Electrical System Defects List & Home Inspection Education
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Electrical system inspection recommendations
Electrical system defects list: residential, light commercial
Lists of important defects for residential buildings
What does a home inspector need to know? Home inspection training and education curriculum recommendations

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This article lists significant Electrical System defects, definitions, and home inspection education topics. This article series, beginning at BUILDING DEFECTS LISTS, provides lists of common building defects and basic defect knowledge that also outline recommended curriculum content for home inspector education. The building defects and inspection points listed in these articles also guide homeowners and home buyers to building areas that merit careful attention and often point areas of safety concern or important maintenance and repair tasks.

Readers should see ELECTRICAL INSPECTION, DIAGNOSIS, REPAIR for our complete list of articles on this topic. Also see HOME & BUILDING INSPECTORS & INSPECTION METHODS. Use the Search Box at the top or bottom of these pages to find in-depth information about building, energy savings, and indoor environment inspection, diagnosis and repair at this website. Watch out: these inspection lists do not list all possible defects for the systems discussed, and not all home or building inspectors will examine all of the items listed here. CONTACT us to suggest corrections or additions to articles at this website.

Also see these related article groups:
ALUMINUM WIRING HAZARDS
DEFINITIONS of ELECTRICAL TERMS
FEDERAL PACIFIC FPE HAZARDS
ELECTRICAL GROUND SYSTEM INSPECTION
GFCI PROTECTION,Testing GFCIs AFCIs
KNOB & TUBE WIRING

LIGHTING, EXTERIOR GUIDE
LIGHTING, INTERIOR GUIDE
LIGHTNING PROTECTION SYSTEMS
LOW VOLTAGE BUILDING WIRING
MAIN DISCONNECT
SAFETY for ELECTRICAL INSPECTORS
ZINSCO / SYLVANIA HAZARDS

These curriculae and building defect lists are based on smilar curriculum documents first prepared by Joe Scaduto, an ASHI member who prepared course material for Northeastern University's Building Inspection Certificate program in 1988, subsequently by DF, InspectApedia's editor, for New York University ca 1988 and later, with others, recommended to ASHI, the American Society of Home Inspectors. ASHI did not adopt this material though currently that association as well as others offer extensive HOME INSPECTOR EDUCATION material. The curriculum and lists of defects are informed by additional analysis of the process of home inspection that was developed beginning Calgary, AB for Canadian and U.S. home inspector education and certification examinations in 1997. Other early contributors to home inspection education in the U.S. and Canada include Dr. Jess Aronstein, Alan Carson, Mike Casey, Mark Cramer, John Cox, Dwight Barnett, Douglas Hansen, Rick Heyl, Larry Hoytt, Bill Merrill, Kevin O'Malley, Dennis Robitalille, Keith Peddie, Pat Porzio, Roger Robinson.

© Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

Home Inspection Education Curriculum - Electrical

3.0 ELECTRICAL System Inspection Requirements & Defects List

3.1 Service Drop and Service Entrance

3.1.1 Knowledge Base

1. Describe the function of the electrical system in the home.

2. Describe the location and function of the service drop and service entrance.

3. Describe two types of service drops (overhead and underground).

4. Describe two types of service entrance (conduit and cable).

5. List the common materials used for service entrance conductors (copper, aluminum).

6. Describe the features of adequate installation and repair technique for service drops and service entrance conduit or cable.

7. Define the following terms:

service drop, service lateral, service entrance conductor, over-current device (over-current protection device), amp (amperes), volt (voltage), electrical potential (electromotive force), ohms (resistance), ungrounded conductor (black, hot, red, hot), grounded conductor (white, neutral, identified conductor), grounding conductor (green, bare, ground), bonding conductor, alternating current versus direct current, insulator versus conductor, 120 versus 240 volts, impedance, resistor, watt, kilowatt, kilowatt-hour ( kWh), electrical circuit, short circuit, fuse, breaker, ground fault, overload, parallel circuit, series circuit, drip loop, masthead (service cap, entrance cap, pothead?? Not home inspectors!, weather head, service head), three phase electrical system (does three phase matter to home inspectors?)On rare occasions these can be found. JDG\, service capacity, service panel, distribution panel, combination panel.

