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Quarterly News for California Building Departments

Issue #56, Oct - Dec 2017

Residential Multiwire Branch Circuits

Avoid Danger of Electrocution

By Dan Chudy, Ph.D., CBO, LEED AP, CASp
Principal Project Manager – Willdan Engineering

One of the most common corrections that I write on residential electrical service panel wiring has to do with incorrectly wired multiwire branch circuits.  A multiwire branch circuit is defined in the National Electrical Code (see Article 100 – Branch Circuit, Multiwire) as basically two or more circuits that have a voltage between them and that share a common neutral.   Having a voltage between them is another way of saying that the two circuits are supplied by different buses (poles) in the panel.  A multiwire branch circuit in residential installations is typically observed when a 3-wire plus a ground Romex cable (NMC) is used. The quickest and easiest way to determine if a multiwire branch circuit has been used in a typical residential electrical panel is to look for a red wire originating from a Romex cable. 

The National Electrical Code requires that a few very important things are accomplished when multiwire branch circuits are used:

  1. Handle ties are required on multiwire branch circuit breakers and when 2 or more circuits share the same yolk (i.e. when a garbage disposal and a dish washer share the same outlet and are served by different circuits.  See NEC 210.4(B), 210.7, and 230.71(B).

Single and double pole breakers used on multiwire branch circuits must be connected with handle ties. Handle ties are for the safety of those working on the electrical system.  One possible safety scenario, if the multiwire branch circuit did NOT have the handle tie to lock both circuits together is as follows: One of the two circuits is shut OFF at the panel (the other is left ON) and the electrician or home owner goes to work on a receptacle on the OFF circuit.  The neutral wire (which serves both circuits) is still carrying current from the circuit which is still ON and thus a shock condition is possible even though the circuit is OFF.

A second potential safety scenario would occur if only one of the two circuits within the outlet box were turned off and the unknowing home owner or electrician assumed that all current carrying conductors in that box were OFF.  Consider the previously mentioned dish washer/garbage disposal outlets under the kitchen sink.  The unknowing individual wants to do some work on the garbage disposal circuit so he/she turns off the breaker in the main panel and then goes to work, not knowing that there are other live wires inside that outlet box (that is, not knowing until the live wire touches a finger).

  1. Single pole breakers may be used on multiwire branch circuits if they are connected by a handle tie.  See NEC 240.15(B)(1).

The biggest potential problem with allowing single pole breakers is that they could be connected to the same hot bus (same pole) and thus result in an unsafe overload condition on the common neutral wire.  In a typical residential electrical system, two electrical currents on opposing electrical phases (aka: different hot buses or poles) when applied to the same conductor are self-canceling, thus the common neutral is capable of handling the electrical load of two circuits.  However, if those same two electrical currents are from the same electrical phase (i.e. pole), the electrical currents on the neutral conductor will ADD instead of cancelling each other out.  This will overload the common neutral conductor.

Single pole circuit breakers need to be on different hot buses (different poles) in the electrical panel or an overload condition will occur on the neutral wire.  Even when the single pole breakers are installed correctly on different poles, they could potentially be relocated at a future time by an unknowing home owner (or unknowledgeable contractor) creating an overloaded neutral.  This is why the handle tie is so critical.  It serves two functions: First, it alerts the home owner and future contractor that the two circuits need to be tied together; and Secondly, the handle tie assures that each circuit breaker is on a different hot bus (i.e. different pole).  Unfortunately, two single pole breakers that are connected by a handle tie can be easily separated by removal of the handle tie device, and subsequently relocated to other locations within the panel.

Double pole or two pole circuit breakers are recommended to be used on multiwire branch circuits (but not required by code) because they are designed to connect to different poles and they can’t be inadvertently separated and relocated to the same bus by an unknowing person at a later date.  

Be aware that many of the “tandem” thin breakers contain two circuit breakers that are supplied from a single pole.  These are the skinny side-by-side breakers that are sometimes used to save space in the panel in order to add more breakers.  Essentially, you can fit two breakers where one typically fits.  These types of doubled-up single pole breakers are not appropriate to use on multiwire branch circuits because both circuits are served from the same pole (bus) and an overload of the neutral will occur as discussed above.

