vertical fenestration products installed in buildings located either: 1. Above 4,000 feet in elevation above sea level, or 2. In windborne debris regions where protection of openings is required by Section R301.2.1.2. of the International Residential Code.

Table N1102.1.3Insulation Minimum R-values and Fenestration Requirements by Componenta ClimateZoneFenestra-tionU-factorbSkylightbU-factorGlazedFenestra-tionSHGCb, eCeilingR-factorWoodFrameWallR-valueMassWallR-valueiFloorR-valueBase-mentcWallR-valueSlavdR-value& Depth CrawlSpacecWallR-value 1 NR 0.75 0.25 30 13 3/4 13 0 0 0 2 0.40 0.65 0.25 38 13 4/6 13 0 0 0 3 0.32 0.55 0.25 38 20 or 13 + 5h 8/13 19 5/13f 0 5/13 4 except Marine 0.32 0.55 0.40 49 20 or 13 + 5h 8/13 19 10/13 10, 2ft 10/13 5 and Marine 4 0.30 0.55 NR 49 23 or 13 + 7.5h or 20 + 3.8h 13/17 30g 15/19 10, 4ft or 15, 3ft 15/19 6 0.30 0.55 NR 49 20 + 5h or 13 + 10h 15/20 30g 15/19 10, 4ft 15/19 7 and 8 0.30 0.55 NR 49 20 + 5h or 13 + 10h 19/21 30g 15/19 10, 4ft 15/19 For SI: 1 foot = 304.8 mm NR = Not required a. R-values are minimums. U-factors and SHGC are maximums. Where insulation is installed in a cavity that is less than the label or design thickness of the insulation, the installed R-value of the insulation shall be not less than the R-value specified in the table. b. The fenestration U-factor column excludes skylights. The SHGC column applies to all glazed fenestration. Exception: In Climate Zones 1 through 3, skylights shall be permitted to be excluded from glazed fenestration SHGC requirements provided that the SHGC for such skylights does not exceed 0.30. c. ‘‘10/13’’ means R-10 continuous insulation on the interior or exterior of the home or R-13 cavity insulation on the interior of the basement wall. ‘‘15/19’’ means R-15 continuous insulation on the interior or exterior of the home or R-19 cavity insulation on the interior of the basement wall. Alternatively, compliance with ‘‘15/19’’ shall be R-13 cavity insulation on the interior of the basement wall plus R-5 continuous insulation on the interior or exterior of the home. d. R-5 insulation shall be provided under the full slab area of a heated slab in addition to the required slab edge insulation R-value for slabs, as indicated in the table. The slab edge insulation for heated slabs shall not be required to extend below the slab. e. There are no SHGC requirements in the Marine Zone. f. Basement wall insulation shall not be required in warm-humid locations as defined by Figure R301.1 and Table R301.1. g. Alternatively, insulation sufficient to fill the framing cavity providing not less than an R-value of R-19. h. The first value is cavity insulation, the second value is continuous insulation. Therefore, as an example, ‘‘13+5’’ means R-13 cavity insulation plus R-5 continuous insulation. i. Mass walls shall be in accordance with Section R402.2.5. The second R-value applies where more than half of the insulation is on the interior of the mass wall.

Table N1105.2Requirements for Total Building Performance

Table N1106.2Requirements for Energy Rating Index Sectiona Title General N1101.14 Certificate Building Thermal Envelope N1102.1.1 Vapor retarder N1102.2.3 Eave baffle N1102.2.4.1 Access hatches and doors N1102.2.10.1 Crawl space wall insulation installation N1102.4.1.1 Installation N1102.4.1.2 Testing Mechanical N1103.1 Controls N1103.3, except Sections N1103.3.2, N1103.3.3 and N1103.3.6 Ducts N1103.4 Mechanical system piping insulation N1103.5.1 Heated water circulation and temperature maintenance systems N1103.5.3 Drain water heat recovery units N1103.6 Mechanical ventilation N1103.7 Equipment sizing and efficiency rating N1103.8 Systems serving multiple dwelling units N1103.9 Snow melt system controls N1103.10 Energy consumption of pools and spas N1103.11 Portable spas N1103.12 Residential pools and permanent residential spas Electrical Power and Lighting Systems N1104.1 Lighting equipment N1104.2 Interior lighting controls N1106.3 Building thermal envelope a. Reference to a code section includes all the relative subsections except as indicated in the table.

