The provisions of Section C402 of IECC-CE are adopted by reference with the following modifications:
1. Throughout the body of each provision of this section, reset the singular and plural forms of the following terms in italic type: "above-grade wall," "air barrier," "air curtain," "below-grade wall," "building thermal envelope," "commercial building," "conditioned space," "continuous insulation," "daylight responsive control," "daylight zone," "dwelling unit," "dynamic glazing," "enclosed space," "entrance door," "equipment room," "exterior wall," "fenestration," "fenestration area," "greenhouse," "infiltration," "internal curtain system," "net floor area," "opaque doors," "roof assembly," "rooftop monitor," "skylight," "sleeping unit," "solar heat gain coefficient (SHGC)," "testing unit enclosure area," "thermostat," "vertical fenestration," "visible transmittance (VT)," "walk-in cooler," and "walk-in freezer."
2. Revise Section C402.1 by deleting item 2 and replacing "skylight area" with "skylight fenestration area."
3. Revise the exception to Section C402.1.1.1, item 1 by replacing "Low energy" with "Low-energy."
4. Revise Section C402.1.2 by deleting item 5 and revising item 4 to read:
"Have an average wall and roof U-factor less than 0.200."
5. Revise Section C402.1.3 by replacing each "Group R" with "Group R."
6. Revise Table C402.1.3 by deleting all columns except "5 and Marine 4," deleting "and Marine 4," and deleting footnote c.
7. Revise Section C402.1.4 by replacing each "Group R" with "Group R."
8. Revise Table C402.1.4 by deleting all columns except "5 and Marine 4," deleting "and Marine 4," replacing "permitted" with "allowed" in footnote b, and deleting "in Climate Zones 0 through 6 and less than or equal to 0.36 in Climate Zones 7 and 8" in footnote h.
9. Revise Section C402.1.4.2 to read:
"C402.1.4.2 Thermal resistance of cold-formed steel assemblies.
U-factors of walls with cold-formed steel framed ceilings and walls shall be allowed to be determined in accordance with AISI S250 as modified herein.
1. Where the steel-framed wall contains no cavity insulation and uses continuous insulation to satisfy the U-factor maximum, the steel-framed wall member spacing is allowed to be installed at any on-center spacing.
2. Where the steel-framed wall contains framing at 24 inches (600 mm) on center with a 23% framing factor or framing at 16 inches (400 mm) on-center with a 25% framing factor, the next lower framing member spacing input values shall be used when calculating using AISI S250.
3. Where the steel-framed wall contains less than 23% framing factors the AISI S250 shall be used without any modifications.
4. Where the steel-framed wall contains other than standard C-shape framing members the AISI S250 calculation option for other than standard C-shape framing is allowed to be used."
10. Delete Equation 4-1.
11. Delete Table C402.1.4.2.
12. Revise Section C402.2.2 by replacing "permitted" with "allowed."
13. Revise the exceptions to Section C402.2.3 by replacing each "permitted" with "allowed."
14. Revise Section C402.2.5 by replacing each "below-grade exterior walls" with "below-grade walls."
15. Insert a new Section C402.2.8 to read:
"C402.2.8 Balconies and parapets.
See Section C605."
16. Revise Section C402.3 and its subparts to read:
"C402.3 Roof solar reflectance.
See Section 1515 of the Chicago Building Code."
17. Delete Table C402.3.
18. Delete Equation 4-3.
19. Revise Table C402.4 by deleting all columns except "5 and Marine 4," deleting "and Marine 4," and deleting "NR = No Requirement."
20. Revise Section C402.4.1 by replacing "skylight area" with "skylight fenestration area."
21. Revise Section C402.4.1.1 to read:
"C402.4.1.1 Increased vertical fenestration area with daylight responsive controls.
Not more than 40 percent of the gross above-grade wall area shall be vertical fenestration, provided that all of the following requirements are met:
1. In buildings with no more than two stories above grade plane: not less than 50 percent of the net floor area is within a daylight zone.
2. In buildings with three or more stories above grade plane: not less than 25 percent of the net floor area is within a daylight zone.