Typical residential 3-wire plus ground Romex (NMC) entering a service panel:

3-wire entering service panel

Typical residential 3-wire plus ground Romex (NMC) within a service panel:

3-wire within panel

Incorrectly installed multiwire branch circuit, no handle tie provided:


Correctly installed multiwire branch circuit with handle tie provided:

  1. The code also requires that the neutral wire (of a multiwire branch circuit) maintain its continuity when a device (i.e. receptacle outlet) is removed.  This means that you need to pigtail the neutral wire connections in the outlet boxes.  See NEC 300.13(B).
  2. Because it can be very difficult to distinguish which wires are part of a multiwire branch circuit in a panel that is full of many conductors, the code requires that the ungrounded and grounded circuit conductors of each multiwire branch circuit be grouped by cable ties or similar means in at least one location within the panel.  See NEC 210.4(D).  There are exceptions if the wires which make up the multiwire circuits are obvious when they enter the panel or if the multiwire circuits are identified at their terminations in the panel with appropriate circuit numbering wire tags.

This code requirement becomes critically important in those electrical panels where there are so many incoming wires that it is nearly impossible to distinguish which black and red wire (which constitute a specific multiwire branch circuit) go together.  I’ve seen some panel upgrades where the wires are so jumbled that it looks like a bowl of spaghetti, and with the power already energized, it becomes dangerous trying to separate the wires to see which two are required to be on adjacent breakers with a common handle tie.

First Christian Church roof repair
CSU San Jose Library

Pictured: A few buildings plan-checked or inspected by Willdan

Focus on the 2016 Codes

2016 California Codes Digest for Dwelling Inspections or Plan Review (Part 3 of a 4-part Series)

code books

Photo: special to Willdan

By Dan Chudy, Ph.D., CBO, LEED AP, CASp
Principal Project Manager – Willdan Engineering

architectural house drawing

A more logical way (at least for me) to organize and consolidate the most common residential code requirements is by segregating them according to the room in the house to which they apply.   With that in mind, I have compiled such a list in alphabetical order by room, and in 2016, the Willdan Letter published the list based on the 2013 California Codes (compiled here).

This year we are updating the list to correlate with the new 2016 California Codes (Running compilation here).

NOTE: Although many of thecode citations herein are carry-overs from the 2013 California Codes, some are new or substantially revised. Those code citations which are either new or substantially revised are highlighted in GREEN. Those code citations that were in the 2013 California Codes, but are not found in the 2016 California codes are highlighted in BLUE. Key words are highlighted in YELLOW in order to assist the user in quickly finding particular items of interest.

Please understand that this effort is a work in progress and I make no claim that the list is all inclusive nor that it is without error. If any errors or omissions are found, please email me at so that the list can be improved.

CODE PROVISIONS SEGREGATED ALPHABETICALLY BY SPECIFIC ROOMS IN DWELLINGS, (based on the 2016 California Codes)
PART 3: H’ (Habitable Space) thru ‘P’ (Patio) in this Willdan Letter edition

Click the + next to each title to view its description, or click the "Show All" button.

HABITABLE SPACE

CRC R202 – Bathrooms, toilet rooms, closets, halls, storage, utility spaces NOT considered habitable space.

CRC R303.1 - All habitable rooms shall have an aggregate glazed area of not less than 8 percent of the floor area, and an openable window area to the outdoors of at least 4 percent for ventilation.

CRC R303.9 – Heat required to minimum 68 degrees F, and measured 3’ above floor and 2‘ from exterior walls.

CRC R304.1 – Habitable rooms shall have a floor area of at least 70 square feet.

CRC R305.1 – Minimum ceiling height 7’-0”.

CRC R308.4.3 – Window glass with bottom edge less than 18” above floor, AND top edge of glass more than 36” above floor, AND exposed area of an individual pane is larger than 9 square feet is required to be safety glass.

CRC R312.2.1 – When fall from window would be more that 72” to surface below, window sill to be 24” min. above floor OR, if less than 24” above floor, window opening shall not allow the passage of a 4” diameter sphere or other device to other approved opening control device.

CEC 210.12(A)Arc-fault circuit interrupter required for outlets in most rooms of house (except: bathrooms, garages, non-habitable attics, unfinished basements, and exterior outlets).