Table N1105.5.2(1)Specifications for the Standard Reference and Proposed Designs BuildingComponentStandard Reference DesignProposed Design Above-grade walls Type: mass where the proposed wall is a mass wall; otherwise wood frame. As proposed Gross area: same as proposed. As proposed U-factor: as specified in Table N1102.1.2. As proposed Solar absorptance = 0.75. As proposed Emittance = 0.90. As proposed Basement and crawl space walls Type: same as proposed. As proposed Gross area: same as proposed. As proposed U-factor: as specified in Table N1102.1.2, with the insulation layer on the interior side of the walls. As proposed Above-grade floors Type: wood frame. As proposed Gross area: same as proposed. As proposed U-factor: as specified in Table N1102.1.2. As proposed Ceilings Type: wood frame. As proposed Gross area: same as proposed. As proposed U-factor: as specified in Table N1102.1.2. As proposed Roofs Type: composition shingle on wood sheathing. As proposed Gross area: same as proposed. As proposed Solar absorptance = 0.75. As proposed Emittance = 0.90. As proposed Attics Type: vented with an aperture of 1 ft2 per 300 ft2 of ceiling area. As proposed Foundations Type: same as proposed. As proposed Foundation wall area above and below grade and soil characteristics: same as proposed. As proposed Opaque doors Area: 40 ft2. As proposed Orientation: North. As proposed U-factor: same as fenestration as specified in Table N1102.1.2. As proposed Vertical fenestration other than opaque doors Total areah = (a) The proposed glazing area, where the proposed glazing area is less than 15 percent of the conditioned floor area. (b) 15 percent of the conditioned floor area, where the proposed glazing area is 15 percent or more of the conditioned floor area. As proposed Orientation: equally distributed to four cardinal compass orientations (N, E, S & W). As proposed U-factor: as specified in Table N1102.1.2. As proposed SHGC: as specified in Table N1102.1.2 except for climate zones without an SHGC requirement, the SHGC shall be equal to 0.40. As proposed Interior shade fraction: 0.92 - (0.21 x SHGC for the standard reference design). Interior shade fraction: 0.92 - (0.21 x SHGC as proposed) External shading: none. As proposed Skylights None. As proposed Thermally isolated sunrooms None. As proposed Air exchange rate The air leakage rate at a pressure of 0.2 inch w.g. (50 Pa) shall be: Climate Zones 1 and 2: 5 air changes per hour. Climate Zones 3 through 8: 3 air changes per hour. The mechanical ventilation rate shall be in addition to the air leakage rate and shall be the same as in the proposed design, but not greater than 0.01 x CFA + 7.5 x (Nbr + 1) where: CFA = conditioned floor area, ft2. Nbr = number of bedrooms. Energy recovery shall not be assumed for mechanical ventilation. The measured air exchange rate.a The mechanical ventilation rateb shall be in addition to the air leakage rate and shall be as proposed. Mechanical ventilation Where mechanical ventilation is not specified in the proposed design: None. Where mechanical ventilation is specified in the proposed design, the annual vent fan energy use, in units of kWh/yr, shall equal (1/ef) x [0.0876 x CFA + 65.7 x (Nbr + 1)] where: ef = the minimum exhaust efficiency, as specified in Table R403.6.1, corresponding to a flow rate of 0.01 x CFA + 7.5 x (Nbr + 1). CFA = conditioned floor area, ft2. Nbr = number of bedrooms. As proposed Internal gains IGain, in units of Btu/day per dwelling unit, shall equal 17,900 + 23.8 x CFA + 4,104 x Nbr where: CFA = conditioned floor area, ft2. Nbr = number of bedrooms. Same as standard reference design. Internal mass Internal mass for furniture and contents: 8 pounds per square foot of floor area. Same as standard reference design, plus any additional mass specifically designed as a thermal storage elementc but not integral to the building envelope or structure. Structural mass For masonry floor slabs: 80 percent of floor area covered by R-2 carpet and pad, and 20 percent of floor directly exposed to room air. As proposed For masonry basement walls, as proposed, but with insulation as specified in Table N1102.1.3, located on the interior side of the walls. As proposed For other walls, ceilings, floors, and interior walls: wood frame construction. As proposed Heating systemsd, e For other than electric heating without a heat pump: as proposed. Where the proposed design utilizes electric heating without a heat pump, the standard reference design shall be an air source heat pump meeting the requirements of Section C403 of the IECC—Commercial Provisions. Capacity: sized in accordance with Section N1103.7. As proposed Cooling systemsd, f As proposed. Capacity: sized in accordance with Section N1103.7. As proposed Service water heatingd, e, f, g As proposed. Use: same as proposed design. As proposedUse, in units of gal/day = 30 + (10 x Nbr) where: Nbr = number of bedrooms. Thermal distribution systems Duct insulation in accordance with Section N1103.3.1. A thermal distribution system efficiency (DSE) of 0.88 shall be applied to both the heating and cooling system efficiencies for all systems other than tested duct systems. Exception: For nonducted heating and cooling systems that do not have a fan, the standard reference design thermal DSE shall be 1. For tested duct systems, the leakage rate shall be 4 cfm (113.3 L/min) per 100 ft2 (9.29 m2) of conditioned floor area at a pressure of differential of 0.1 inch w.g. (25 Pa). Duct insulation: as proposed.As tested or, where not tested, as specified in Table N1105.4.2(2). Thermostat Type: Manual, cooling temperature setpoint = 75°F; Heating temperature setpoint = 72°F. Same as standard reference design.