8. Write the formula for voltage as a function of current and resistance. Write the formula for power as a function of voltage and current, and be able to rearrange both formulas to solve for any variable. This is really not required to be a home inspector, but the RDS includes theory Conversion fomula for KW to BTU..JDG

9. Understand the term load calculation with respect to sizing house electrical services (performing load calculations is not part of a home inspection).

10. Identify the codes and standards which apply to electrical service drop and service entrance in your area.

3.1.2 Inspection Skills:

1. Describe the inspection procedure for service drop and service entrance systems.

2. Describe the procedure for identifying service capacity and evaluating service adequacy.

3. Identify the common defects listed on the next page.

4. Describe the implication of each of the defects above.

5. Identify the safety issues for the inspector and the occupant of the house (electrical shock, fire).

6. Communicate findings to client verbally and in writing, recommending corrective action where needed.

ELECTRICAL SERVICE DROP AND SERVICE ENTRANCE TYPICAL DEFECTS

SERVICE DROPS OR SERVICE LATERALS SERVICE CAPACITY

• Branches, vines interfering with wires • Fuse, breaker size in service box

• Damaged, frayed wires • Inadequate service size

• Excessive height • Marginal service size

• Clearance over roofs • Rating of service box

• Clearance over walking areas • Service conductor size

• Clearance over roadways

• Clearance over driveways

• Clearance over decks, balconies and pools

• Inadequate window or door clearance

• Poor connection to service conductors

SERVICE CONDUCTORS OR SERVICE

ENTRANCE WIRES

• Conduit or cable damaged

• Conduit or cable covered by siding or roof penetrations for additions. JDG

• Conduit or cable not weathertight

• Drip loop too low (touching roof)

• Mast rust

• Mast bent

• Mast rot

• Mast loose

• Mast not weathertight

• Masthead not weathertight

• No masthead

• No drip loop

• Wires too close to roof

3.2 Service Panel, Grounding and Panels

3.2.1 Knowledge Base

1. Describe the function of the service panel

2. Describe the function of the grounding system.

3. Describe the function of distribution panels.

4. Describe three types of service panels (fuse, breaker, combination).

5. List the materials and components of service panels.

6. Describe the features of adequate installation and repair techniques for service boxes.

7. Describe the materials and components of an electrical grounding system.

8. Describe the features of adequate installation and repair techniques for house grounding systems including systems that terminate at ? water pipes, metal rods in ground, UFER ground (concrete encased grounding electrode), grounding plates or rings, metal building frames, well casings.

9. Describe the types of distribution panels (fuses, breakers, combination).

10. List the typical materials and components of distribution panels.

11. Differentiate between main distribution panels and sub-panels.

12. Describe the features of good installation and repair techniques for main and sub-panels.

13. Define the following terms:

Service box (service equipment, main panel, service panel these are all the same to me??), distribution panel, combination panel, grounding equipment, over-current device, electrical meter, line and load, carrier current controller, bonding, dielectric connector, type S fuse, type D fuse, type P fuse, distribution panel (service panel, , subpanel, fuse box, fuse panel, , ), pull-out fuse box, overfusing, cartridge fuse, fused neutral, double tap (double lugging), pig tailing, multi-wire branch circuit, bus bar, linked fuse, linked breaker, single throw and double throw breaker, single pole and double pole breaker.

14. When is a service panel not required?

15. Identify the codes or standards which apply to electrical service boxes, grounding systems and panels in your area.

3.2.2 Inspection Skills:

1. Describe the inspection procedure for:

the service panel

grounding system

auxiliary panels

2. Identify the common defects listed on the next page.

3. Describe the implication of each defect.

4. Identify the safety issues for the inspector and occupant of the house (electrical shock, fire).

5. Communicate findings to client verbally and in writing, recommending corrective action where needed.

Electrical SERVICES BOX, GROUNDING AND PANEL TYPICAL DEFECTS

SERVICE PANEL DISTRIBUTION PANELS

• rating too small • Circuits not labeled

• location improper • Damaged panel or components

• not weathertight • Double taps

• Damaged parts • Fuse holder loose or broken

• Fused neutral • Fused neutrals

• Fuses upstream of disconnect switch • Fuses loose

• Improper taps • Fuses or breakers too big

• Inappropriate mounting surface • Fuses bypassed

• Multiple disconnects • Inappropriate mounting surface

• Neutral wire bypasses service • Loose breakers

• Not well secured • Loose or missing door

• Obsolete service box • Loose panel

• Overheating • Multi-wire circuit on same bus

• Poor access • Neutral and ground wires bonded at subpanel

• Poor connections • No fuses or breakers for subpanel and feeder

• Rust Corrosion JDG • No links for multi-wire circuits (only required if they terminate at the same device)