CEC 210.12(B)AFCI circuits wire length limited from AFCI breaker to first receptacle outlet or AFCI receptacle to next receptacle outlet is 50’ maximum for #14 wire and 70’ for #12 wire.  The first AFCI outlet to be marked as such (i.e. “First AFCI Outlet”).

CEC 210.70 (A)(1) – At least (1) wall switched light outlet required in every habitable room and bathroom and hallway, stairway, garage, exterior side of outdoor grade level entrances (garage vehicle doors are exempt).

CEC 406.12 – Tamper resistant receptacle outlets for all non-locking 120V/15 and 20 amp outlets unless for luminaries or over 5.5’ above floor or a single outlet for a single dedicated appliance which is not easily moved or a duplex outlet for (2) dedicated appliances.

150.0(k) – All lighting to be high-efficacy.

HALLWAY

CRC R305.1 – Minimum ceiling height 7’-0”.

CRC R311.6 – Minimum width 36”.

CRC R308.4.3 – Window glass with bottom edge less than 18” above floor, AND top edge of glass more than 36” above floor, AND exposed area of an individual pane is larger than 9 square feet is required to be safety glass.

CRC R312.2.1 – When fall from window would be more that 72” to surface below, window sill to be 24” min. above floor OR, if less than 24” above floor, window opening shall not allow the passage of a 4” diameter sphere or other device to other approved opening control device.

CRC R314.3 – Smoke alarms required in sleeping rooms (aka: bedrooms), outside sleeping room areas in the immediate area of the bedrooms (aka: hallways, etc.), on each story (including basements and habitable attics).  (See also H & S Code 13113.7)

CRC R314.3.3 (excerpt from NFPA 72 Section 29.8.3.4) – Smoke detectors shall not be located in the following areas:

  1. In unfinished attics or garages where the temperature can fall below 40 degrees or above 100 degrees;
  2. Within 20 feet of permanent cooking appliances (Ionization type can be within 10’ and photoelectric type can be within 6’);
  3. Within 3 feet of a bathroom door (with tub or shower) unless there is no other option for placement;
  4. Within 3 feet of an HVAC air supply register;
  5. Within 3 feet of the tips of the blades of a ceiling fan;
  6. In basements stairways the smoke alarm shall be at the bottom of the stairs;
  7. In coffered ceilings the smoke alarm shall be located at the highest portion of the ceiling.

CRC R314.3.3 Removed from 2016 CRC10 year battery only required on smoke alarms if they are the battery only type (not hard wired).  NOTE: THIS REQUIREMENT HAS BEEN REMOVED FROM THE 2016 CRC

CRC R314.4 – Smoke alarms to be interconnected (exceptions for some alterations and repairs).

CRC R315.2.1 – CO alarms NOT required if no fuel-burning appliance and no attached garage.

CRC R315.3 – CO alarms required to be at outside each sleeping area in the immediate vicinity of the bedrooms (aka: hallways, etc.) and on every level (including basement) of the dwelling. (See also H & S Code 17926)

CRC R315.5 – CO alarms to be hard wired with battery backup in new construction and some remodels.

CRC R315.5 Exception 4 – In existing dwellings where alteration do not result in the removal of wall or ceiling finishes a battery only or plug-in CO alarm may be used.

CRC R315.7 – CO alarms to be interconnected when more than 1 unit installed.

CEC 210.12(A)Arc-fault circuit interrupter required for outlets in most rooms of house (except: bathrooms, garages, non-habitable attics, unfinished basements, and exterior outlets).

CEC 210.12(B)AFCI circuits wire length limited from AFCI breaker to first receptacle outlet or AFCI. receptacle to next receptacle outlet is 50’ maximum for #14 wire and 70’ for #12 wire.  The first AFCI outlet to be marked as such (i.e. “First AFCI Outlet”).

CEC 210.52 (H) – Hallways more than 10’ long require at least (1) receptacle outlet (the general rule of 12’ spacing is not applicable to hallways).

CEC 210.70 (A)(1) – At least (1) wall switched light outlet required in every habitable room and bathroom and hallway, stairway, garage, exterior side of outdoor grade level entrances (garage vehicle doors are exempt).

CEC 406.12 – Tamper resistant receptacle outlets for all non-locking 120V/15 and 20 amp outlets unless for luminaries or over 5.5’ above floor or a single outlet for a single dedicated appliance which is not easily moved or a duplex outlet for (2) dedicated appliances.