Table R402.1.2Maximum Assembly U-factorsa and Fenestration Requirements

Table R402.1.3Insulation Minimum R-values and Fenestration Requirements by Componenta

Table R405.2Requirements for Total Building Performance

Table R405.4.2(1)Specifications for the Standard Reference and Proposed Designs

Table R406.2Requirements for Energy Rating Index

Authority

The provisions of this § 403.21 amended under sections 302 and 304(a)(1)—(3) of the Pennsylvania Construction Code Act (35 P.S. § § 7210.302 and 7210.304(a)(1)—(3)).

Source

The provisions of this § 403.21 amended December 15, 2006, effective December 31, 2006, 36 Pa.B. 7548; amended December 24, 2009, effective December 31, 2009, 39 Pa.B. 7196; amended December 21, 2012, effective December 31, 2012, 42 Pa.B. 7646; amended November 25, 2015, effective December 31, 2015, 45 Pa.B. 6813; amended May 6, 2016, effective May 7, 2016, 46 Pa.B. 2315; amended September 29, 2018, effective October 1, 2018, 48 Pa.B. 6261; amended November 2, 2018, effective November 3, 2018, 48 Pa.B. 6987; amended June 14, 2019, effective June 15, 2019, 49 Pa.B. 3077; amended December 24, 2021, effective December 25, 2021, 51 Pa.B. 7981; amended February 11, 2022, effective February 14, 2022, 52 Pa.B. 971; amended November 7, 2025, effective January 1, 2026, 55 Pa.B. 7701. Immediately preceding text appears at serial pages (408689) to (408695).

Notes of Decisions

The Department of Labor and Industry had the authority to adopt model codes to serve as basis for the Uniform Construction Code; this authority included the implied authority to incorporate an appendix of the International Residential Code setting standards for manufactured homes which the Department deemed relevant. DRB v. Department of Labor, 853 A.2d 8, 18, 19 (Pa. Cmwlth. 2004) aff’d 887 A.2d 1216 (Pa. 2005).

Cross References

This section cited in 34 Pa. Code § 403.2 (relating to other statutes or ordinances); 34 Pa. Code § 403.27 (relating to applicability and use of standards); 34 Pa. Code § 403.44 (relating to alternative construction materials and methods); and 34 Pa. Code § 403.102 (relating to municipalities electing to enforce the Uniform Construction Code).