• Service entrance wires exposed in house • Not rated for aluminum

• Single main disconnect ?? isn’t one disc. OK? • Obsolete

• Unprotected openings • Openings in panel

• Wrong fuse or breaker size or brand • Overheating

• Panel crowded

• Panel upside-down

• Rust Corrosion. JDGor water in panel

• Subpanel not grounded

• Undersized panel

• Wrong fuses or breakers for subpanel and feeder

• Wrong breaker for panel

Electrical SYSTEM GROUNDING Defects List

• Box not bonded to ground

• Connections not accessible

• Corroded grounding conductor

• Grounding electrode rod cut or disconnected..JDG

• Missing

• Neutral bonded to grounding conductor wire

downstream of service box

• Neutral not bonded to ground at box

• No jumper for meters and valves WIRES

• No ground for subpanel

• Poor connections • Abandoned wires in panel

• Spliced grounding conductor wire • Damaged

• Undersized grounding conductor wire • Loose connections

• Wire attached to plastic pipe • Not well secured

• Wire attached to abandoned pipe • Overheating

• Sheathing not removed

• Wire crossing bus connections

3.3 The Electrical Distribution System - Wiring Defects

3.3.1 Knowledge Base

1. Describe the function of the electrical distribution system in a house.

2. List the materials and components of the distribution system including the common conductor types (conventional copper, aluminum and knob-and-tube).

3. Describe the features of adequate installation and repair technique for the distribution system including wiring, lights, outlets, switches, and junction boxes.

4. Define the following terms: branch circuit conductor, polarity, ground fault circuit interrupter, NMW cable, NMD cable, BX cable, solder-dipped wire, wire insulation versus sheathing , solid and stranded wire (including typical sizes for each), wire gauge (including AWG and MCM), dedicated circuits, anti-oxidant, CuAl JDG, CO/ALR, COPALUM, wire nut, (solderless connector, twist-on connector), creep with respect to aluminum wire, potlight (recessed light fixture, high-hat light fixture), three way switch, four way switch, two-pin receptacle, three-pin receptacle.

5. Identify the codes or standards which apply to the electrical distribution system in your area.

3.3.2 Inspection Skills:

1. Describe the inspection procedure for the distribution system including the conductors, lights, outlets, switches and junction boxes, including central air-conditioner circuits.

2. Describe the special inspection issues related to aluminum wiring.

3. Identify the common defects listed on the next page.

4. Describe the implication of each defect .

5. Identify the safety issues for the inspector and the occupant of the house(electric shock and fire).

6. Communicate findings to client verbally and in writing, recommending corrective action where needed.

Electrical DISTRIBUTION SYSTEM, Wiring, Receptacles, Lights & Fixtures, TYPICAL DEFECTS

