Energy Code Ace - Low-sloped roofs in Climate Zones 1 through 16 shall have:

SECTION 140.3 - PRESCRIPTIVE REQUIREMENTS FOR BUILDING ENVELOPES

A building complies with this section by being designed with and constructed to meet all prescriptive requirements in Subsection (a) and the requirements of Subsection (c) and (d) where they apply.

(a) Envelope component requirements.



1. Exterior roofs and ceilings. Exterior roofs and ceilings shall comply with each of the applicable requirements in this subsection:

A. Roofing Products. Shall meet the requirements of Section 110.8 and the applicable requirements of Subsections i through ii:

i. Nonresidential buildings:

a. Low-sloped roofs in climate zones 1 through 16 shall have:

A minimum aged solar reflectance of 0.63 and a minimum thermal emittance of 0.75; or
A minimum solar reflectance index (SRI) of 75.

Exception 1 to Section 140.3(a)1Aia: Wood-framed roofs in climate zones 3 and 5 are not required to comply with Section 140.3(a)1Aia if the roof assembly has a U-factor of 0.034 or lower.

Exception 2 to Section 140.3(a)1Aia: Roof constructions with a weight of at least 25 lb/ft² over the roof membrane are not required to comply with Section 140.3(a)1Aia.

Exception 3 to Section 140.3(a)1Aia: An aged solar reflectance less than 0.63 is allowed provided the maximum roof/ceiling U-factor in TABLE 140.3 is not exceeded.

b. Steep-sloped roofs:

In climate zones 1 and 3 shall have a minimum aged solar reflectance of 0.20 and a minimum thermal emittance of 0.75, or a minimum SRI of 16.
In climate zones 2 and 4 through 16 shall have a minimum aged solar reflectance of 0.25 and a minimum thermal emittance of 0.80, or a minimum SRI of 23.

ii. Guest rooms of hotel and motel buildings:

a. Low-sloped roofs in climate zones 9, 10, 11, 13, 14 and 15 shall have a minimum aged solar reflectance of 0.55 and a minimum thermal emittance of 0.75, or a minimum SRI of 64.

Exception to Section 140.3(a)1Aiia: Roof constructions with a weight of at least 25 lb/ft² over the roof membrane.

b. Steep-sloped roofs in climate zones 2 through 15 shall have a minimum aged solar reflectance of 0.20 and a minimum thermal emittance of 0.75, or a minimum SRI of 16.

TABLE 140.3 Roof/Ceiling Insulation Tradeoff For Aged Solar Reflectance – Nonresidential Buildings

Aged Solar Reflectance	Metal Building Climate Zone 1-16 U-factor	Wood framed and Other Climate Zone 6 - 8 U-factor	Wood Framed and Other All Other Climate Zones U-factor
0.62-0.56	0.038	0.045	0.032
0.55-0.46	0.035	0.042	0.030
0.45-0.36	0.033	0.039	0.029
0.35-0.25	0.031	0.037	0.028

Exception to Section 140.3(a)1A: Roof area covered by building integrated photovoltaic panels and building integrated solar thermal panels are not required to meet the minimum requirements for solar reflectance, thermal emittance, or SRI.

B. Roof Insulation. Roofs shall have an overall assembly U-factor no greater than the applicable value in ., and where required by Section 110.8 and 120.7(a)3, insulation shall be placed in direct contact with a roof or drywall ceiling.

2. Exterior walls. Exterior walls shall have an overall assembly U-factor no greater than the applicable value in .

3. Demising walls. Demising walls shall meet the requirements of Section 120.7(b)7. Vertical windows in demising walls between conditioned and unconditioned spaces shall have an area-weighted average U-factor no greater than the applicable value in .

4. Exterior floors and soffits. Exterior floors and soffits shall have an overall assembly U-factor no greater than the applicable value in .

5. Exterior windows. Vertical windows in exterior walls shall:

A. Percent window area shall be limited in accordance with the applicable requirements of i and ii below:

i. a west-facing area no greater than 40 percent of the gross west-facing exterior wall area, or 6 feet times the west-facing display perimeter, whichever is greater; and

ii. a total area no greater than 40 percent of the gross exterior wall area, or 6 feet times the display perimeter, whichever is greater; and

Note: Demising walls are not exterior walls, and therefore demising wall area is not part of the gross exterior wall area or display perimeter, and windows in demising walls are not part of the window area.

Exception to Section 140.3(a)5A: Conditioned greenhouses. The requirements of Section 120.6(h)3 apply.

B. Have an area-weighted average U-factor no greater than the applicable value in .

Exception 1 to Section 140.3(a)5B: Conditioned greenhouses. The requirements of Section 120.6(h)3 apply.

Exception 2 to Section 140.3(a)5B: For vertical windows containing chromogenic type glazing:

i. The lower-rated labeled U-factor shall be used with automatic controls to modulate the amount of heat flow into the space in multiple steps in response to daylight levels or solar intensity; and

ii. Chromogenic glazing shall be considered separately from other glazing; and

iii. Area-weighted averaging with other glazing that is not chromogenic shall not be permitted.

C. Have an area-weighted average relative solar heat gain coefficient, RSHGC, excluding the effects of interior shading, no greater than the applicable value in .

For purposes of this paragraph, the relative solar heat gain coefficient, RSHGC, of a vertical window is:

i. The solar heat gain coefficient of the windows; or

ii. Relative solar heat gain coefficient is calculated using Equation 140.3-A, if the window has an overhang or exterior horizontal slats that extend beyond each side of the window jamb by a distance equal to the overhang’s horizontal projection.

Exception 1 to Section 140.3(a)5C: An area-weighted average relative solar heat gain coefficient of 0.56 or less shall be used for windows:

a. That are in the first story of exterior walls that form a display perimeter; and
b. For which codes restrict the use of overhangs to shade the windows.

Exception 2 to Section 140.3(a)5C: For vertical glazing containing chromogenic type glazing:

i. the lower-rated labeled RSHGC shall be used with automatic controls to modulate the amount of heat flow into the space in multiple steps in response to daylight levels or solar intensity; and
ii. chromogenic glazing shall be considered separately from other glazing; and
iii. area-weighted averaging with other glazing that is not chromogenic shall not be permitted.

Exception 3 to Section 140.3(a)5C: Conditioned greenhouses. The requirements of Section 120.6(h)3 apply.

Note: Demising walls are not exterior walls, and therefore windows in demising walls are not subject to SHGC requirements.

D. Have an area-weighted average Visible Transmittance (VT) no less than the applicable value in , or Equation 140.3-B, as applicable.

Exception 1 to Section 140.3(a)5D: When the window’s primary and secondary sidelit daylit zones are completely overlapped by one or more skylit daylit zones, then the window need not comply with Section 140.3(a)5D.

Exception 2 to Section 140.3(a)5D: If the window’s VT is not within the scope of NFRC 200, or ASTM E972, then the VT shall be calculated according to Reference Nonresidential Appendix NA6.

Exception 3 to Section 140.3(a)5D: For vertical glazing containing chromogenic type glazing:
i. The higher-rated labeled VT shall be used with automatic controls to modulate the amount of light transmitted into the space in multiple steps in response to daylight levels or solar intensity; and
ii. Chromogenic glazing shall be considered separately from other glazing; and
iii. Area-weighted averaging with other glazing that is not chromogenic shall not be permitted.

Exception 4 to Section 140.3(a)5D: Conditioned greenhouses. The requirements of Section 120.6(h)4 apply.

Note: Demising walls are not exterior walls, and therefore windows in demising walls are not subject to VT requirements.

EQUATION 140.3-A RELATIVE SOLAR HEAT GAIN COEFFICIENT, RSHGC

RSHGC = SHGC × [1 + a × (2.72^-PF – 1) × (sin(b × Az) + c]

where:

Feature	a	b	c
Overhang	0.150	0.008727	5.67
Exterior Horizontal Slat	0.144	0.008727	5.13

RSHGC = Relative Solar Heat Gain Coefficient.
SHGC = Solar Heat Gain Coefficient of the vertical fenestration.
Az = Azimuth of the vertical fenestration in degrees.
PF = Projection factor as calculated by Equation 140.3-C.

EQUATION 140.3-B VERTICAL FENESTRATION MINIMUM VT

VT ≥ 0.11/ WWR

where:

WWR = Window Wall Ratio, the ratio of (i) the total window area of the entire building to (ii) the total gross exterior wall area of the entire building. If the WWR is greater than 0.40, then 0.40 shall be used as the value for WWR in Equation 140.3-B.

VT = Visible Transmittance of framed window.

6. Skylights. Skylights shall:

A. Have an area no greater than 5 percent of the gross exterior roof area Skylight Roof Ratio (SRR); and

Exception 1 to Section 140.3(a)6A: Buildings with atria over 55 feet high shall have a skylight area no greater than 10 percent of the gross exterior roof area.

Exception 2 to Section 140.3(a)6A: Conditioned greenhouses. The requirements of Section 120.6(h)3 apply.

B. Have an area-weighted performance rating U-factor no greater than the applicable value in .

Exception 1 to Section 140.3(a)6B: For skylights containing chromogenic type glazing:
i. The lower-rated labeled U-factor shall be used with automatic controls to modulate the amount of heat flow into the space in multiple steps in response to daylight levels or solar intensity; and
ii. chromogenic glazing shall be considered separately from other glazing; and
iii. area-weighted averaging with other glazing that is not chromogenic shall not be permitted.

Exception 2 to Section 140.3(a)6B: Conditioned greenhouses. The requirements of Section 120.6(h)3 apply.

C. Have an area-weighted performance rating solar heat gain coefficient no greater than the applicable value in .

Exception 1 to Section 140.3(a)6C: For skylights containing chromogenic type glazing:
i. the lower-rated labeled SHGC shall be used to demonstrate compliance with this section; and
ii. chromogenic glazing shall be considered separately from other glazing; and
iii. area-weighted averaging with other glazing that is not chromogenic shall not be permitted.

Exception 2 to Section 140.3(a)6C: Conditioned greenhouses. The requirements of Section 120.6(h)3 apply.

D. Have an area-weighted performance rating VT no less than the applicable value in ; and

Exception 1 to Section 140.3(a)6D: For skylights containing chromogenic type glazing:
i. the higher-rated labeled VT shall be used with automatic controls to modulate the amount of light transmitted into the space in multiple steps in response to daylight levels or solar intensity and;
ii. chromogenic glazing shall be considered separately from other glazing; and
iii. area-weighted averaging with other glazing that is not chromogenic shall not be permitted.

Exception 2 to Section 140.3(a)6D: Conditioned greenhouses. The requirements of Section 120.6(h)3 apply.

E. Have a glazing material or diffuser that has a measured haze value greater than 90 percent, determined according to ASTM D1003 or other test method approved by the Energy Commission.

Exception 1 to Section 140.3(a)6E: Skylights designed and installed to exclude direct sunlight entering the occupied space by the use of fixed or automated baffles or the geometry of the skylight and light well.

Exception 2 to Section 140.3(a)6E: Conditioned greenhouses. The requirements of Section 120.6(h)3 apply.

7. Exterior doors. All exterior doors that separate conditioned space from unconditioned space or from ambient air shall have a U-factor not greater than the applicable value in . Doors that are more than one-quarter glass in area are considered glazed doors.

8. Relocatable public school buildings. In complying with Sections 140.3(a)1A to 7 shall meet the following:

A. Relocatable public school buildings shall comply with Table 140.3-B for a specific climate zone when the manufacturer or builder of the relocatable public school building certifies that the building is intended for use only in a specific climate zone; or

B. Relocatable public school buildings shall comply with Table 140.3-D for any climate zone when the manufacturer or builder of the relocatable public school building certifies that the building is intended for use in any climate zone; and

C. The manufacturer or builder of a relocatable public school building shall certify that components of the building comply with requirements of this section by:

i. The placement of two (2) metal identification labels on the building, one mechanically fastened and visible from the exterior and the other mechanically fastened to the interior frame above the ceiling at the end of the module, both labels stating (in addition to any other information by the Division of the State Architect or other law) "Complies with Title 24, Part 6 for all climate zones”; and

ii. Identification of the location of the two labels on the plans submitted to the enforcing agency.

9. Air barrier. To meet the requirement of Table 140.3-B, all buildings shall have a continuous air barrier that is designed and constructed to control air leakage into, and out of, the building’s conditioned space.

Exception to Section 140.3(a)9: Relocatable public school buildings.

A. Design. Construction documents shall include air barrier boundaries, interconnections and penetrations, and associated square foot calculations for all sides of the air barrier.

B. Acceptable materials and assemblies. The air barrier shall be sealed at all joints for its entire length and shall be composed of:

i. Materials that have an air permeance not exceeding 0.004 cfm/ft², under a pressure differential of 0.3 in. of water (1.57 psf) (0.02 L/(sec-m²) at 75 Pa), when tested in accordance with ASTM E2178; or

Exception to Section 140.3(a)9Bi: Materials in Table 140.3-A shall be deemed to comply with Section 140.3(a)9B provided that all joints are sealed and all of the materials are installed as air barriers in accordance with the manufacturer's instructions.

ii. Assemblies of materials and components that have an average air leakage not exceeding 0.04 cfm/ft², under a pressure differential of 0.3 in. of water (1.57 psf) (0.2 L/m² at 75 pa), when tested in accordance with ASTM E2357, ASTM E1677, ASTM E1680, or ASTM E283.

Exception to Section 140.3(a)9Bii: The following materials shall be deemed to comply with Section 140.3(a)9B if all joints are sealed and all of the materials are installed as air barriers in accordance with the manufacturer's instructions:
a.    Concrete masonry walls that have at least two coatings of paint or at least two coatings of sealer coating.
b.    Concrete masonry walls with integral rigid board insulation.
c.     Structurally insulated panels.
d.    Portland cement or Portland sand parge, or stucco, or a gypsum plaster, each with minimum 1/2 inch thickness.

C. Verification. Verification of the installed air barrier may be performed.

i. If verification is performed the entire building shall meet one of the following requirements:

a. An air leakage rate not exceeding 0.40 cfm/ft² at a pressure differential of 0.3 in. of water (1.57 psf) (2.0 L/m² at 75 Pa), when the entire building is tested, after completion of construction, in accordance with NA5, or another test method approved by the Commission; or

b. For buildings that have more than 50,000 ft² of conditioned floor area, a sectional test method of co-pressurizing representative test floors and taking data from the specific floors to achieve the requirement in Section 140.3(a)9Ci when following the procedures in Sections NA5.2 to NA5.7. Representative test floors must meet the following conditions:

I. The entire floor area of all stories that have any spaces directly under a roof.
II. The entire floor area of all stories that have a building entrance or loading dock.
III. Representative above grade wall sections of the building totaling at least 25 percent of the wall area enclosing the remaining conditioned space. Floor areas in parts a and b above shall not be included in the 25 percent.

ii. If the air leakage requirements of either Section 140.3(a)9Cia or 140.3(a)9Cib are not met, a visual inspection and diagnostic evaluation shall be completed in accordance with NA5.7, all observed leaks shall be sealed where such sealing can be made without destruction of existing building components, and buildings where the tested leakage rate exceeded 0.6 cfm/ft² of building shell area at 75 Pa have been retested to confirm leakage is below 0.6 cfm/ft² of building shell at 75 Pa.

TABLE 140.3-A MATERIALS DEEMED TO COMPLY WITH SECTION 140.3(a)9B

MATERIALS	MINIMUM THICKNESS
Plywood	Minimum 3/8inches thickness
Oriented strand board	Minimum 3/8 inches thickness
Extruded polystyrene insulation board	Minimum 1/2 inches thickness
Foil-backed polyisocyanurate insulation board	Minimum 1/2 inches thickness
Closed cell spray foam with a minimum density of 2.0 pcf	Minimum 2 inches thickness
Open cell spray foam with a density no less than 0.4 pcf and no greater than 1.5 pcf	Minimum 5-1/2 inches thickness
Exterior and interior gypsum board	Minimum 1/2 inches thickness
Cement board	Minimum 1/2 inches thickness
Built up roofing membrane	No minimum thickness
Modified bituminous roof membrane	No minimum thickness
Fully adhered single-ply roof membrane	No minimum thickness
A Portland cement or Portland sand parge, or a gypsum plaster	Each with Minimum 5/8 inches thickness
Cast-in-place concrete, or precast concrete	No minimum thickness
Fully grouted concrete block masonry	No minimum thickness
Sheet steel or sheet aluminum	No minimum thickness

TABLE 140.3-B – PRESCRIPTIVE ENVELOPE CRITERIA FOR NONRESIDENTIAL BUILDINGS (INCLUDING RELOCATABLE PUBLIC SCHOOL BUILDINGS (WHERE MANUFACTURER CERTIFIES USE ONLY IN SPECIFIC CLIMATE ZONE; NOT INCLUDING HIGH-RISE RESIDENTIAL BUILDINGS AND GUEST ROOMS OF HOTEL/MOTEL BUILDINGS)

Envelope Feature	CZ 1	CZ 2	CZ 3	CZ 4	CZ 5	CZ 6	CZ 7	CZ 8	CZ 9	CZ 10	CZ 11	CZ 12	CZ 13	CZ 14	CZ 15	CZ 16
Roofs and Ceilings - Metal Building Max U-Factor	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038	0.038
Roofs and Ceilings - Wood Framed and Other Max U-Factor	0.028	0.028	0.028	0.028	0.028	0.047	0.047	0.047	0.028	0.028	0.028	0.028	0.028	0.028	0.028	0.028
Walls - Metal Building Max U-Factor	0.098	0.053	0.098	0.053	0.053	0.098	0.098	0.053	0.053	0.053	0.053	0.053	0.053	0.053	0.050	0.053
Walls - Metal-framed Max U-Factor	0.060	0.055	0.071	0.055	0.055	0.060	0.060	0.055	0.055	0.055	0.055	0.055	0.055	0.055	0.055	0.055
Walls - Mass, Light¹ Max U-Factor	0.170	0.138	0.227	0.196	0.364	0.364	0.364	0.364	0.364	0.138	0.138	0.138	0.138	0.138	0.138	0.138
Walls - Mass, Heavy² Max U-Factor	0.211	0.650	0.650	0.650	0.650	0.690	0.690	0.690	0.690	0.650	0.160	0.211	0.184	0.160	0.160	0.153
Walls - Wood-framed and Other Max U-Factor	0.078	0.053	0.102	0.053	0.095	0.102	0.102	0.095	0.053	0.053	0.042	0.053	0.053	0.053	0.038	0.053
Floors and Soffits - Raised Mass Max U-Factor	0.092	0.092	0.269	0.269	0.269	0.269	0.269	0.269	0.269	0.269	0.092	0.092	0.092	0.092	0.092	0.058
Floors and Soffits - Other Max U-Factor	0.048	0.039	0.071	0.071	0.071	0.071	0.071	0.071	0.071	0.071	0.039	0.071	0.071	0.039	0.039	0.039
Roofing Products - Low Sloped Aged Solar Reflectance	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63
Roofing Products - Low-Sloped Thermal Emittance	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75
Roofing Products - Steep-Sloped Aged Solar Reflectance	0.20	0.25	0.20	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25
Roofing Products - Steep-Sloped Thermal Emittance	0.75	0.80	0.75	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80
Air Barrier	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ

CONTINUED: TABLE 140.3-B – PRESCRIPTIVE ENVELOPE CRITERIA FOR NONRESIDENTIAL BUILDINGS (INCLUDING RELOCATABLE PUBLIC SCHOOL BUILDINGS WHERE MANUFACTURER CERTIFIES USE ONLY IN SPECIFIC CLIMATE ZONE; NOT INCLUDING HIGH-RISE RESIDENTIAL BUILDINGS AND GUEST ROOMS OF HOTEL/MOTEL BUILDINGS)

Fenestration – Vertical (All Climate Zones) (Area-Weighted Performance Rating)	CZ 1	CZ 2	CZ3	CZ 4	CZ 5	CZ 6	CZ 7	CZ 8	CZ 9	CZ 10	CZ 11	CZ 12	CZ 13	CZ 14	CZ 15	CZ 16
Fixed Window (Max U-factor)	0.36	0.36	0.36	0.36	0.36	0.36	0.36	0.36	0.34	0.36	0.34	0.34	0.34	0.34	0.34	0.36
Fixed Window (Max RSHGC)	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.22	0.25	0.22	0.22	0.22	0.22	0.22	0.25
Fixed Window (Min VT)	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42	0.42
Curtain Wall or Storefront (Max U-factor)	0.38	0.41	0.41	0.41	0.41	0.41	0.38	0.41	0.41	0.41	0.41	0.41	0.41	0.41	0.41	0.41
Curtain Wall or Storefront (Max RSHGC)	0.25	0.26	0.26	0.26	0.26	0.26	0.25	0.26	0.26	0.26	0.26	0.26	0.26	0.26	0.26	0.26
Curtain Wall or Storefront (Min VT)	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46
Operable Window (Max U-factor)	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46	0.46
Operable Window (Max RSHGC)	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22
Operable Window (Min VT)	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32	0.32
Glazed Doors (Max U-factor)	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45	0.45
Glazed Doors (Max RSHGC)	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23	0.23
Glazed Doors (Min VT)	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17
Fenestration (Max WWR %)	40%	40%	40%	40%	40%	40%	40%	40%	40%	40%	40%	40%	40%	40%	40%	40%
Exterior Doors - Non-Swinging Maximum U-Factor	0.50	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	0.50
Exterior Doors – Swinging Maximum U-Factor	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70

Fenestration - Skylights (all Climate Zones) (Area-weighted Performance Rating)	Glass Curb Mounted	Glass Deck Mounted	Plastic Curb Mounted	Tubular Daylighting Devices (TDDs)
Max U-factor	0.58	0.46	0.88	0.88
Max SHGC	0.25	0.25	NR	NR
Min VT (Min VTannual for TDDs)	0.49	0.49	0.64	0.38
Maximum SRR%	5%	5%	5%	5%

TABLE 140.3-C – PRESCRIPTIVE ENVELOPE CRITERIA FOR GUEST ROOMS OF HOTEL/MOTEL BUILDINGS

Envelope Feature	Climate Zones
Envelope Feature	CZ 1	CZ 2	CZ 3	CZ 4	CZ 5	CZ 6	CZ 7	CZ 8	CZ 9	CZ 10	CZ 11	CZ 12	CZ 13	CZ 14	CZ 15	CZ 16
Roofs and Ceilings - Metal Building Max U-Factor	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041	0.041
Roofs and Ceilings - Wood Framed and Other Max U-Factor	0.028	0.028	0.034	0.028	0.034	0.034	0.039	0.028	0.028	0.028	0.028	0.028	0.028	0.028	0.028	0.028
Walls - Metal Building Max U-Factor	0.061	0.061	0.061	0.061	0.061	0.061	0.061	0.061	0.061	0.061	0.057	0.057	0.057	0.057	0.057	0.057
Walls - Metal-framed Max U-Factor	0.069	0.069	0.069	0.069	0.069	0.069	0.105	0.069	0.069	0.069	0.069	0.069	0.069	0.069	0.048	0.069
Walls - Mass, Light¹ Max U-Factor	0.170	0.170	0.170	0.170	0.170	0.227	0.227	0.227	0.196	0.170	0.170	0.170	0.170	0.170	0.170	0.170
Walls - Mass, Heavy¹ Max U-Factor	0.160	0.160	0.160	0.184	0.211	0.690	0.690	0.690	0.690	0.690	0.184	0.253	0.211	0.184	0.184	0.160
Walls - Wood-framed and Other Max U-Factor	0.059	0.059	0.059	0.059	0.059	0.059	0.059	0.059	0.059	0.059	0.042	0.059	0.059	0.042	0.042	0.042
Floors and Soffits - Raised Mass Max U-Factor	0.045	0.045	0.058	0.058	0.058	0.069	0.092	0.092	0.092	0.069	0.058	0.058	0.058	0.045	0.058	0.037
Floors and Soffits - Other Max U-Factor	0.034	0.034	0.039	0.039	0.039	0.039	0.071	0.039	0.039	0.039	0.039	0.039	0.039	0.034	0.039	0.034
Low Sloped Roofing Products Aged Solar Reflectance	NR	NR	NR	NR	NR	NR	NR	NR	0.55	0.55	0.55	NR	0.55	0.55	0.55	NR
Low Sloped Roofing Products Thermal Emittance	NR	NR	NR	NR	NR	NR	NR	NR	0.75	0.75	0.75	NR	0.75	0.75	0.75	NR
Steep Sloped Roofing Products Aged Solar Reflectance	NR	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	NR
Steep Sloped Roofing Products Thermal Emittance	NR	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	0.75	NR
Air Barrier	REQ	REQ	REQ	REQ	REQ	REQ	NR	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ	REQ
Non-Swinging Exterior Doors Max U-Factor	0.50	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	1.45	0.50
Swinging Exterior Doors Max U-Factor	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70	0.70

CONTINUED: TABLE 140.3-C – PRESCRIPTIVE ENVELOPE CRITERIA FOR GUEST ROOMS OF HOTEL/MOTEL BUILDINGS

Fenestration – Vertical (All Climate Zones) (Area-Weighted Performance Rating)	Fixed Window	Operable Window	Curtainwall and Storefront	Glazed Doors*
Max U-factor	0.36	0.46	0.41	0.45
Max RSHGC	0.25	0.22	0.26	0.23
Min VT	0.42	0.32	0.46	0.17
Maximum WWR%	40%	40%	40%	40%

CONTINUED: TABLE 140.3-C – PRESCRIPTIVE ENVELOPE CRITERIA FOR GUEST ROOMS OF HOTEL/MOTEL BUILDINGS

Fenestration - Skylights (All Climate Zones) (Area-Weighted Performance Rating)	Glass Curb Mounted	Glass Deck Mounted	Plastic Curb Mounted
Max U-factor	0.58	0.46	0.88
Max SHGC	0.25	0.25	NR
Min VT	0.49	0.49	0.64
Maximum SRR%	5%	5%	5%

Notes:

b. As defined in Section 100.1, light mass walls are walls with a heat capacity of at least 7.0 Btu/ft²-°F and less than 15.0 Btu/ft²-°F. Heavy mass walls are walls with a heat capacity of at least 15.0 Btu/ft²-°F.

c. Glazed Doors applies to both site-built and to factory-assembled glazed doors.

TABLE 140.3-D PRESCRIPTIVE ENVELOPE CRITERIA FOR RELOCATABLE PUBLIC SCHOOL BUILDINGS FOR USE IN ALL CLIMATE ZONES

Envelope Feature	Criteria	Value
Roofs and Ceilings - Metal Buildings	Maximum U-factor	0.041
Roofs and Ceilings - Non-Metal Buildings	Maximum U-factor	0.034
Walls - Wood frame buildings	Maximum U-factor	0.042
Walls - Metal frame buildings	Maximum U-factor	0.057
Walls - Metal buildings	Maximum U-factor	0.052
Walls - Mass/7.05 HC	Maximum U-factor	0.170
Walls - All Other Walls	Maximum U-factor	0.059
Floors and Soffits	Maximum U-factor	0.048
Roofing Products - Low-Sloped	Aged Solar Reflectance	0.63
Roofing Products - Low-Sloped	Thermal Emittance	0.75
Roofing Products - Steep-Sloped	Aged Solar Reflectance	0.25
Roofing Products - Steep-Sloped	Thermal Emittance	0.80
Fenestration - Windows	Maximum U-factor	0.47
Fenestration - Windows	Maximum SHGC	0.26
Fenestration - Glazed Doors (Site-Built and Factory Assembled)	Maximum U-factor	0.45
Fenestration - Glazed Doors (Site-Built and Factory Assembled)	Maximum SHGC	0.23
Fenestration - Skylights Glass with Curb	Maximum U-factor	0.99
Fenestration - Skylights Glass with Curb	Maximum SHGC	0.57
Fenestration - Skylights Glass without Curb	Maximum U-factor	0.87
Fenestration -Skylights - Glass Type	0-2% SRR Maximum SHGC	0.46
Fenestration -Skylights - Glass Type	2.1-5% SRR Maximum SHGC	0.36
Fenestration -Skylights - Plastic Type	0-2% SRR Maximum SHGC	0.69
Fenestration -Skylights - Plastic Type	2.1-5% SRR Maximum SHGC	0.57
Exterior Doors - Non-Swinging doors	Maximum U-factor	0.50

(b) Reserved

(c) Minimum daylighting requirement for large enclosed spaces. In climate zones 2 through 15, conditioned enclosed spaces, and unconditioned enclosed spaces that are greater than 5,000 square feet and that are directly under a roof with ceiling heights greater than 15 feet, shall meet the following requirements:



1. A combined total of at least 75 percent of the floor area, as determined in building floor plan (drawings) view, shall be within one or more of the following:

A. Primary sidelit daylit zone in accordance with Section 130.1(d), or

B. The total floor area in the space within a horizontal distance of 0.7 times the average ceiling height from the edge of rough opening of skylights.

2. All skylit daylit zones and primary sidelit daylit zones shall be shown on building plans.

3. General lighting in daylit zones shall be controlled in accordance with Section 130.1(d).

4. The total skylight area is at least 3 percent of the total floor area in the space within a horizontal distance of 0.7 times the average ceiling height from the edge of rough opening of skylights or the product of the total skylight area and the average skylight visible transmittance is no less than 1.5 percent of the total floor area in the space within a horizontal distance of 0.7 times the average ceiling height from the edge of rough opening of skylights.

5. All skylights shall have a glazing material or diffuser that has a measured haze value greater than 90 percent, tested according to ASTM D1003 (notwithstanding its scope) or other test method approved by the Commission.

6. Skylights for conditioned and unconditioned spaces shall have an area-weighted average Visible Transmittance (VT) no less than the applicable value required by Section 140.3(a)6D.

Exception 1 to Section 140.3(c): Auditoriums, churches, movie theaters, museums and refrigerated warehouses.

Exception 2 to Section 140.3(c): In buildings with unfinished interiors, future enclosed spaces for which there are plans to have:

A floor area of less than or equal to 5,000 square feet, or
Ceiling heights of less than or equal to 15 feet.

This exception shall not be used for S-1 or S-2 (storage), or for F-1 or F-2 (factory) occupancies.

Exception 3 to Section 140.3(c): Enclosed spaces having a designed general lighting system with a lighting power density less than 0.5 watts per square foot.

Exception 4 to Section 140.3(c): Enclosed spaces where it is documented that permanent architectural features of the building, existing structures or natural objects block direct beam sunlight on at least half of the roof over the enclosed space for more than 1500 daytime hours per year between 8 a.m. and 4 p.m.

(d) Daylighting Design Power Adjustment Factors (PAFs).To qualify for a Power Adjustment Factor (PAF) as specified in Section 140.6(a)2L, daylighting devices shall meet the following requirements:

1. Clerestory fenestration. To qualify for a PAF, clerestory fenestration shall meet the following requirements:

A. Shall be installed on east, west, or south-facing façades.

B. Shall have a head height that is at least 10 feet above the finished floor.

C. Shall have a glazing height that is greater than or equal to 10 percent of the head height.

D. If operable shading is installed on the clerestory fenestration, then the clerestory fenestration shading shall be controlled separately from shading serving other vertical fenestration.

2. Interior and exterior horizontal slats. To qualify for a PAF, horizontal slats shall meet the following requirements:

A. Shall be installed adjacent to vertical fenestration on east or west-facing facades with Window Wall Ratios between 20 and 30 percent.

B. Exterior horizontal slats shall be level or sloped downwards from fenestration. Interior horizontal slats shall be level or sloped upwards from fenestration.

C. Shall have a projection factor as specified in Table 140.3-E. The projection factor is calculated using Equation 140.3-C.

D. Shall have a minimum distance factor of 0.3. The distance factor is calculated using Equation 140.3-C.

Exception to Section 140.3(d)2D: Where it is documented that existing adjacent structures or natural objects within view of the vertical fenestration block direct sunlight onto the vertical fenestration between 8 a.m. and 5 p.m. for less than 500 daytime hours per year.

E. Shall have a minimum Visible Reflectance of 0.50 when tested as specified in ASTM E903.

F. Shall be opaque.

Exception to Section 140.3(d)2F: Horizontal slats with a Visible Transmittance of 0.03 or less when tested as specified in ASTM E1175.

G. Shall be permanently mounted and not adjustable.

H. Shall extend the entire height of the vertical fenestration and beyond each side of the window jamb by a distance equal to or greater than their horizontal projection.

Exception to Section 140.3(d)2H: Where the slats are located entirely within the vertical fenestration’s rough opening, or a fin is located at the window jambs and extends vertically the entire height of the window jamb and extends horizontally the entire depth of the projection.

I. Shall be shown on the plans with the dimensions for the slat projection and slat spacing as specified in Equation 140.3-C.

J. Shall have a conspicuous factory installed label permanently affixed and prominently located on an attachment point of the device to the building envelope, stating the following: “NOTICE: Removal of this device will require re-submittal of compliance documentation to the enforcement agency responsible for compliance with California Title 24, Part 6”.

3. Interior and exterior light shelves. To qualify for a PAF, light shelves shall meet the following requirements:

A. Where there is vertical fenestration area below the light shelf, both interior and exterior light shelves shall be installed.

B. Shall be installed adjacent to clerestory fenestration on south-facing façades with Window Wall Ratios greater than 30 percent. The head height of the light shelves shall be no more than one foot below the finished ceiling. The clerestory fenestration shall meet the requirements of Section 140.3(d)1.

C. Exterior light shelves shall be level or sloped downwards from fenestration. Interior light shelves shall be level or sloped upwards from fenestration.

D. Shall have a projection factor of the applicable value as specified in Table 140.3-E. The light shelf projection factor is calculated using Equation 140.3-C.

E. Shall have a minimum Distance Factor of 0.3. The distance factor is calculated using Equation 140.3-C.

Exception to Section 140.3(d)3E: Where it is documented that existing adjacent structures or natural objects within view of the vertical fenestration block direct sunlight onto the vertical fenestration between 8 a.m. and 5 p.m. for less than 750 daytime hours per year.

F. Shall have a top surface with a minimum Visible Reflectance of 0.50 when tested as specified in ASTM E903.

Exception to Section 140.3(d)3F: Where an exterior light shelf is installed greater than two feet below the clerestory sill.

G. Shall extend beyond each side of the window jamb by a distance equal to or greater than their horizontal projection.

H. Shall be shown on the plans with the dimensions for the light shelf projection and light shelf spacing as specified in Equation 140.3-C.

TABLE 140.3-E Daylighting Devices

Daylighting Device	Orientation of the Vertical Fenestration	Projection Factor
Horizontal Slats	East or West	2.0 to 3.0
Interior Light Shelf	South	1.0 to 2.0
Exterior Light Shelf	South	0.25 to 1.25

EQUATION 140.3-C PROJECTION AND DISTANCE FACTOR CALCULATION

Projection Factor = Projection / Spacing

Distance Factor – D / (HAS x Projection Factor)

Where:

Projection = The horizontal distance between the base edge and the projected edge of the overhang, slat, or light shelf..

Spacing = For overhangs, the vertical distance between the projected edge of the overhang and sill of the vertical fenestration below it.

For horizontal slats, the vertical distance between the projected edge of a slat to the base edge of the slat below it.

For interior light shelves, the vertical distance between the projected edge of the light shelf and head of the clerestory fenestration above it.

For exterior light shelves, the vertical distance between the projected edge of the light shelf and sill of the vertical fenestration below it.

D = Distance between the existing structure or nature object and the fenestration

HAS = Height difference between the top of the existing structure or nature object and the bottom of the fenestration

NOTE: The base edge is the edge of an overhang, slat, or light shelf that is adjacent to the vertical fenestration. The projected edge is the opposite edge from the base edge.

Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8, and 25943, Public Resources Code.

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