Safety

Ask the Electrician: Knob and Tube Wiring

Q: What is Knob & Tube Wiring?

Knob and Tube refers to a type of wiring commonly used from the late 1800’s until the 1940’s. At the time it was cost effective and appropriate for the electrical systems of most homes. It is still found in many older homes today. 

Knob and Tube Components:

  • Wire: K&T uses copper wire but only consists of a hot and a neutral strand. Commonly it is 14 gauge and supported a maximum of 15amps. Homes were often wired with a single circuit for the entire house that did lights and few or no receptacles. As electrical needs grew and plug-in appliances became more commonplace, knob and tube wiring became obsolete by the mid 1940’s.

  • Knob: Circular Porcelain disks with a center nail hole are attached to framing to hold the wire in place or allow it to wrap around and change direction. These “knobs” hold the wire away from any wooden structures and allow it to dissipate heat and insulate it from touching flammable surfaces.

  • Tube: Porcelain tubes are placed where wires need to go through joists or framing structures. These insulate the wire from the flammable wood.

  • Loom: Wires are wrapped in a flexible fabric or rubber casing to insulate and protect them. This was often cotton coated in asphalt or even asbestos. This served to protect the wire especially where it went behind wall spaces or attached to fixtures.

Is K&T dangerous?

Knob and Tube wasn’t inherently dangerous when it was installed but is obsolete and no longer allowed for modern construction. It should be replaced for several reasons:

  • The biggest concern with K&T systems is the lack of a ground wire. This presents a shock hazard and needs to be addressed from a safety standpoint.

  • This lack of ground is especially problematic for bathrooms and kitchen areas that require GFCI/AFCI protection or appliances requiring a three prong plug.  These areas are often modified to try to accommodate modern standards.

  • Modern homes have higher electrical needs so face limitations in amperage for newer appliances and additional outlets and receptacles.

  • Modern layouts use more intricate circuits, often with multiple branches to route electricity to more outlets and appliances. Many knob and tube systems wired the entire home through a single looped circuit.

  • K&T systems can pose fire hazards when trying to insulate around them. Modern blown-in insulation is especially an issue as materials can touch uninsulated wires or allow heat to build up. 

  • The loom materials often become brittle and crack with age, exposing live wires. Additionally, the cloth can be attractive to rodents and other pests and invite chewing. Loom materials are often not rated for exposure to moisture, so damp areas like crawl spaces can be an extra hazard.

  • By nature K&T is more rigid; wires are bent by a “knob” so offer less flexibility than modern Romex.  Modern wiring has better flexibility to be fed through walls and throughout the home safely.

  • Standards for splicing wires together have changed, K&T required hard splicing but allowed for these to be wrapped or hidden, modern code requires a junction box that is accessible & visible. These hidden splices are often wrapped in plastic tape and are a fire hazard.

  • Knob and Tube systems are very likely to have had modifications made over the years to help them adapt to new requirements, these updates often create additional shock hazards or unsuspected dangers.

  • Insurance companies may refuse to insure homes with Knob and Tube Wiring or may have higher premiums for coverage.

What should I do if I have knob and tube wiring in my home?

A first step is to have an electrician check if it is still in use and how widespread it is throughout the home. It is common that knob and tube may be disconnected but left in place or that it may have been partially replaced as renovations and upgrades have been done. It is important to assess both conditions:

  • Disconnected but Left Behind: Most often this is a time saving measure to not remove the old K&T wiring. Unless it is being left in place to avoid extensive damage to the home, it is always best to remove old wiring. It prevents any accidental reconnection to a circuit or eliminates any missed connection that might still allow for a live circuit.

  • Mixed Systems: These are common, especially if part of the home has been renovated or an addition has been added over the years. Larger appliances and HVAC systems may have been upgraded because they require a thicker gauge wire but lighting and regular outlets may remain Knob & Tube.  Almost any modification or mixing or new and old systems can create problems.

Takeaway:

If you have Knob and Tube wiring ideally it should be replaced, this addresses any safety issues and provides a modern upgrade to the entire system. Rewiring the entire house can be an expensive project but actual costs will depend on the layout of the home itself. Costs often depend on how easily wiring can be accessed or how much drywall and interior structures need to be removed versus if new wires can be fished through existing walls.

More commonly, we find homes that have partial knob and tube systems still in place so these may not require a full rewire. If you suspect you have knob and tube wiring in your home, give us a call and we can start with an estimate to assess options and determine next steps.

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Older Wiring and Modern Updates

Ask the Electrician: Electrical Panel Maintenance

Q: Does my electrical panel need service or maintenance?