150.0(k) – All lighting to be high-efficacy.

150.0(k)2(K) Exception – Light dimmers are not required for hallway lights.

150.0(i) – Setback thermostat required unless an Energy Management Control System (ECMS) is installed.

KITCHEN

CRC R303.1 - All habitable rooms shall have an aggregate glazed area of not less than 8 percent of the floor area, and an openable window area to the outdoors of at least 4 percent for ventilation.

CRC R304.2 – Kitchens are exempt from minimum floor area and minimum dimension requirements.

CRC R306.4 – Hot and cold water required to kitchen sink.

CRC R312.2.1 – When fall from window would be more that 72” to surface below, window sill to be 24” min. above floor OR, if less than 24” above floor, window opening shall not allow the passage of a 4” diameter sphere or other device to other approved opening control device.

CRC R314.3.3 – Smoke alarms required to be minimum 20’ from permanent cooking equipment (10’ if ionization type alarm equipped with silencing switch or photoelectric type alarm).

CPC 807.3 – Dishwasher air gap to be installed with the flood-level marking (FL) at or above the flood level of the sink or drain board, whichever is higher.

CMC 311.3(5) – Return air shall not be taken from bathrooms, toilet rooms, kitchens, closet0s.

CMC T403.7 – Kitchen exhaust fan required: 100 cfm if intermittent or 50 cfm if continuous and 3 sone max sound level per T-24 150.0(a) & 150.2(a).

CMC 504.2 Exception - Domestic kitchen downdraft grill-range ventilation installed under a concrete slab floor may be of approved Schedule 40 PVC.

CEC 210.12(A)Arc-fault circuit interrupter required for outlets in most rooms of house (except: bathrooms, garages, non-habitable attics, unfinished basements, and exterior outlets).

CEC 210.12(B)AFCI circuits wire length limited from AFCI breaker to first receptacle outlet or AFCI receptacle to next receptacle outlet is 50’ maximum for #14 wire and 70’ for #12 wire.  The first AFCI outlet to be marked as such (i.e. “First AFCI Outlet”).

CEC 210.8(A)(6) – GFCI outlets required for all counter top outlets and within 6’ of sinks.

CEC 210.8(D)Dishwasher circuits require GFCI protection.

CEC 210.11 (C)(1) and 210.52(B)(1) – Two 20 amp small appliance branch circuits required for kitchen and dining room (including refrigerator outlet) (or refrigerator can be on a dedicated 15 amp or more circuit).

CEC 210.12(A) – AFCI protected outlets required on all 120 volt, 15 and 20 amp kitchen outlets.

CEC 210.52 – Maximum height of required convenience outlets is 5-1/2 feet above the floor.  No minimum height identified (unless for disabled access CBC 1136A.1 - 48” max to top of box and 15” minimum to the bottom of the box).

CEC 210.52(A)1 – Spacing of electrical outlets to be such that no point along the wall line  is more than 6’ from an outlet (e.g. 12’ spacing between outlets)

CEC 210.52 (B) – Countertop spacing: 12” or wider countertop to be at least (1), no more than 24” from any point along the countertop wall to an outlet (i.e. 4’ between), islands or peninsular countertops more than 24” to have (1).

CEC 210.52(B)(1) – Small appliance branch circuits for kitchen to also serve all dining room wall receptacles and refrigeration outlets (or refrigerator can be on a dedicated 15 Amp or more circuit).

CEC 210.70 (A)(1) – At least (1) wall switched light outlet required in every habitable room and bathroom and hallway, stairway, garage, exterior side of outdoor grade level entrances (garage vehicle doors are exempt)

CEC 406.12 – Tamper resistant receptacle outlets for all non-locking 120V/15 and 20 amp outlets unless for luminaries or over 5.5’ above floor or a single outlet for a single dedicated appliance which is not easily moved or a duplex outlet for (2) dedicated appliances.

150.0(k) – All Kitchen lights to be high efficacy (Exhaust hood lights are EXEMPT).

150.0(k)(1)(c) – Recessed lights – Insulation Contact rating (IC) required, also to be certified Air Tight (AT), and to be sealed or gasketed or caulked between ceiling and light housing.

150.0(k)2(L) – Under cabinet lights to be switched separately from other lights.

150.0(j)2) – R4 (1”) pipe insulation required on all HOT water pipes ¾” or larger to point of use and all HOT water pipes (regardless of size) to kitchen fixtures.  Also first 5’ of hot and cold water pipes at the water heater. Pipe insulation NOT required at framing penetrations.  Pipe in insulated wall cavity is acceptable ONLY if Quality Insulation Installation (QII) standards (HERS verification) are met.  Pipe in attic is exempt IF buried by at least 4” blown insulation.  Pipe Insulation to be 4” min from water heater flue.  Hot and cold water lines should be at least 2” apart (to allow 1” insulation on each pipe).

CGC 4.303.1 – Water Usage: Kitchen faucets: 1.8 gal (SB 407:2.2 gal max) (Note: SB 407, aka: California Civil Code 1101, requires some additions and alterations to retrofit existing noncompliant water fixtures to meet current water saving standards.  Noncompliant is defined as a Kitchen faucet greater than 2.2 gal/min flow rate.

LAUNDRY AREA

CRC R105.2 – Clothes dryers exempt from permits.

CRC R305.1 – Laundry rooms shall have a ceiling height of not less than 6’-8”.

CRC R306.4 – Hot and cold water required to washing machine outlets.

CRC R312.2.1 – When fall from window would be more that 72” to surface below, window sill to be 24” min. above floor OR, if less than 24” above floor, window opening shall not allow the passage of a 4” diameter sphere or other device to other approved opening control device.

CPC 507.5 – Drainage pan under water heater if: in attic, on attic-ceiling or floor-ceiling or floor-subfloor where damage could result from leakage.  ¾” minimum drainage line to approved location.  Pan to be 1.5” in depth.

CPC 608.5 – Temperature & Pressure (T & P) relief valve to discharge through an air gap to a drainage system or to the outside of the building between 6” – 24” above grade and pointing downward without threads on the termination pipe.  Not allowed to discharge into a water heater drain pan. 

CPC 804.1 – Clothes washer stand pipe limited to between 18” – 30” above trap.  Trap to be between 6” – 18” above floor.

CMC 504.4 – Domestic type (Type 1) clothes dryer ducts shall NOT be connected with screws or other fasteners that extend into the duct, and shall terminate outside with a backdraft damper and where joining ducts, the male end shall be inserted in the direction of airflow.

CMC 504.3 – Clothes dryer ducts shall NOT extend through plenums or ducts (CAN’T FIND IN 2016 CODE)

CMC 504.2.2 - Domestic type (Type 1) clothes dryer ducts shall be a minimum of 4” in diameter.  The exhaust duct shall not exceed a total combined horizontal and vertical length of 14 feet, including two 90 degree elbows.  Two feet shall be deducted for each 90 degree elbow in excess of two.

CMC Section 504.4.1 - Clothes dryer to be provided with make-up air in accordance with manufacturer’s specifications.

CMC Section 504.4.1 - Where a closet is designed for the installation of a clothes dryer, an opening of not less than 100 square inches for makeup air shall be provided in the door or by other approved means. 

CEC 210.8(A)(10) – All 125 volt, 15 and 20 amp receptacle outlets in Laundry area to be GFCI protected.

CEC 210.11(C)(2) – At least (1) 20 amp branch circuit required for laundry receptacle outlet(s) – no other outlets allowed on this circuit.

CEC 210.12(A)Arc-fault circuit interrupter required for outlets in most rooms of house, including laundry areas (except: bathrooms, garages, non-habitable attics, unfinished basements, and exterior outlets).

CEC 210.12(B)AFCI circuits wire length limited from AFCI breaker to first receptacle outlet or AFCI receptacle to next receptacle outlet is 50’ maximum for #14 wire and 70’ for #12 wire.  The first AFCI outlet to be marked as such (i.e. “First AFCI Outlet”).

CEC 210.52(A) – General convenience receptacle outlet requirements (12’ spacing) NOT applicable in laundry rooms (UNLESS you consider the “or similar room or area” language to apply).

CEC 210.52(F) - Provide at least one receptacle outlet for the laundry equipment.

CEC 210.70 (A)(1) – At least (1) wall switched light outlet required in every habitable room and bathroom and hallway, stairway, garage, exterior side of outdoor grade level entrances (garage vehicle doors are exempt).

CEC 406.12 – Tamper resistant receptacle outlets for all non-locking 120V/15 and 20 amp outlets unless for luminaries or over 5.5’ above floor or a single outlet for a single dedicated appliance which is not easily moved or a duplex outlet for (2) dedicated appliances.

150.0(k) – All lighting to be high-efficacy.

150.0(k) – Laundry to have at least (1) high efficacy light fixture controlled by a vacancy sensor.

150.0(j)2) – R4 (1”) pipe insulation required on all HOT water pipes ¾” or larger to point of use and all HOT water pipes (regardless of size) to kitchen fixtures.  Also first 5’ of hot and cold water pipes at the water heater. Pipe insulation NOT required at framing penetrations.  Pipe in insulated wall cavity is acceptable ONLY if Quality Insulation Installation (QII) standards (HERS verification) are met.  Pipe in attic is exempt IF buried by at least 4” blown insulation.  Pipe Insulation to be 4” min from water heater flue.  Hot and cold water lines should be at least 2” apart (to allow 1” insulation on each pipe).

150.0(o) – ASHRAE 62.2 – Laundry rooms must be built with a duct to the outdoors, to be connected to the clothes dryer.  Warm moist air from clothes dryer is prohibited from being used in the home for heating purposes (some cold climates like this warm/moist air to be used in the home – but it is prohibited by the ASHRAE standards because of the dust in the exhaust air).

LIVING ROOM (see FRONT ROOM)

MUD ROOM (aka UTILITY ROOM, MECHANICAL CLOSET)

CRC R305.1 – Minimum ceiling height 7’-0”.

CRC R306.4 – Hot and cold water required to washing machine outlets.

CRC R312.2.1 – When fall from window would be more that 72” to surface below, window sill to be 24” min. above floor OR, if less than 24” above floor, window opening shall not allow the passage of a 4” diameter sphere or other device to other approved opening control device.

CRC R313.3.1.2 Exception 4 – AFES not required in unheated entry areas (such as mud rooms) adjacent to an exterior door.

FAU and Water heater requirements

CEC 210.12(A)Arc-fault circuit interrupter required for outlets in most rooms of house (except: bathrooms, garages, non-habitable attics, unfinished basements, and exterior outlets).

CEC 210.12(B)AFCI circuits wire length limited from AFCI breaker to first receptacle outlet or AFCI receptacle to next receptacle outlet is 50’ maximum for #14 wire and 70’ for #12 wire.  The first AFCI outlet to be marked as such (i.e. “First AFCI Outlet”).

CEC 210.70 (A)(1) – At least (1) wall switched light outlet required in every habitable room and bathroom and hallway, stairway, garage, exterior side of outdoor grade level entrances (garage vehicle doors are exempt).

CEC 406.12 – Tamper resistant receptacle outlets for all non-locking 120V/15 and 20 amp outlets unless for luminaries or over 5.5’ above floor or a single outlet for a single dedicated appliance which is not easily moved or a duplex outlet for (2) dedicated appliances.

150.0(k) – All lighting to be high-efficacy.

PATIO, PATIO ENCLOSURE, SUNROOM, PORCH

CRC R301.2.1.1.1 – Sunrooms to comply with AAMA/NPEA/NSA 2100-12 standards.  These standards are different than CRC Appendix H requirements.

CRC R303.1 Ex #3 – Natural ventilation from patios and sunrooms can be used in adjoining rooms if more than 40% of the exterior walls are open or enclosed only with insect screen.

CRC R303.2 Exception – Opening for Light and ventilation from patio to be 20 Sq. Ft. min (openable) or 10% (openable) of floor area of room.

CRC R303.8.1 - Required windows may open onto patio or sunroom as long as ceiling is at least 7’ tall and 40% min. of sunroom walls are open (or insect screening).

CRC R312.2.1 – When fall from window would be more that 72” to surface below, window sill to be 24” min. above floor OR, if less than 24” above floor, window opening shall not allow the passage of a 4” diameter sphere or other device to other approved opening control device.

CRC R313.3.1.2 Exception 4 – AFES not required in open attached porches.

CRC R337.7.6 - The exposed underside of exterior porch ceilings in designated Fire Hazard Severity Zones shall be protected by specified noncombustible or ignition resistant materials. 

CRC Appendix H – Patio Enclosures - AH103.1 – Longer wall plus one additional wall to be 65% open or glazed below 6’-8” (glass, insect screen, translucent plastic are OK).