3. Daylight responsive controls are installed in daylight zones.
4. Visible transmittance (VT) of vertical fenestration is not less than 1.1 times solar heat gain coefficient (SHGC).
Exception: Fenestration that is outside the scope of NFRC 200 is not required to comply with Item 4."
22. Revise Section C402.4.1.2 by replacing "toplit" with "toplit."*
* Editor’s note – Coun. J. 9-21-22, p. 52080, Art. I, § 1, incorrectly numbered this and subsequent subsections as 4 through 19. Renumbered at the discretion of the editor. Future legislation will correct the numbering if needed.
23. Insert a new Section C402.4.1.3 and Equations 4-3a through 4-3d to read:
"C402.4.1.3 Orientation.
The fenestration area for vertical fenestration shall comply with either equations 4-3a and 4-3b or 4-3c and 4-3d.
Exceptions:
1. Buildings with shade on 75% of the east- and west-oriented vertical fenestration area from permanent projections, existing buildings, existing permanent infrastructure, or topography at 9 a.m. and 3 p.m., respectively, on the summer solstice (June 21).
2. Alterations and additions with no increase in vertical fenestration area.
3. Buildings where the west-oriented and east-oriented vertical fenestration area does not exceed 20% of the gross wall area for each of those facades and the actual SHGC for vertical fenestration on those facades is no greater than 90% of the maximum specified in Table C402.4.
Aw (At)/4 (Equation 4-3a)
Ae (At)/4 (Equation 4-3b)
Aw × SHGCw (At × SHGCc)/5 (Equation 4-3c)
Ae × SHGCe (At × SHGCc)/5 (Equation 4-3d)
where:
Ae = The fenestration area of east-oriented vertical fenestration (oriented within 45 degrees of true east to the south and within 22.5 degrees of true east to the north) in square feet.
Aw = The fenestration area of west-oriented vertical fenestration (oriented within 45 degrees of true west to the south and within 22.5 degrees of true west to the north) in square feet.
At = The total fenestration area of vertical fenestration in square feet, measured using the rough opening and including the glazing, sash and frame.
SHGCc = Maximum allowed SHGC from Table C402.4.
SHGCe = Actual SHGC for east-oriented vertical fenestration.
SHGCw = Actual SHGC for west-oriented vertical fenestration."
24. Revise Section C402.4.2 by replacing each "toplit" with "toplit."
25. Revise the exception to Section C402.4.2 by deleting item 1 and replacing "sidelit" with "sidelit."
26. Revise Section C402.4.3.1 to read:
"Skylights shall be allowed a maximum SHGC of 0.60 where located above daylight zones provided with daylight responsive controls."
27. Revise Section C402.4.3.2 to read:
"Where skylights are installed above daylight zones provided with daylight responsive controls, a maximum U- factor of 0.75 shall be allowed."
28. Revise Sections C402.4.3.3 and C402.4.3.4 by replacing "permitted" with "allowed."
29. Revise Section C402.4.4 by replacing "toplit" with "toplit."
30. Revise Section C402.4.5.2 to read:
"Opaque nonswinging doors that are horizontally hinged sectional doors with a single row of fenestration shall have an assembly U-factor less than or equal to 0.440, provided that the fenestration area is not less than 14 percent and not more than 25 percent of the total door area."
31. Delete the exception to Section C402.5.1.
32. Revise Section C402.5.1.1 by replacing "continuous" with "continuous" and "in places and changes in" with "at joints between dissimilar."
33. Delete all exceptions to Section C402.5.1.2.
34. Revise Table C402.5.4 by replacing "High-speed doors" with "High speed doors."
35. Revise the first sentence of Section C402.5.5 to read:
"Where combustion air is supplied through openings in an exterior wall to a room or space containing a space- conditioning fuel-burning appliance, one of the following shall apply:"
36. Revise the exception to Section C402.5.9 by replacing "Exceptions:" with "Exception:" and deleting item 1.
37. Revise exception 2 to Section C402.5.11 by deleting "where approved by the code official."