SECTION 150.0 – MANDATORY FEATURES AND DEVICES

Low-rise residential buildings shall comply with the applicable requirements of Sections 150(a) through 150.0(r).

NOTE:  The requirements of Sections 150.0(a) through 150.0(r) apply to newly constructed buildings. Sections 150.2(a) and 150.2(b) specify which requirements of Sections 150.0(a) through 150.0(r) also apply to additions or alterations.

(a)        Ceiling and Rafter Roof Insulation.

The opaque portions of ceilings and roofs separating conditioned spaces from unconditioned spaces or ambient air shall meet the requirements of Items 1 through 3 below:

1.   Shall be insulated to achieve a weighted average U-factor not exceeding U-0.043 or shall be insulated between wood-framing members with insulation resulting in an installed thermal resistance of R-22 or greater for the insulation alone.  For vented attics, the mandatory insulation shall be installed at the ceiling level; for unvented attics, the mandatory insulation shall be placed at either ceiling or roof level; and

EXCEPTION to Section 150.0(a)1: Ceilings and rafter roofs in an alteration shall be insulated to achieve a weighted average U-factor not exceeding 0.054 or shall be insulated between wood-framing members with insulation resulting in an installed thermal resistance of R-19 or greater

2.   Attic access doors shall have permanently attached insulation using adhesive or mechanical fasteners. The attic access shall be gasketed to prevent air leakage; and

3.   Insulation shall be installed in direct contact with a continuous roof or ceiling which is sealed to limit infiltration and exfiltration as specified in Section 110.7, including but not limited to placing insulation either above or below the roof deck or on top of a drywall ceiling.

(b)       Loose-fill Insulation.

When loose-fill insulation is installed, the minimum installed weight per square foot shall conform with the insulation manufacturer's installed design weight per square foot at the manufacturer's labeled R-value.

(c)        Wall Insulation.

Opaque portions of above grade walls separating conditioned spaces from unconditioned spaces or ambient air shall meet the following requirements:

1.   2x4 inch framing, shall have an overall assembly U-factor not exceeding U-0.102

EXCEPTION to Section 150.0(c)1: Existing walls already insulated to a U-factor not exceeding U-0.110 or already insulated between framing members with insulation having an installed thermal resistance of R-11 or greater.

2.   2x6 inch or greater, framing shall have an overall assembly U-factor not exceeding U-0.071.

3.   Opaque non-framed assemblies shall have an overall assembly U-factor not exceeding U-0.102.

4.   Bay or Bow Window roofs and floors shall be insulated to meet the wall insulation requirements of TABLE 150.1-A or B.

5.   Masonry walls shall be insulated to meet the wall insulation requirements of TABLE 150.1-A or B.

6.   In wood framed assemblies, compliance with U-factors may be demonstrated by installing wall insulation with an R-value of 13 in 2x4 assemblies, and 20 in 2x6 assemblies.

(d)       Raised-floor Insulation.

Raised floors separating conditioned space from unconditioned space or ambient air shall have an overall assembly U-factor not exceeding U-0.037.  In a wood framed assembly, compliance with the U-factor may be demonstrated by installing insulation with an R-value of 19 or greater.

EXCEPTION to Section 150.0(d): A building with a controlled ventilation or unvented crawl space may omit raised floor insulation if all of the following are met:

A.   The foundation walls are insulated to meet the wall insulation minimums as shown in TABLE 150.1-A or B; and

B.   A Class I or Class II vapor retarder is placed over the entire floor of the crawl space; and

C.   Vents between the crawl space and outside air are fitted with automatically operated louvers that are temperature actuated; and

D.   The requirements in Reference Residential Appendix RA4.5.1.

(e)        Installation of Fireplaces, Decorative Gas Appliances and Gas Logs.

If a masonry or factory-built fireplace is installed, it shall comply with Section 110.5, Section 4.503 of Part 11, and shall have the following:

1.   Closeable metal or glass doors covering the entire opening of the firebox; and

2.   A combustion air intake to draw air from the outside of the building, which is at least 6 square inches in area and is equipped with a readily accessible, operable, and tight-fitting damper or combustion-air control device; and

EXCEPTION to Section 150.0(e)1B: An outside combustion-air intake is not required if the fireplace will be installed over concrete slab flooring and the fireplace will not be located on an exterior wall.

3.   A flue damper with a readily accessible control.

EXCEPTION to Section 150.0(e)1C: When a gas log, log lighter, or decorative gas appliance is installed in a fireplace, the flue damper shall be blocked open if required by the CMC or the manufacturer's installation instructions.

(f)        Slab Edge Insulation.

Material used for slab edge insulation shall meet the following minimum specifications:

1.   Water absorption rate for the insulation material alone without facings no greater than 0.3 percent when tested in accordance with Test Method A – 24-Hour-Immersion of ASTM C272.

2.   Water vapor permeance no greater than 2.0 perm/inch when tested in accordance with ASTM E96.

3.   Concrete slab perimeter insulation shall be protected from physical damage and ultraviolet light deterioration.

4.   Insulation for a heated slab floor shall meet the requirements of Section 110.8(g).

(g)       Vapor Retarder.

1.   In Climate Zones 1-16, the earth floor of unvented crawl space shall be covered with a Class I or Class II vapor retarder. This requirement shall also apply to controlled ventilation crawl space for buildings complying with the Exception to Section 150.0(d).

2.   In Climate Zones 14 and 16, a Class I or Class II vapor retarder shall be installed on the conditioned space side of all insulation in all exterior walls, vented attics and unvented attics with air-permeable insulation.

(h)       Space-Conditioning Equipment.

1.   Building Cooling and Heating Loads. Building heating and cooling loads shall be determined using a method based on any one of the following:

A.   The ASHRAE Handbook, Equipment Volume, Applications Volume, and Fundamentals Volume; or

B.   The SMACNA Residential Comfort System Installation Standards Manual; or

C.   The ACCA Manual J.

The cooling and heating loads are two of the criteria that shall be used for equipment sizing and selection.