Most homeowners are aware that breakers and/or fuses sometimes wear out and need to be replaced but do not think about the electrical panel itself.  Your electrical panel acts as the transfer point for power coming into your home from the electric company and being distributed to the various circuits and wires in your home. It is also where incoming power is either split or combined to create 120v or 220v for use on these circuits as well as being properly grounded and protected.

The panel components themselves are mostly hardware components, they consist of connections between power coming in and bus bars, neutral or ground terminals and wiring within the “box” to connect and distribute electricity to breakers and then out to the wiring in your home. Wire connections and screws to bus bars and other hardware can simply wear out, corrode, distort or loosen over time and require replacement.

Panel Age:

Like everything else your electrical panel has an expected lifespan.  In general, an electrical panel is good for about 30 years but can last up to 50 years. This means if your home was built before 1990, your panel may be reaching the end of it’s useful life and need replacement.  

Panel Size and Service Upgrades:

One of the most common reasons to consider panel replacement is to allow for additional space/breakers or to accommodate a service upgrade. Because the number of breakers required for a modern home or the amount of incoming power service has changed over the years, a panel upgrade may be required to allow for additional service or space to connect new breakers and circuits.

Federal Pacific or Zinsco Brands:

Both Federal Pacific Electric and Zinsco were major manufacturers of residential electrical panels commonly used from the 1950’s to the 1970’s (as late as the early 1990’s) and is it not uncommon to find them still in use.  Both of these panels had major manufacturing defects and have been involved in class action lawsuits over the years due to the risk of fire and even electrocution. Federal Pacific panels that used “Stab-Lok” breakers were not correctly UL certified and can fail to trip in the event of a surge. Zinsco panels had issues when circuits would melt to the bus bars and prevent breakers from tripping. Unfortunately with both of these panels, they can work just fine until they are exposed to a significant surge so they remain in use in homes even today.

You may be able to identify these panels by the embossed name on the outside cover or labeling inside the door but an electrician can easily confirm if your have either of these.

Code Changes:

As building codes and safety practices change over time, new code may require a panel upgrade or changes to comply with current building codes. This means a panel upgrade may be necessary even if you are doing “other work” such as a renovation. Most commonly this may be to accommodate an outside “shut off” or additional grounding.  

Maintenance or Replacement:

It’s a good idea to occasionally have an electrician check for any loose wires, tighten the lugs, clean any dirt or corrosion off and make sure the panel is weather tight if it is located outside, but panels do not require “maintenance” per se. For the most part, we recommend replacement if your panel has reached that age or you need to upgrade service, increase space etc.

How do I check my panel or know if it needs replacement:

If your home is more than 30 years old it’s a good idea to have it inspected to check condition and wear.  Most commonly, we replace an electrical panel in conjunction with other work being done such as a service upgrade or to increase size/available spaces in the panel.  If we are visiting your home for other work, it’s a good time to ask us to take a quick look at your electrical panel for any potential issues.

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Panel Maintenance

Ask the Electrician: Circuit Breakers

Q: My breaker tripped what does it mean?

Chances are we’ve all experienced a tripped breaker at some point. You plug in the vacuum cleaner, start the coffee pot and cut on the space heater and “click” no power! Most likely you have tripped a breaker.

Circuit breakers are a safety feature designed to protect against overload and short circuits.  They are basically a switch inside your panel box that senses when too much electrical current is being pulled or used by the circuit, the mechanism inside the breaker sense this and pulls the circuit apart, effectively turning the switch to “off” and stopping the flow of electricity.

Types of Breakers:

The most common breaker for residential use is a single pole 15amp or 20amp breaker. These are commonly lighting and outlets throughout the home. Most homes have multiple circuits like this (often grouped by room or general areas of the house) with each circuit having a breaker.

Items like EV Chargers, kitchen circuits, some large computer equipment etc., can require a higher amperage breaker. These are commonly 30amp -50amp rated and allow for more power to higher use circuits or for dedicated pieces of equipment/appliances.  They look almost identical to a 15a-20a breaker and take only a single “slot” in the panel. 

Large appliances requiring 240v power will have a dedicated two-pole breaker.  This means they have 2 “hot” wires and allow for the increase to 240v power. These breakers are larger, take more space in the panel and often have a larger “bridged” switch. These are most commonly water heaters, dryers and electric ranges.

In addition to these standard types of breakers there are now have options to include additional protection like GFCI or AFCI on a breaker level. There are even specialty breakers to provide combined protection AFCI/GFCI or surge protection for the entire home. For example if your bathroom outlets and lights are on a circuit that is GFCI protected on a breaker level then you do not require individual GFCI protection on the outlets themselves.

Resetting a Breaker:

If you know which things are run on the circuit turn them off. (i.e.: if the breaker tripped when you plugged in the vacuum cleaner, unplug it before resetting the breaker.)