WIRING LIGHTS

• Abandoned wire • Damaged

• Buried cable • Heat lamps over doors

• Damaged • Improper closet lighting

• Exposed on walls or ceilings • Improper spotlights ? JDG

• Exposed in attics • Inoperative nonresponsive ? JDG

• Isolating links needed on pull chains wiring

• Improper color coding • Loose

• In steel studs without protection • Not grounded

• Indoor cable used outdoors • Obsolete

• Loose connections • Overheating

• Missing • Poor stairway lighting

• Not well secured Lights needed at exterior doors

• Open splices Electrical SWITCHE Defects

• Overhead wires not stranded

• Permanent wiring used as extension cord • Damaged, loose, rust

• Too close to ducts, pipes, chimneys, etc. • Faulty 3-way dimmer switch

• Too close to edge of studs or joists • Inoperative, obsolete

• Under carpets • No shut off

• Undersized wire • Overheated

• Wrong type • Poor location in bathroom

• Poor garbage disposal switch location

KNOB-AND-TUBE • Poor location at furnace

• Buried in insulation JUNCTION BOX Defects

• Connections need boxes

• Conventional lights in wet areas • Concealed boxes

• Fused neutrals • Cover loose or missing

• Wire insulation or sheathing brittle • Damaged, rust

• Missing, loose

ALUMINUM • Not grounded

• Overcrowded

• Connectors not compatible with • Overheating

aluminum

• No grease on stranded wires OUTLETS

• Overheating

• Above electric baseboard heaters

OUTDOOR WIRING • Broken pin or blade in slots

• Damaged

• Buried wire • Dedicated circuits needed

• Extension cords powering exterior outlets • In floors or countertops

• Garage door opener connected to • Inoperative

extension cord

• Indoor wire used outdoors • Loose

• Not suitable for use • No GFI

• Solid wire run overhead • Open neutral

• Wires not well secured to walls • Open hot

• Wires too close to grade • Overheated neutral

• Wires run on roof surfaces • Overheating

• Wires through gutters or downspouts • Reverse polarity

• Too close to bathtubs

• Too few outlets

• Too far from basin

• Ungrounded

• Within 18 inches of garage floor

• Worn receptacles

• Wrong type

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Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. Thanks to Alan Carson and Bob Dunlop, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education including the ASHI-adopted Home Inspection Training Program (home study course), publications such as the Home Reference Book, report writing materials including the Horizon report writer, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. Contact Mark Cramer at: 727-595-4211 mark@BestTampaInspector.com 11/06
Roger Hankey is principal of Hankey and Brown home inspectors, Eden Prairie, MN. Mr. Hankey is a past chairman of the ASHI Standards Committee. Mr. Hankey has served in other ASHI professional and leadership roles. Contact Roger Hankey at: 952 829-0044 - rhankey@hankeyandbrown.com. Mr. Hankey is a frequent contributor to InspectAPedia.com.
Arlene Puentes, an ASHI member and a licensed home inspector in Kingston, NY, and has served on ASHI national committees as well as HVASHI Chapter President. Ms. Puentes can be contacted at ap@octoberhome.com
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Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.

The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 2010, $69.00 U.S., is available from Carson Dunlop. The Home Reference Book is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. InspectAPedia.com ^® author/editor Daniel Friedman is a contributing author. Field inspection worksheets are included at the back of the volume.

ASHI Certification Links
Home Inspection Reports - a Critique narrative vs. checklist type home inspection reports
ASHI Standards of Practice - Jan 2000 and ASHI Standards History - links to older and alternative versions of Home Inspection Standards
ASHI Code of Ethics 1993, and ASHI Ethics History - links to older versions; Note: newer may be found at ASHI
ASHI in 1996 ASHI History - association description from 1996
American Society of Home Inspectors (ASHI) Official Website
Basement Moisture Control, U.S. Department of Energy
Building Pathology, Deterioration, Diagnostics, and Intervention, Samuel Y. Harris, P.E., AIA, Esq., ISBN 0-471-33172-4, John Wiley & Sons, 2001 [General building science-DF] ISBN-10: 0471331724 ISBN-13: 978-0471331728
Building Pathology: Principles and Practice, David Watt, Wiley-Blackwell; 2 edition (March 7, 2008) ISBN-10: 1405161035 ISBN-13: 978-1405161039
Building inspection education & report writing systems from Carson, Dunlop & Associates Ltd
Crawl Space Moisture Control, U.S. Department of Energy
Historic Preservation Technology: A Primer, Robert A. Young, Wiley (March 21, 2008) ISBN-10: 0471788368 ISBN-13: 978-0471788362
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Home Inspection Education Curriculum - Electrical

3.0 ELECTRICAL System Inspection Requirements & Defects List

ELECTRICAL SERVICE DROP AND SERVICE ENTRANCE TYPICAL DEFECTS

Electrical SERVICES BOX, GROUNDING AND PANEL TYPICAL DEFECTS

Electrical SYSTEM GROUNDING Defects List

3.3 The Electrical Distribution System - Wiring Defects

Electrical DISTRIBUTION SYSTEM, Wiring, Receptacles, Lights & Fixtures, TYPICAL DEFECTS

Questions & Answers regarding this article

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Technical Reviewers & References

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair