This page contains limited information regarding circuit installation and wiring. Additional information is needed to properly install wiring. Circuit installation and wiring require knowledge and expertise to maintain electrical safety. When in doubt installations should be performed by professionals. All electrical work shall comply with the adopted Electrical Code.
Clearances and Access to Electrical Panels
Equipment shall not be installed in front of electrical panels. Electrical panels shall not be installed in storage closets or bathrooms, and closets or bathrooms should not be built around existing electrical panels.
- Bathroom receptacles – One separate 20 amp circuit, receptacles shall be GFCI protected.
- Laundry area – One separate 20 amp circuit.
- Kitchens – Two separate 20 amp circuits for the counter top. Counter top receptacles shall be GFCI protected.
Note: Separate circuits may be required for other appliances based on the manufacturer’s installation instructions. A separate circuit for large appliances, such as dishwashers, space heaters, etc… may also be required.
Switch controlled lighting
- At least one wall switch-controlled light fixture must be installed in every habitable room and bathroom. In other than kitchens and bathrooms one or more receptacles controlled by a wall switch shall be substituted for the lighting outlet.
- A wall switch-controlled lighting fixture must be installed in hallways.
- Lighting for stairways shall have wall switch-controls at each floor level
All splices for wiring must be made within approved outlet boxes or junction boxes that are readily accessible for inspection and repair.
- Do not install junction boxes in the attic or conceal them within walls.
- Make sure all boxes are correctly sized for the number or wires entering and exiting the boxes.
To simplify installations purchase outlet boxes with the largest volume compatible with the type of fixture being used.
As a general rule, plan your wiring to receptacles in a continuous series, and avoid using the boxes for dual purposes such as having the box serve receptacles and as a junction box to branch in more than one direction. For homeowners doing their own work selecting a box with that volume of space for the type of receptacle being installed is advisable. Boxes are sized by assigning a minimum volume to each conductor entering and exiting the boxes and for each device in the box. To read more about Code Calculations.
Finishing your basement triggers a requirement to upgrade the smoke detectors throughout your home to new dwelling standards. Smoke detectors are required in each sleeping area, outside of each sleeping area and on each story of the dwelling. Detectors shall receive their primary power from the house wiring and shall be provided with battery backup. The detectors shall be interconnected so that the activation of one detector will activate all of the connected devices. An exception to this requirement allows battery operated smoke detectors to be added where finish materials have not been removed in areas requiring the upgrade, and there is no attic space or other access that would allow the detectors to be hard wired and tied together.
(GFCI) Ground fault circuit interrupter protected of outlets
GFCI protection for receptacles is required in the following locations:
Unfinished basement areas (areas used as work rooms, storage and mechanical equipment) – Note: Dedicated circuits for a washer, dryer, furnace, sump pump, refrigerator or freezer do not require GFCI protection.
- Receptacles serving bar sinks, sinks, kitchen counter top and kitchen islands.
(AFCI) Arc fault circuit interrupter protected outlets
The Electrical Code has added arc-fault circuit interrupter protection requirements for all electrical outlets in bedrooms. AFCI protects against arcing that may occur in broken or frayed cords of electrical appliances. AFCI protection is either installed at the circuit breaker or an AFCI outlet is installed on the first receptacle in the series.
Receptacle outlet spacing – Note: All receptacles shall be of the grounding type.
- General use outlets (bedrooms, kitchens, family rooms, dens, sunrooms, recreation rooms and similar spaces) – Receptacles shall be provided for all unbroken wall spaces over 2 feet wide; Receptacles shall be located so that no point on the floor line is more than 6 feet, measured horizontally from an outlet.
- Kitchens and counter tops – one receptacle for each wall space wider than 12 inches; no space along the wall shall be more than 24 inches from a receptacle; at islands or peninsula counters provide one receptacle when the counter has a long dimension more the 24 inches or a short dimension more than 12 inches.
- Bathrooms – Provide one receptacle for each bathroom within 3 feet of the outside edge of each lavatory/sink.
- Hallways – Hallways of 10 feet or more in length shall have at least one receptacle.
Where ceiling heights are less than 7 feet above the floor recessed fixtures should be used to minimize damage to fixtures and potential fire and safety hazards.
In closets and storage spaces care should be taken to assure lighting fixtures do not come in contact with combustible materials. Surface mounted incandescent lighting fixtures (including pendant fixtures) shall provide a minimum 12 inches of clearance from the front of shelves and any point where storage can occur. The clearance can be reduced to 6 inches for recessed and/or fluorescent fixtures.
Bar areas, kitchenettes and kitchens
Where a full kitchen is installed it shall be wired to meet the requirements of a kitchen. Where a secondary space, like a bar, is designed to serve as a space for small cooking appliances such as pop corn poppers, coffee makers, ice makers, microwave, blenders, etc.., the space should also be provided with circuits as if the space was a kitchen; however, the code does not mandate that this be done. It only addresses “kitchens”.
To wire the kitchenette to meet the requirements for kitchens provide:
- Two 20-amp small appliance circuits to serve the countertop receptacles – GFCI protection required.
- Receptacle required for each counter space wider than 12 inches.
- Receptacles shall be spaced so no counter space is more than 24 inches measured horizontally along the wall or counter edge from a receptacle.
- 15- or 20- amp circuits to serve individual appliances (it is not recommended that these be provided with GFCI protection)
- 20-amp circuit for dishwasher
- Garbage disposal circuit
Common Electrical Requirements That Get Overlooked:
- ALWAYS follow the manufacturer’s installation instructions.
- Everything metallic that is part of the electrical circuit should be properly bonded to the equipment grounding conductor (the bare or green wire).
- Attach junction boxes to studs so that the edge of the box will end up flush with the sheetrock.
- All connections for wiring shall be within approved electrical boxes. All junction boxes shall remain accessible and shall not be concealed within walls or ceilings.
- The gap between the edge of the junction box and the sheetrock should be no larger than 1/8 inch.
- Access to the grounding electrode conductor (large bare copper wire) connection to the water line must be provide/maintained.
- Properly label new circuits in the breaker panel box.
- Electrical conductors (wires) are required to be properly color coded. The most common coding is white is for the grounded conductor (neutral), green is for the equipment grounding conductor, and black or red for the ungrounded (hot) conductor.
- The maximum size of breaker to protect the circuit conductors is 15 amps for #14 gauge conductors, 20 amp for #12 gauge conductors, and 30 amps for #10 gauge conductors.
- Do not mix conductor sizes on a single circuit.
- Normally, only one conductor is allowed under each screw on the breaker.
- Switches and outlets (plugs) must be securely fastened to the junction box, and covered with a compatible cover.
- GFCI protection is required for receptacles in unfinished portions of the basement.
- A cover is required for all junction boxes.
- Breaker boxes are not allowed in closets or bathrooms.