  • Open your electrical panel

  • Take a good look at the breaker and panel itself for any visible issues like charring or melting

  • Look for any breakers in the “off” position (a clearly labeled panel is helpful to know which circuit may be the culprit) – note: a tripped breaker may also appear to be in a mid-position, look for the one that isn’t fully “on” or is out of line with the others.

  • Push the breaker fully to off position

  • Click it back to the on position (it should “click” back into the on position)

  • Close your panel

When to call an electrician:

Resetting a breaker is fairly simple but if you see any of the following, you should call an electrician for help. Generally if the breaker will not reset after 1-2 attempts, it may be time to call for assistance.

  • The breaker feels warm or is hot to touch

  • Any smells of burning or smoke

  • If the breaker or surrounding panel looks melted or charred

  • There are sparks or “sizzling” sounds

  • If the breaker immediately “trips” again

  • Breaker feels “mushy” and does not click into position

  • Breaker is seized and will not move (do not force the breaker or attempt to “hold it on”)

Replacing a Breaker:

Circuit breakers have a fairly long lifespan, up to 30-40 years under normal conditions but it is still good to evaluate them.  Most commonly a breaker needs to be replaced because it has been damaged while preventing a surge or short circuit. Always make sure that new breakers are compatible with your electrical panel and size of the wires in your circuit. Some of the most common breaker brands are Eaton, Square D, Siemens, and GE.

Fuses:

Some older homes have a fuse box instead of a breaker box for their main electrical panel, commonly if your home was built before the 1960’s and you have lower overall power service coming to your home.  Fuses protect against current overload similar to a breaker but cannot be reset, if a fuse blows it will need to be replaced.

What’s Next:

Most often a homeowner can reset the occasional tripped breaker but if a breaker is tripping repeatedly or showing any of the causes for concern, just give us a call. Our service trucks are stocked with the most common household breakers (and fuses) and we can check for any other issues and replace the breaker if needed.

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Circuit Breakers

Ask the Electrician: Can I DIY?

Q: What kinds of projects do you recommend for DIY?

Plenty of homeowners are taking on DIY projects for themselves to both save money and just for the enjoyment of completing tasks on their own.  For safety reasons it can be hard to determine what electrical projects are best to complete yourself and which ones require an electrician.  If you have any doubts it is best to contact a licensed electrician, better safe than sorry!

Be sure to give some thought to your experience level and knowledge before taking on any electrical DIY projects. Some homeowners are comfortable doing some basic small projects such as swapping out a light fixture, replacing an outlet or installing low voltage lighting and other will opt to call a professional every time.  Many of these small projects have great tutorials and other online resources that can be reviewed beforehand.

Safety First:

Anytime you are working with electricity, the safest thing to do is to turn the power off both at the wall switch as well as turning off the breaker inside your electrical panel. Always double check that the circuit is off before doing any work, never assume it is off. Check and double check to avoid the risk of shocking yourself or shorting out other wiring or appliances.

Invest in a few good tools for the project:

Some basic electrical tools are nice to have on hand even for smaller projects. We recommend starting with the following:

  • Circuit Tester

  • Lineman Pliers

  • Wire Strippers

  • Good Quality Wire Nuts

Look & Label:

If you are replacing a fixture or outlet be sure to look carefully at how the original is put together before removing any wires or taking things apart. Making labels or taking photos can save a lot of headaches when it is time to put things back together.

Some things are best left to an electrician:

Obviously there are plenty of projects that even a knowledgeable homeowner should call an electrician for. If you do not feel absolutely comfortable with your task it’s better to call a professional. We strongly advise against any DIY projects that involve the following:

  • Anything with the Main Electrical Panel

  • Any outlet or appliance that is sparking

  • Anything affecting the main service feed to your home

  • Wires or cables that are spliced, damaged or look burned

  • Any projects that require bonding or grounding to other systems                                                                                    

Not feeling comfortable:

It’s fine to change your mind and decide to ask for help. For obvious liability reasons we can’t “talk you through” a project or answer questions over the phone but are happy to schedule a service call or estimate and take over a project if you decide that DIY isn’t for you!

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Can I DIY?

Ask the Electrician: Holiday Q&A

Q: How do I keep electrical costs under control and safe during the holidays?

Tis the season and we are all hopefully making things merry & bright in our homes and with our families. These celebrations come with some extra costs and safety concerns that are easy to manage with a little thought.

Holiday Lights and Decorations:

Overall your holiday light display isn’t likely to break the budget for electrical costs but a little planning can make it a lot smoother and more energy efficient and avoid any faults/tripping breakers.

  • Timers: A timer is a great way to share your holiday light show when friends and neighbors are most likely to enjoy it.  It saves some electrical costs and puts “turning everything off late night” on auto-pilot.

  • Connections and cords: Take special care to keep any connections dry and out of the elements. These connection points are one of the most common causes of a tripped breaker or short in the system.

  •  Outdoor/Wet Ratings: Be sure any exterior lights are both UL listed and outdoor rated. Extension cords should be outdoor rated as well. Lights should be plugged into an exterior GFCI rated outlet.

  •  Trees and indoor displays should be turned off when you are not at home to enjoy them for both safety reasons and to save a bit of electricity.

Consider an upgrade: Most of us only use our holiday lights once a year (except that one “year round” neighbor that we all have), and in general we don’t replace holiday lights and decorations very often. Newer LED lights are both more energy efficient as well as generating less heat reducing the potential for faults. They also offer some cool new features!

Programmable Thermostats:

It’s chilly out and we all want to be comfortable. A programmable thermostat can help keep the house warm when everyone is home and save a bit of energy during the night (when we’re all cozy in bed) or when everyone is away at work. Check with your local energy provider for any tax credits or other credits for installing a programmable thermostat or signing up for off-hours usage for bigger tasks (laundry, dishwashers etc.) at a reduced rate.

Space Heaters:

A little chilly in the back office or upstairs bonus room? Space heaters can be a great way to keep a room extra cozy but should only be run while in the room.  They can consume a fair bit of energy if used for extended periods. Look for models that have an automatic shut off feature if they over heat or are tipped over.

Smoke Detectors:

It goes without saying that every home should have working smoke detectors but before the holidays is a great time to double check that yours are functional and have been tested.  Be sure to check the date on your smoke detector, they should be replaced every 10 years at a minimum. Unfortunately between kitchen accidents, Christmas trees and fireplace hazards, the holidays can be an increased risk for house fires, knowing that your smoke detectors are ready & working is great peace of mind.

Holiday Wishes & Office Hours:

The entire Dynamic Electric team would like to wish you a Happy Holiday and a wonderful New Year! We are sincerely thankful for our customers and the community that we live and work in for bringing us through what has been a couple of very challenging years. We look forward to many bright years ahead.

The office will be closed on December 23-24th as well as December 30th for the holidays.  


Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Holiday Q&A

Ask the Electrician: Preventing Shocks, Faults and Fires

Q: What is the difference between GFCI and AFCI?

Both of these safety devices are becoming more and more common in our homes. They protect against two major threats caused by electrical ground faults that can cause electric shocks (GFCI) and electrical fires (AFCI).

Most homeowners are familiar with GFCI or Ground Fault Circuit Interruption. As a safety feature, these have been required by building codes since the early 1970s.  GFCI outlets appear commonly in bathrooms, exterior outlets, crawl spaces and other areas that may be exposed to moisture.

Because water can be a conductor, proximity to moisture is a common way that electrical current can leak and result in a ground fault. Exposure to even small increases in current can cause severe or fatal shock hazards. The common visualization here is the hair dryer slipping into the sink or bathtub.  The GFCI senses even these small increases in current and reacts almost immediately (within a tenth of a second) to shut off current to the outlet.

GFCI are easily reset at the outlet with a small reset button. If your GFCI does not reset or continues to trip, you should contact an electrician to determine the problem. Additionally, GFCI switches should be tested periodically to make sure that they are working. As our homes age, existing GFCI outlets may have reached the end of their useful life and need to be replaced.

AFCI or Arc Fault Circuit Interruption provides protection against electrical fires by detecting irregularities in current caused my arc faults.  AFCIs can be installed at a breaker box level or in receptacles that look similar to the more common GFCI outlet.  Both the breakers and the outlets have a reset switch that must be reset if tripped.  AFCI protection started to become a requirement in 2002, primarily for bedrooms and today is a building requirement for most living areas in the home.

Arc faults are most associated with electrical fires because the “arc” can result in sparking and excessive heat that can easily ignite any nearby materials.  Old, frayed appliance cords, loose connections or pinched/punctured wiring can all cause arc faults. The common homeowner accident is nailing into wires in the wall while hanging a picture. Because most electrical wiring is hidden from sight, electrical fires can spread behind walls and present very dangerous conditions not immediately detectable by smoke detectors.

The sensing technology for AFCIs has improved a great deal but older technology was responsible for many complaints of “false tripping” so AFCIs are not as widely accepted or known as GFCI protection. Today homeowners that are updating existing homes, especially older retrofits may need to look at several options for AFCI or a combination of the breaker and outlet styles. This is because appliances, wiring types and AFCI technology have all changed over the years, so retrofitting can require some research and a bit of fine tuning for how all of the components will work together.  Don’t be discouraged if it takes some investigation.

Electrical safety has come a long way and continues to improve. Let us know if you have any questions about either the GFCI or AFCI protection in your home.

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Preventing Shocks, Faults and Fires