NOTE: Heating systems are required to have a minimum heating capacity adequate to meet the minimum requirements of the CBC. The furnace output capacity and other specifications are published in the Commission's directory of certified equipment or other directories approved by the Commission.

2.   Design conditions.

For the purpose of sizing the space-conditioning (HVAC) system, the indoor design temperatures shall be 68°F for heating and 75°F for cooling. Outdoor design conditions shall be selected from Reference Joint Appendix JA2, which is based on data from the ASHRAE Climatic Data for Region X. The outdoor design temperatures for heating shall be no lower than the Heating Winter Median of Extremes values. The outdoor design temperatures for cooling shall be no greater than the 1.0 percent Cooling Dry Bulb and Mean Coincident Wet Bulb values.

3.   Outdoor Condensing Units.

A.   Clearances. Installed air conditioner and heat pump outdoor condensing units shall have a clearance of at least five (5) feet (1.5 meters) from the outlet of any dryer vent.

B.   Liquid Line Drier.  Installed air conditioner and heat pump systems shall be equipped with liquid line filter driers if required, as specified by manufacturer’s instructions.

4.   Central Forced-Air Heating Furnaces.

A.   Temperature Rise. Central forced-air heating furnace installations shall be configured to operate in conformance with the furnace manufacturer's maximum inlet-to-outlet temperature rise specifications.

(i)         Thermostats.

All heating or cooling systems, including heat pumps, not controlled by a central energy management control system (EMCS) shall have a setback thermostat, as specified in Section 110.2(c).

(j)         Insulation for Piping and Tanks.

1.   Storage tank insulation.

Unfired hot water tanks, such as storage tanks and backup storage tanks for solar water-heating systems, shall be externally wrapped with insulation having an installed thermal resistance of R-12 or greater or have internal insulation of at least R-16 and a label on the exterior of the tank showing the insulation R-value.

2.   Water piping, solar water-heating system piping,  and space conditioning system line insulation thickness and conductivity.

Piping shall be insulated as follows:

A.   All domestic hot water piping shall be insulated as specified in Section 609.11 of the California Plumbing Code.  In ‘addition, the following piping conditions shall have a minimum insulation wall thickness of 1 inch or a minimum insulation R-value of 7.7:

i.    The first 5 feet (1.5 meters) of cold water pipes from the storage tank.

ii.    All hot water piping with a nominal diameter equal to or greater than 3/4 inch (19 millimeter) and less than 1 inch.

iii.   All hot water piping with a nominal diameter less than 3/4 inch that is:

a.   Associated with a domestic hot water recirculation system;

b.   From the heating source to the kitchen fixtures;

c.   From the heating source to a storage tank or between storage tanks; or

d.   Buried below grade.

B.   Piping for space conditioning systems, solar water-heating system collector loop, and distribution piping for steam and hydronic heating system, shall meet the requirements of Section 120.3(c).

EXCEPTION 1 to Section 150.0(j)2: Factory-installed piping within space-conditioning equipment certified under Section 110.1 or 110.2.

EXCEPTION 2 to Section 150.0(j)2: Piping that penetrates framing members shall not be required to have pipe insulation for the distance of the framing penetration. Piping that penetrates metal framing shall use grommets, plugs, wrapping or other insulating material to assure that no contact is made with the metal framing. Insulation shall abut securely against all framing members.

EXCEPTION 3 to Section 150.0(j)2: Piping installed in interior or exterior walls shall not be required to have pipe insulation if all of the requirements are met for compliance with Quality Insulation Installation (QII) as specified in the Reference Residential Appendix RA3.5.

EXCEPTION 4 to Section 150.0(j)2: Piping surrounded with a minimum of 1 inch of wall insulation, 2 inches of crawlspace insulation, or 4 inches of attic insulation, shall not be required to have pipe insulation.

3.   Insulation Protection.

Pipe insulation shall meet the insulation protection requirements of Section 120.3(b)

(k)        Residential Lighting.

1.   Luminaire Requirement

A.   Luminaire Efficacy.

All installed luminaires shall meet the requirements in TABLE 150.0-A.

B.   Blank Electrical Boxes.

The number of electrical boxes that are more than 5 feet above the finished floor and do not contain a luminaire or other device shall be no greater than the number of bedrooms. These electrical boxes must be served by a dimmer, vacancy sensor control, or fan speed control.

C.   Recessed Downlight Luminaires in Ceilings.

In ‘addition to complying with 150.0(k)1A, luminaires recessed into ceilings shall meet all of the following requirements:

i.    Be ‘listed, as defined in Section 100.1, for zero clearance insulation contact (IC) by Underwriters Laboratories or other nationally recognized testing/rating laboratory; and

ii.    Have a label that certifies the luminaire is airtight with air leakage less than 2.0 CFM at 75 Pascals when tested in accordance with ASTM E283. An exhaust fan housing shall not be required to be certified airtight; and

iii.   Be sealed with a gasket or caulk between the luminaire housing and ceiling, and have all air leak paths between conditioned and unconditioned spaces sealed with a gasket or caulk; and

iv.   For luminaires with hardwired ballasts or drivers, allow ballast or driver maintenance and replacement to be readily accessible to building occupants from below the ceiling without requiring the cutting of holes in the ceiling; and

v.   Shall not contain screw base sockets.

D.   Electronic Ballasts for Fluorescent Lamps.

Ballasts for fluorescent lamps rated 13 watts or greater shall be electronic and shall have an output frequency no less than 20 kHz.

E.   Night Lights, Step Lights and Path Lights.

Night lights, step lights and path lights shall not be required to comply with Table 150.0-A or be controlled by vacancy sensors provided they are rated to consume no more than 5 watts of power and emit no more than 150 lumens.

F.   Lighting Integral to Exhaust Fans.

Lighting integral to exhaust fans shall meet the applicable requirements of Section 150.0(k).

EXCEPTION to Section 150.0(k)1F: Lighting installed by the manufacturer in kitchen exhaust hoods.

G.   Screw based luminaires.

Screw based luminaires shall contain lamps that comply with Reference Joint Appendix JA8.

EXCEPTION to Section 150.0(k)1G: Luminaires with hard-wired ballasts for high intensity discharge lamps.

H.   Light Sources in Enclosed or Recessed Luminaires.

Lamps and other separable light sources that are not compliant with the JA8 elevated temperature requirements, including marking requirements, shall not be installed in enclosed or recessed luminaires.

I.    Light Sources in Drawers, Cabinets and Linen Closets.

Light sources internal to drawers, cabinetry or linen closets shall not be required to comply with Table 150.0-A or be controlled by vacancy sensors provided that they are rated to consume no more than 5 watts of power and emit no more than 150 lumens, and are equipped with controls that automatically turn the lighting off when the drawer, cabinet or linen closet is closed.

2.   Interior Lighting Switching Devices and Controls.

A.   All forward phase cut dimmers used with LED light sources shall comply with NEMA SSL 7A.

B.   Exhaust fans shall be controlled separately from lighting systems.

EXCEPTION to Section 150.0(k)2B: Lighting integral to an exhaust fan may be on the same control as the fan provided the lighting can be turned OFF in accordance with the applicable provisions in Section 150.0(k)2 while allowing the fan to continue to operate.

C.   Lighting shall have readily accessible wall-mounted controls that allow the lighting to be manually turned ON and OFF.

EXCEPTION to Section 150.0(k)2C: Ceiling fans may provide control of integrated lighting via a remote control.

D.   Lighting controls and equipment shall be installed in accordance with the manufacturer's instructions.

E.   No controls shall bypass a dimmer, occupant sensor or vacancy sensor function where that dimmer or  sensor has been installed to comply with Section 150.0(k).

F.   Lighting controls shall comply with the applicable requirements of Section 110.9.

G.   An Energy Management Control System (EMCS) may be used to comply with control requirements in Section 150.0(k) if at a minimum it provides the functionality of the specified controls in accordance with Section 110.9, meets the installation certificate requirements in Section 130.4 meets the EMCS requirements in Section 130.0(e), and complies with all other applicable requirements in Section 150.0(k)2.

H.   A multiscene programmable controller may be used to comply with dimmer requirements in Section 150.0(k) if at a minimum it provides the functionality of a dimmer in accordance with Section 110.9, and complies with all other applicable requirements in Section 150.0(k)2.

I.    In bathrooms, garages, laundry rooms, and utility rooms, at least one luminaire in each of these spaces shall be controlled by an occupant or vacancy sensor providing automatic-off functionality. If an occupant  sensor is installed, it shall be initially configured to manual-on operation using the manual control required under Section 150.0(k)2C.

J.   Luminaires that are or contain light sources that meet Reference Joint Appendix JA8  requirements for dimming, and that are not controlled by occupancy or vacancy sensors, shall have dimming controls.

EXCEPTION 1 to Section 150.0(k)2J: Luminaires in closets less than 70 square feet.

EXCEPTION 2 to Section 150.0(k)2J: Luminaires in hallways.

K.   Undercabinet lighting shall be controlled separately from ceiling-installed lighting such that one can be turned on without turning on the other.

3.   Residential Outdoor Lighting.

In addition to meeting the requirements of Section 150.0(k)1A, luminaires providing residential outdoor lighting shall meet the following requirements, as applicable:

A.   For single-family residential buildings, outdoor lighting permanently mounted to a residential building, or to other buildings on the same lot, shall meet the requirement in item i and the requirements in either item ii or item iii:

i. Controlled by a manual ON and OFF switch that permits the automatic actions of items ii or iii below; and

ii. Controlled by a photocell and either a motion sensor or an automatic time switch control or

iii. Controlled by an astronomical time clock control.

Controls that override to ON shall not be allowed unless the override automatically returns the automatic control to its normal operation within 6 hours. An energy management control system that provides the specified lighting control functionality and complies with all requirements applicable to the specified controls may be used to meet these requirements.

B.   For low-rise residential buildings with four or more dwelling units, outdoor lighting for private patios, entrances, balconies, porches; and residential parking lots and carports with less than eight vehicles per site shall comply with either:

i. Section 150.0(k)3A; or

ii. The applicable requirements in Sections 110.9, 130.0, 130.2, 130.4, 140.7 and 141.0.

C.   For low-rise residential buildings with four or more dwelling units, any outdoor lighting for residential parking lots or carports with a total of eight or more vehicles per site and any outdoor lighting not regulated by Section 150.0(k)3B or 150.0(k)3D shall comply with the applicable requirements in Sections 110.9, 130.0, 130.2, 130.4, 140.7 and 141.0.

4.   Internally illuminated address signs.

Internally illuminated address signs shall either:

A.   Comply with Section 140.8; or

B.   Consume no more than 5 watts of power.

5.   Residential Garages for Eight or More Vehicles.

Lighting for residential parking garages for eight or more vehicles shall comply with the applicable requirements for nonresidential garages in Sections 110.9, 130.0, 130.1, 130.4, 140.6, and 141.0.

6.   Interior Common Areas of Low-rise Multifamily Residential Buildings.

A.   In a low-rise multifamily residential building where the total interior common area in a single building equals 20 percent or less of the floor area, permanently installed lighting for the interior common areas in that building shall comply with Table 150.0-A and be controlled by an occupant sensor.

B.   In a low-rise multifamily residential building where the total interior common area in a single building equals more than 20 percent of the floor area, permanently installed lighting for the interior common areas in that building shall:

i.    Comply with the applicable requirements in Sections 110.9, 130.0, 130.1, 140.6 and 141.0; and

ii.    Lighting installed in corridors and stairwells shall be controlled by occupant sensors that reduce the lighting power in each space by at least 50 percent. The occupant sensors shall be capable of turning the light fully on and off from all designed paths of ingress and egress.