CRC Appendix H – Patio Enclosures - AH103.2 – Bedroom windows – Patio covers over bedroom egress windows to be unenclosed.

CRC Appendix H (AH103.1) – Patio enclosure glass (in enclosure walls) to be tempered IF required by CRC R308 (Safety glass is required if in a hazardous location.  One example where safety glass is required is where the glass meets ALL of the following criteria: one exposed pane is greater than 9 square feet AND the bottom edge of the glass is less than 18” above floor AND the top edge of glass is more than 36” above the floor AND there are walking surfaces within 36” horizontally of the glass – there are a few exceptions see R308.4.3)

CEC 210.8(A)(3) – GFCI outlets required outdoors.

CEC 210.52(E)(1) – At least (1) receptacle outlet required at front and (1) at rear of house.  Not more than 6.5’ above grade level.

CEC 210.52 (E)(3) – Balconies, decks and porches to have at least one receptacle outlet if deck is attached to dwelling AND access to balcony is from within the dwelling (Max. height of outlet is 6.5’ above deck).

CEC 210.70 (A)(1) – At least (1) wall switched light outlet required in every habitable room and bathroom and hallway, stairway, garage, exterior side of outdoor grade level entrances (garage vehicle doors are exempt).

CEC 406.9 (A) & (B) – Outdoor receptacle outlets to be weatherproof covered with the chord/plug in if in wet location (w/o plug in if in damp location).  Damp location is protected from rain by roof (i.e. under patio cover).

CEC 406.12 – Tamper resistant receptacle outlets for all non-locking 120V/15 and 20 amp outlets unless for luminaries or over 5.5’ above floor or a single outlet for a single dedicated appliance which is not easily moved or a duplex outlet for (2) dedicated appliances.

CRC R313.3.2.4.2.1 – Pendent sprinkler heads to be no closer than 3’ to the center of ceiling fan or ceiling mounted light fixture.

CEC 314.27 (C) – Paddle fan support boxes to be labeled for such use.

150.0(k)Outdoor lighting must be high-efficacy AND have motion sensor plus photocell or astronomical time clock AND a manual On/Off switch that does not override the automatic controls.

This is a TEST…

What’s wrong with this picture?

This is a 200 amp electrical service panel for a new single family dwelling. Forget about the solar stuff, and the ufer access (it is on the other side of the wall). There is something else missing. (Hint: The topic was discussed in a previous edition of the Willdan Letter.)

If you can identify the problem, please send me an email at: dchudy@willdan.com and tell me what you see.

The first respondent with the correct answer will be acknowledged in the next issue of the Willdan Letter. 

Good luck.

200-amp electrical panel

Results from Last Issue's Test

In the last issue, we asked readers to email responses to this question: “What’s wrong with this picture?”

dryer duct termination

The first person to correctly identify the problem was Johnathan R. Hurst, Building Official for the City of Arroyo Grande, California.  Johnathan correctly identified that the dryer duct termination (shown behind the air conditioning condenser) is not the required 5’ from the condenser, which was discussed in an article in issue #54 of the Willdan Letter.  (Section 150.0(h)3(A) of the 2016 California Energy Code states that a minimum 5’ clearance is required between the air conditioner or heat pump outdoor condensing units and dryer vent outlets.) 

There were also numerous other respondents who not only identified that the dryer duct termination was in violation but that there were multiple other violations.  Below are some of the other violations which were identified by readers:

  • Liquid tight flex conduit is not secured within 12" from disconnect.
  • UV protection not provided over line set insulation.
  • 30" wide clearance not provided in from of disconnect.
  • Possible clearance issues to the rear of the condenser unit depending on the manufacturer.
  • Possibly no refrigerant port locks.
  • Condenser possibly not secured in place on pad.
  • Refrigerant line may be in contact with wall jack (dissimilar metals).

Thanks to ALL of those who emailed responses to the “TEST” question.

Habitat for Humanity Hurricane Relief

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Willdan made the pledged donation to Habitat's hurricane relief fund so it could bring immediate aid to victims of Hurricanes Harvey, Irma and Maria.

LEGISLATIVE REVIEW

For a list of legislative actions which may have an impact on local building departments, visit the CALBO Legislative Watch page.