(l)         Reserved

(m)      Air-Distribution and Ventilation System Ducts, Plenums, and Fans.

1.   CMC Compliance.

A.   All air-distribution system ducts and plenums, including, but not limited to, mechanical closets and air-handler boxes, shall meet the requirements of the CMC Sections 601.0, 602.0, 603.0, 604.0, 605.0 and ANSI/SMACNA-006-2006 HVAC Duct Construction Standards Metal and Flexible 3rd Edition, incorporated herein by reference.

B.   Portions of supply-air and return-air ducts and plenums of a space heating or cooling system shall either be insulated to:

i.    a minimum installed level of R-6.0, or

ii.    a minimum installed level of R-4.2 when the duct system is located entirely in conditioned space as confirmed through field verification and diagnostic testing in accordance with the requirements of Reference Residential Appendix RA3.1.4.3.8.

EXCEPTION 1 to Section 150.0(m)1B: Portions of the duct system located in wall cavities are not required to be insulated if the following conditions are met:

i.   The cavity, duct or plenum is located entirely inside the building’s thermal envelope as confirmed by visual inspection.

ii.  At all locations where portions of non-insulated cavities, ducts, or plenums make a transition into unconditioned space, the transition shall be air-sealed to prevent air infiltration into the cavity and be insulated to a minimum of R-6 as confirmed by visual inspection.

EXCEPTION 2 to Section 150.0(m)1B: Portions of the duct system completely exposed and surrounded by directly conditioned space are not required to be insulated.

C.   Connections of metal ducts and the inner core of flexible ducts shall be mechanically fastened.

D.   Openings shall be sealed with mastic, tape, or other duct-closure system that meets the applicable requirements of UL 181, UL 181A or UL 181B or aerosol sealant that meets the requirements of UL 723. If mastic or tape is used to seal openings greater than 1/4 inch, the combination of mastic and either mesh or tape shall be used.

E.   Building cavities, support platforms for air handlers, and plenums designed or constructed with materials other than sealed sheet metal, duct board or flexible duct shall not be used for conveying conditioned air. Building cavities and support platforms may contain ducts. Ducts installed in cavities and support platforms shall not be compressed to cause reductions in the cross-sectional area of the ducts.

EXCEPTION to Section 150.0(m)1: Ducts and fans integral to a wood heater or fireplace.

2.   Factory-Fabricated Duct Systems.

A.   All factory-fabricated duct systems shall comply with UL 181 for ducts and closure systems, including collars, connections, and splices, and be labeled as complying with UL 181. UL 181 testing may be performed by UL laboratories or a laboratory approved by the Executive Director.

B.   All pressure-sensitive tapes, heat-activated tapes, and mastics used in the manufacture of rigid fiberglass ducts shall comply with UL 181 and UL 181A.

C.   All pressure-sensitive tapes and mastics used with flexible ducts shall comply with UL 181 and UL 181B.

D.   Joints and seams of duct systems and their components shall not be sealed with cloth back rubber adhesive duct tapes unless such tape is used in combination with mastic and drawbands.

3.   Field-Fabricated Duct Systems.

A.   Factory-made rigid fiberglass and flexible ducts for field-fabricated duct systems shall comply with UL 181. All pressure-sensitive tapes, mastics, aerosol sealants, or other closure systems used for installing field-fabricated duct systems shall meet the applicable requirements of UL 181, UL 181A, and UL 181B.

B.   Mastic sealants and mesh.

i.    Sealants shall comply with the applicable requirements of UL 181, UL 181A, and UL 181B, and be nontoxic and water resistant.

ii.    Sealants for interior applications shall be tested in accordance with ASTM C731 and D2202, incorporated herein by reference.

iii.   Sealants for exterior applications shall be tested in accordance with ASTM C731, C732, and D2202, incorporated herein by reference.

iv.   Sealants and meshes shall be rated for exterior use.

C.   Pressure-sensitive tape. Pressure-sensitive tapes shall comply with the applicable requirements of UL 181, UL 181A, and UL 181B.

D.   Joints and seams of duct systems and their components shall not be sealed with cloth back rubber adhesive duct tapes unless such tape is used in combination with mastic and drawbands.

E.   Drawbands used with flexible duct.

i.    Drawbands shall be either stainless-steel worm-drive hose clamps or UV-resistant nylon duct ties.

ii.    Drawbands shall have a minimum tensile strength rating of 150 pounds.

iii.   Drawbands shall be tightened as recommended by the manufacturer with an adjustable tensioning tool.

F.   Aerosol-sealant closures.

i.    Aerosol sealants shall meet the requirements of UL 723 and be applied according to manufacturer specifications.

ii.    Tapes or mastics used in combination with aerosol sealing shall meet the requirements of this section.

4.   Duct Insulation R-value Ratings.

All duct insulation product R-values shall be based on insulation only (excluding air films, vapor retarder, or other duct components) and tested C-values at 75°F mean temperature at the installed thickness, in accordance with ASTM C518 or ASTM C177, incorporated herein by reference, and certified pursuant to Section 110.8.

5.   Duct Insulation Thickness.

The installed thickness of duct insulation used to determine its R-value shall be determined as follows:

A.   For duct board, duct liner, and factory-made rigid ducts not normally subjected to compression, the nominal insulation thickness shall be used.

B.   For duct wrap, installed thickness shall be assumed to be 75 percent (25 percent compression) of nominal thickness.

C.   For factory-made flexible air ducts, the installed thickness shall be determined by dividing the difference between the actual outside diameter and nominal inside diameter by two.

6.   Duct Labeling.

Insulated flexible duct products installed to meet this requirement shall include labels, in maximum intervals of 3 feet, showing the thermal performance R-value for the duct insulation itself (excluding air films, vapor retarder, or other duct components), based on the tests in Section 150.0(m)4 and the installed thickness determined by Section 150.0(m)5C.

7.   Backdraft Dampers.

All fan systems, regardless of volumetric capacity, that exchange air between the building conditioned space and the outside of the building shall be provided with backdraft or automatic dampers to prevent unintended air leakage through the fan system when the fan system is not operating.

8.   Gravity Ventilation Dampers.

All gravity ventilating systems that serve conditioned space shall be provided with either automatic or readily accessible, manually operated dampers in all openings to the outside except combustion inlet and outlet air openings and elevator shaft vents.

9.   Protection of Insulation.

Insulation shall be protected from damage, including that due to sunlight, moisture, equipment maintenance, and wind but not limited to the following: Insulation exposed to weather shall be suitable for outdoor service (e.g., protected by aluminum, sheet metal, painted canvas, or plastic cover). Cellular foam insulation shall be protected as above or painted with a coating that is water retardant and provides shielding from solar radiation that can cause degradation of the material.

10.  Porous Inner Core Flex Duct.

Flexible ducts having porous inner cores shall have a non-porous layer or air barrier between the inner core and the outer vapor barrier.

11.  Duct System Sealing and Leakage Testing.

When space conditioning systems utilize forced air duct systems to supply conditioned air to an occupiable space, the ducts shall be sealed, as confirmed through field verification and diagnostic testing, in accordance with all applicable procedures specified in Reference Residential Appendix RA3.1, and the leakage compliance criteria specified in Reference Residential Appendix TABLE RA3.1-2, and conforming to one of the following Subsections A, B, or C as applicable:

A.   For single family dwellings and townhouses with the air-handling unit installed and the ducts connected directly to the air handler, the total leakage of the duct system shall not exceed 5 percent of the nominal system air handler airflow as determined utilizing the procedures in Reference Residential Appendix Section RA3.1.4.3.1.

B.   For single family dwellings and townhouses at the rough-in stage of construction prior to installation of the dwelling's interior finishing:

i.    Air-handling unit installed.

If the air-handling unit is installed and the ducts are connected directly to the air handler, the total leakage of the duct system shall not exceed 5 percent of the nominal system air handler airflow as determined utilizing the procedures in Reference Residential Appendix Sections RA3.1.4.3.2, RA3.1.4.3.2.1 and RA3.1.4.3.3.

ii.   Air-handling unit not yet installed.

If the air-handling unit is not yet installed, the total leakage of the duct system shall not exceed 4 percent of the nominal system air handler airflow as determined utilizing the procedures in Reference Residential Appendix Sections RA3.1.4.3.2, RA3.1.4.3.2.2 and RA3.1.4.3.3.

C.   For multifamily dwellings with the air-handling unit installed and the ducts connected directly to the air handler, regardless of duct system location:

i.    The total leakage of the duct system shall not exceed 12 percent of the nominal system air handler airflow as determined utilizing the procedures in Reference Residential Appendix Section RA3.1.4.3.1; or

ii.    The duct system leakage to outside shall not exceed 6 percent of the nominal system air handler airflow as determined utilizing the procedures in Reference Residential Appendix Section RA3.1.4.3.4.

12.  Air Filtration.

A.   System types specified in subsections i, ii, and iii shall be provided with air filters in accordance with Sections 150.0(m)12B, 150.0(m)12C, and 150.0(m)12D. System types specified in subsection i shall also comply with Section 150.0(m)12E.

i.    Mechanical space conditioning systems that supply air to an occupiable space through ductwork exceeding 10 ft (3 m) in length.

ii.    Mechanical supply-only ventilation systems that provide outside air to an occupiable space.

iii.   The supply side of mechanical balanced ventilation systems, including heat recovery ventilation systems, and energy recovery ventilation systems that provide outside air to an occupiable space.

EXCEPTION 1 to Section 150.0(m)12A: Evaporative coolers are exempt from the air filtration requirements in Section 150.0(m)12.

B.   System Design and Installation.

i. The system shall be designed to ensure that all recirculated air and all outdoor air supplied to the occupiable space is filtered before passing through any system’s thermal conditioning components.

EXCEPTION 1 to Section 150.0(m)12Bi: For heat recovery ventilators and energy recovery ventilators the location of the filters required by Section 150.0(m)12 may be downstream of a system thermal conditioning component, provided the system is equipped with ancillary filtration upstream of the system’s thermal conditioning component.

ii. All systems shall be designed to accommodate the clean-filter pressure drop imposed by the system air filter(s). The design airflow rate, and maximum allowable clean-filter pressure drop at the design airflow rate applicable to each air filter shall be determined and reported on labels according to subsection iv below.

Systems specified in Section 150.0(m)12Ai shall be equipped with air filters that meet either subsection a or b below.

a. Nominal two-inch minimum depth filter(s) shall be sized by the system designer, or

b. Nominal one-inch minimum depth filter(s) shall be allowed if the filter(s) are sized according to Equation 150.0-A, based on a maximum face velocity of 150 ft per minute, and according to the maximum allowable clean-filter pressure drop specified in Section 150.0(m)12Dii.

Equation 150.0-A

A_face = Q_filter / V_face

where

A_face = air filter face area, the product of air filter nominal length x nominal width, ft²

Q_filter = design airflow rate for the air filter, ft³/min

V_face = air filter face velocity ≤ 150, ft/min

iii.      All system air filters shall be located and installed in such a manner as to be accessible for regular service by the system owner.

iv.      All system air filter installation locations shall be labeled to disclose the applicable design airflow rate and the maximum allowable clean-filter pressure drop. The labels shall be permanently affixed to the air filter installation location, readily legible, and visible to a person replacing the air filter

C.   Air Filter Efficiency.

The system shall be provided with air filters having a designated efficiency equal to or greater than MERV 13 when tested in accordance with ASHRAE Standard 52.2, or a particle size efficiency rating equal to or greater than 50 percent in the 0.30-1.0 μm range and equal to or greater than 85 percent in the 1.0-3.0 μm range when tested in accordance with AHRI Standard 680.

D.   Air Filter Pressure Drop.

All systems shall be provided with air filters that conform to the applicable maximum allowable clean-filter pressure drop specified in subsections i, ii, iii, or iv below, when tested using ASHRAE Standard 52.2, or as rated using AHRI Standard 680, for the applicable design airflow rates for the system air filters.

i.    The maximum allowable clean-filter pressure drop determined by the system design for the nominal two-inch minimum depth air filter required by Section 150.0(m)12Biia, or

ii.    A maximum of 25 PA (0.1 inches water) clean-filter pressure drop shall be allowed for a nominal one-inch depth air filter sized according to Section 150.0(m)12Biib, or

iii.   For systems specified in 150.0(m)12Aii, and 150.0(m)12Aiii, the maximum allowable clean filter pressure drop determined by the system design.

iv.   If EXCEPTION 1 to Section 150.0(m)13B or D is utilized for compliance with cooling system airflow rate and fan efficacy requirements, the clean-filter pressure drop for the system air filter shall conform to the requirements given in TABLE 150.0-B or 150.0-C.

E.      Air Filter Product Labeling.

Systems described in 150.0(m)12)Ai shall be equipped with air filters that have been labeled by the manufacturer to disclose the efficiency and pressure drop ratings that demonstrate conformance with Sections 150.0(m)12C and 150.0(m)12D.

13.  Space Conditioning System Airflow Rate and Fan Efficacy.

Space conditioning systems that utilize forced air ducts to supply cooling to an occupiable space shall:

A.   Static Pressure Probe. Have a hole for the placement of a static pressure probe (HSPP), or a permanently installed static pressure probe (PSPP) in the supply plenum downstream of the air conditioning evaporator coil. The size, location, and labeling of the HSPP or PSPP shall conform to the requirements specified in Reference Residential Appendix RA3.3.1.1 as confirmed by field verification and diagnostic testing; and

EXCEPTION to 150.0(m)13A: Systems that cannot conform to the specifications for hole location in Reference Residential Appendix Figure RA3.3-1 shall not be required to provide holes as described in Figure RA3.3-1.

B.   Single Zone Central Forced Air Systems.

Demonstrate, in every control mode, airflow greater than or equal to 350 CFM per ton of nominal cooling capacity through the return grilles, and an air-handling unit fan efficacy less than or equal to the maximum W/CFM specified in subsections i or ii below. The airflow rate and fan efficacy requirements in this section shall be confirmed by field verification and diagnostic testing in accordance with the procedures given in Reference Residential Appendix RA3.3

i.    0.45 W/CFM for gas furnace air-handling units.

ii.    0.58 W/CFM for air-handling units that are not gas furnaces.

C.   Zonally Controlled Central Forced Air Systems.

Zonally controlled central forced air cooling systems shall be capable of simultaneously delivering, in every zonal control mode, an airflow from the dwelling, through the air handler fan and delivered to the dwelling, of greater than or equal to 350 CFM per ton of nominal cooling capacity, and operating at an air-handling unit fan efficacy of less than or equal to the maximum W/CFM specified in subsections i or ii below. The airflow rate and fan efficacy requirements in this section shall be confirmed by field verification and diagnostic testing in accordance with the applicable procedures specified in Reference Residential Appendix RA3.3.

i.    0.45 W/CFM for gas furnace air-handling units.

ii.    0.58 W/CFM for air-handling units that are not gas furnaces.

D.   Small Duct High Velocity Forced Air Systems. Demonstrate, in every control mode, airflow greater than or equal to 250 CFM per ton of nominal cooling capacity through the return grilles, and an air-handling unit fan efficacy less than or equal to 0.62 W/CFM as confirmed by field verification and diagnostic testing in accordance with the procedures given in Reference Residential Appendix RA3.3

EXCEPTION 1 to Section 150.0(m)13B and D: Standard ducted systems without zoning dampers may comply by meeting the applicable requirements in  TABLE 150.0-B or 150.0-C as confirmed by field verification and diagnostic testing in accordance with the procedures in Reference Residential Appendix Section RA3.1.4.4 and RA3.1.4.5. The design clean-filter pressure drop requirements specified by Section 150.0(m)12Div for the system air filter(s) shall conform to the requirements given in TABLES 150.0-B and 150.0-C.

EXCEPTION 2 to Section 150.0(m)13B and D: Multispeed compressor systems or variable speed compressor systems shall verify airflow (cfm/ton) and fan efficacy (Watt/cfm) for system operation at the maximum compressor speed and the maximum air handler fan speed.

EXCEPTION 3 to Section 150.0(m)13B: Gas furnace air-handling units manufactured prior to July 3, 2019 shall comply with a fan efficacy value less than or equal to 0.58 w/cfm as confirmed by field verification and diagnostic testing in accordance with the procedures given in Reference Residential Appendix RA3.3.

EXCEPTION 1 to Section 150.0(m)13C: Multispeed or variable speed compressor systems, or single speed compressor systems that utilize the performance compliance approach, shall demonstrate compliance with the airflow (cfm/ton) and fan efficacy (Watt/cfm) requirements of Section 150.0(m)13C by operating the system at maximum compressor capacity and system fan speed with all zones calling for conditioning, rather than in every zonal control mode.

EXCEPTION 2 to Section 150.0(m)13C: Gas furnace air-handling units manufactured prior to July 3, 2019 shall comply with a fan efficacy value less than or equal to 0.58 w/cfm as confirmed by field verification and diagnostic testing in accordance with the procedures given in Reference Residential Appendix RA3.3.

(n)       Water Heating System.

1.   Systems using gas or propane water heaters to serve individual dwelling units shall include the following components:

A.   A dedicated 125 volt, 20 amp electrical receptacle that is connected to the electric panel with a 120/240 volt 3 conductor, 10 AWG copper branch circuit, within 3 feet from the water heater and accessible to the water heater with no obstructions.  In addition, all of the following:

i. Both ends of the unused conductor shall be labeled with the word “spare” and be electrically isolated; and

ii.  A reserved single pole circuit breaker space in the electrical panel adjacent to the circuit breaker for the branch circuit in A above and labeled with the words “Future 240V Use”; and

B.   A Category III or IV vent, or a Type B vent with straight pipe between the outside termination and the space where the water heater is installed; and

C.   A condensate drain that is no more than 2 inches higher than the base of the installed water heater, and allows natural draining without pump assistance, and

D.   A gas supply line with a capacity of at least 200,000 Btu/hr.

2.   Water heating recirculation loops serving multiple dwelling units shall meet the requirements of Section 110.3(c)5.

3.   Solar water-heating systems and collectors shall be certified and rated by the Solar Rating and Certification Corporation (SRCC), the International Association of Plumbing and Mechanical Officials, Research and Testing (IAPMO R&T), or by a listing agency that is approved by the Executive Director.

4.   Instantaneous water heaters with an input rating greater than 6.8 kBTU/hr (2kW) shall meet the requirements of Section 110.3(c)7.

(o)       Requirements for Ventilation and Indoor Air Quality.

All dwelling units shall meet the requirements of ASHRAE Standard 62.2, Ventilation and Acceptable Indoor Air Quality in Residential Buildings subject to the amendments specified in Section 150.0(o)1 below. All dwelling units shall comply with Section 150.0(o)2 below.

1.   Amendments to ASHRAE 62.2 requirements.

A    Window operation is not a permissible method of providing the dwelling unit ventilation airflow specified in subsections C, E, or F below.

B.   Continuous operation of central forced air system air handlers used in central fan integrated ventilation systems is not a permissible method of providing the dwelling unit ventilation airflow required in Section 4 of ASHRAE Standard 62.2.

C    Single family detached dwelling units, and attached dwelling units not sharing ceilings or floors with other dwelling units, occupiable spaces, public garages, or commercial spaces shall have mechanical ventilation airflow provided at rates determined in accordance with ASHRAE 62.2 Sections 4.1.1 and 4.1.2 as specified in subsections i, ii, and iii below.

i.    Total Required Ventilation Rate [ASHRAE 62.2:4.1.1].

The total required ventilation rate shall be calculated using Equation 150.0-B

Equation 150.0-B

Qtot = 0.03Afloor + 7.5(Nbr + 1)

where

Qtot = total required ventilation rate, cfm

Afloor = dwelling-unit floor area, ft2

Nbr = number of bedrooms (not to be less than 1)

ii.    Effective Annual Average Infiltration Rate. The effective annual average infiltration rate shall be determined in accordance with subsections a and b:

a.   An enclosure leakage rate in cubic feet per minute at 50 Pa (0.2 inch water) (Q₅₀) shall be determined by either subsection 1, or subsection 2 below.

1.   Q₅₀ shall be calculated based on the conditioned volume of the dwelling unit and a default value for dwelling unit envelope leakage of 2 air changes per hour at 50 PA (0.2 inch water) (2 ACH₅₀) as specified by equation 150.0-C below.

Equation 150.0-C

Q₅₀ = V_du x 2 ACH₅₀ / 60 min

where

Q₅₀ = leakage rate at 50 Pa

V_du = dwelling unit conditioned volume, ft³

ACH₅₀ = air changes per hour at 50 Pa (0.2 inch water)

2.   If dwelling unit envelope leakage less than 2 ACH₅₀ is confirmed by field verification and diagnostic testing, Q₅₀ shall be calculated according to Equation 150.0-D below, using the value for dwelling unit envelope leakage less than 2 ACH₅₀ verified by the procedures specified in Reference Residential Appendix RA3.8.

Equation 150.0-D

Q₅₀ = V_du x Verified ACH₅₀ / 60 min

where

Q₅₀ = leakage rate at 50 Pa

V_du = dwelling unit conditioned volume, ft³

ACH₅₀ = air changes per hour at 50 Pa (0.2 inch water)

b.   The Effective Annual Average Infiltration Rate (Q_inf) shall be calculated using Equation 150.0-E [ASHRAE 62.2:4.1.2.1].

Equation 150.0-E

Q_inf = 0.052 × Q₅₀ × wsf × [H/H_r]^z

where

Q_inf = effective annual infiltration rate, cfm (L/s)

Q₅₀ = leakage rate at 50 Pa from equation 150.0-C, or equation 150.0-D

wsf = weather and shielding factor from Table 150.0-D

H = vertical distance between the lowest and highest above-grade points within the pressure boundary, ft (m)

H_r = reference height, 8.2 ft (2.5 m)

z = 0.4 for the purpose of calculating the Effective Annual Average Infiltration Rate

iii.         Required Mechanical Ventilation Rate [ASHRAE 62.2:4.1.2]

The Required Mechanical Ventilation Rate (Q_fan) shall be calculated using Equation 150.0-F

Equation 150.0-F

Q_fan = Q_tot – Φ (Q_inf  × A_ext)

where

Q_fan = required mechanical ventilation rate, cfm (L/s)

Q_tot = total required ventilation rate, cfm (L/s) from Equation 150.0-B.

Q_inf = effective annual average infiltration rate, cfm (L/s) from Equation 150.0-E

A_ext = 1 for single-family detached homes, or the ratio of exterior envelope surface area that is not attached to garages or other dwelling units to total envelope surface area for attached dwelling units not sharing ceilings or floors with other dwelling units, occupiable spaces, public garages, or commercial spaces.

Φ=1 for balanced ventilation systems and Q_inf/Q_tot otherwise

D.   Air filtration shall conform to the specifications in Section 150.0(m)12. Compliance with ASHRAE 62.2 Sections 6.7 (Minimum Filtration) and 6.7.1 (Filter Pressure Drop) shall not be required.

E.   Multifamily attached dwelling units shall have mechanical ventilation airflow provided at rates in accordance with Equation 150.0-B [ASHRAE 62.2:4.1.1], and comply with one of the following subsections i or ii below. When subsection ii below is utilized for compliance, all dwelling units in the multifamily building shall use the same ventilation system type.

i.    A balanced ventilation system shall provide the required dwelling-unit ventilation airflow, or

ii.    Continuously operating supply ventilation systems, or continuously operating exhaust ventilation systems shall be allowed to be used to provide the required dwelling unit ventilation airflow if the dwelling-unit envelope leakage is less than or equal to 0.3 cubic feet per minute at 50 Pa (0.2 inch water) per ft² of dwelling unit envelope surface area as confirmed by field verification and diagnostic testing in accordance with the procedures specified in Reference Residential Appendix RA3.8.

F.   Multifamily building central ventilation systems that serve multiple dwelling units shall be balanced to provide ventilation airflow for each dwelling unit served at a rate equal to or greater than the rate specified by Equation 150.0-B [ASHRAE 62.2:4.1.1], but no more than twenty percent greater than the specified rate. These systems shall utilize balancing means to ensure the dwelling-unit airflows can be adjusted to meet this balancing requirement. These system balancing means may include but not be limited to constant air regulation devices, orifice plates, and variable speed central fans.

G.   Kitchen range hoods shall be rated for sound in accordance with Section 7.2 of ASHRAE 62.2.

      EXCEPTION to Section 150.0(o)1G: Kitchen range hoods may be rated for sound at a static pressure determined at working speed as specified in HVI 916 section 7.2.

H.   Compliance with ASHRAE 62.2 Section 6.5.2 (Space Conditioning System Ducts) shall not be required.

I.    Compliance with ASHRAE 62.2 Section 4.4 (Control and Operation) shall require manual switches associated with dwelling unit ventilation systems to have a label clearly displaying the following text, or equivalent text: "This switch controls the indoor air quality ventilation for the home. Leave it on unless the outdoor air quality is very poor."

2.   Field Verification and Diagnostic Testing.

A.   Airflow Performance.

The dwelling unit ventilation airflow required by Sections 150.0(o)1C, 150.0(o)1E, and 150.0(o)1F shall be confirmed through field verification and diagnostic testing in accordance with the applicable procedures specified in Reference Residential Appendix RA3.7.

B    Kitchen Range Hoods. The installed kitchen range hood shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.7.4.3 to confirm the model is rated by HVI to comply with the following requirements:

i.    The minimum ventilation airflow rate as specified in Section 5 of ASHRAE 62.2.

ii     The maximum sound rating as specified in Section 150.0(o)1G.

(p)       Pool Systems and Equipment Installation.

Any residential pool system or equipment installed shall comply with the applicable requirements of Section 110.4, as well as the requirements 'listed’ in this section.

1.   Pump sizing and flow rate.

A.   All pumps and pump motors installed shall be 'listed in the Commission’s directory of certified equipment and shall comply with the Appliance Efficiency Regulations.

B.   All pump flow rates shall be calculated using the following system equation:

WHERE:

H is the total system head in feet of water.

F is the flow rate in gallons per minute (gpm).

C is a coefficient based on the volume of the pool:

0.0167 for pools less than or equal to 17,000 gallons.

0.0082 for pools greater than 17,000 gallons.

C.   Filtration pumps shall be sized, or if programmable, shall be programmed, so that the filtration flow rate is not greater than the rate needed to turn over the pool water volume in 6 hours or 36 gpm, whichever is greater; and

D.   Pump motors used for filtration with a capacity of 1 hp or more shall be multispeed; and

E.   Each auxiliary pool load shall be served by either separate pumps or the system shall be served by a multispeed pump; and

EXCEPTION to Section 150.0(p)1E: Pumps less than 1 hp may be single speed.

F.   Multispeed pumps shall have controls which default to the filtration flow rate when no auxiliary pool loads are operating; and

G.   For multispeed pumps, the controls shall default to the filtration flow rate setting within 24 hours and shall have an override capability for servicing.

2.   System piping.

A.   A length of straight pipe that is greater than or equal to at least 4 pipe diameters shall be installed before the pump; and

B.   Pool piping shall be sized so that the velocity of the water at maximum flow for auxiliary pool loads does not exceed 8 feet per second in the return line and 6 feet per second in the suction line; and

C.   All elbows shall be sweep elbows or of an elbow-type that has a pressure drop of less than the pressure drop of straight pipe with a length of 30 pipe diameters.

3.   Filters. Filters shall be at least the size specified in NSF/ANSI 50 for public pool intended applications.

4.   Valves. Minimum diameter of backwash valves shall be 2 inches or the diameter of the return pipe, whichever is greater.

(q)       Fenestration Products.

Fenestration separating conditioned space from unconditioned space or outdoors shall meet the requirements of either Item 1 or 2 below:

1.   Fenestration, including skylight products, must have a maximum U-factor of 0.58.

EXCEPTION 1 to Section 150.0(q)1: Up to 10 square feet of fenestration area or 0.5 percent of the Conditioned Floor Area, whichever is greater, is exempt from the maximum U-factor requirement.

EXCEPTION 2 to Section 150.0(q)1: For dual-glazed greenhouse or garden windows, up to 30 square feet of fenestration area is exempt from the maximum U-factor requirement.

2.   The weighted average U-factor of all fenestration, including skylight products, shall not exceed 0.58.

(r)        Solar Ready Buildings.

Shall meet the requirements of Section 110.10 applicable to the building project.

TABLE 150.0-A CLASSIFICATION OF HIGH EFFICACY LIGHT SOURCES

TABLE 150.0-B: Return Duct Sizing for Single Return Duct Systems

TABLE 150.0-C:  Return Duct Sizing for Multiple Return Duct Systems

TABLE 150.0-D: Infiltration Effectiveness Weather and Shielding Factors [ASHRAE 62.2:Table B1]

TABLE 150.0-D: Infiltration Effectiveness Weather and Shielding Factors [ASHRAE 62.2:Table B1] (continued)

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.