Knob and Tube Wiring:

We are London’s knob and tube specialists. There are a lot of conflicting messages and information about knob and tube wiring. We hope this page will assist you in learning about this older wiring system, the safety of your home and family and what solutions we offer to upgrade your electrical system.

If you have further questions not found on this page, please contact us at xxx@finanelectric.com for a free home consultation.


Knob and Tube – At a Glance:

And across other porcelain insulators called tubes…

 

For some people, knob and tube can be frightening:

 

Is knob and tube safe?

There are three main problems with knob and tube wiring:

Oh really, it can’t be that bad…

Well, you never know what you’re going to find behind the walls. Believe it or not, that’s how we found it behind the plaster – a fire waiting to happen. Because we have rewired literally hundreds of houses in our area, when someone asks us, “Is it safe?” we have to respond with an educated and qualified, “No.”

Unfortunately, because over 90% of the wiring is concealed behind the walls, how could anyone really know if the old knob and tube is safe?

We consider knob and tube wiring like any other aspect of home maintenance – like your roof, your furnace, the plumbing, etc. There comes a time when old, outdated equipment needs to be replaced.

We prefer preventative maintenance and repair of your electrical system, as opposed to responding to emergency calls when disaster strikes.

Quite often, someone, somewhere and some time made some changes to the old knob and tube wiring. When knob and tube is manipulated, modified, or in this case, spliced into with new wire, you’re just asking for trouble. Handyman modifications to knob and tube are one of the biggest safety hazards.

When the wiring is exposed to the elements, it has a tendency to dry-out and become very brittle. This causes two problems. First, the insulation can crack, exposing the copper wire beneath and second, the connections like the ones above will become very loose.

Think your knob and tube is in good shape? Go downstairs and look for areas where the wiring has been “patched up” with electrical tape over the years. Unfortunately, tension on the wire, combined its manipulation can cause it to break or snap. Rarely do we find a house in our area where this has not been a necessary repair in the past.

Another very serious fire hazard that causes the deterioration of knob and tube wiring and unfortunately occurs quite commonly is the dreaded shared neutral. In this situation, one neutral wire becomes overloaded when the hot wire from another circuit gets tied into it. See the diagram below:

As you can see, circuit #1 now has two “Hot” lines (indicated by the red “H”) connected into it. This creates increased resistance in that neutral wire as it is “shared” by those two Hot wires. Increased resistance leads to heat build-up. This heat build-up commonly causes those neutral wires to become very dry and brittle. In more drastic circumstances, resistance at connection points, as in old switches and two-prong receptacles, can cause these devices to char, melt and potentially catch fire.

Wow, what can we do about this?

Here is where you are going to find differing opinions. Clearly there are some reasons why knob and tube wiring should be replaced, but not everyone has the time, inclination or budget to rewire their house.

Band-Aid Fix: Knob and Tube Clean-Up

In the past, “band-aid” fixes have been appropriate to home owners as an alternative to a house rewire. In response to insurance requirements and real estate transactions, many people in the past five years have chosen to do a, “knob and tube clean-up.” As a company, we chose a long time ago not to perform band-aid fixes. We are determined to look after the long term interests of our clients and provide the best value for their money possible.

A knob and tube clean up is where the basement and attic wiring are cleaned-up and GFCI receptacles are used to provide some degree of protection to the circuit. The thinking here is that by cleaning up the basement wiring, you’re likely to correct many handyman modifications and areas where the wiring has been broken as a result of manipulation.

Unfortunately, as we saw in the above picture, we commonly find real safety problems concealed behind the walls and not located in the basement or attic. As well, GFCI receptacles will not work in situations with shared neutrals. As a result, homeowner’s can spend upwards of $2500 performing these band-aid fixes, only to find that they’ve wasted their money!

There’s another important reason why we have chosen not to perform this repair. Simply put, it is seen as devious in many situations, as the knob and tube effectively becomes “hidden” in the sense that all one sees in the basement is new wiring. Without sufficient background and knowledge, quite commonly we have found new homeowners shocked that the house they thought was completely rewired was, in fact, not. We have seen far too many lawsuits over this issue in the past few years and as a result, have chosen to take the high road by only offering a solution that suits everyone’s best, long-term interests.

Insurance companies and knob and tube wiring:

Not only that, but these days, most insurance companies will not insure people with know and tube wiring, and cleaning up the wiring in the basement does not replace any of the wiring to the receptacles, switches and lights in the home. Therefore, many people have found that, although they’ve spent some money to “correct” their knob and tube woes, their solution does not satisfy their insurance company’s requirements.

Thinking of selling your home?

In today’s real estate market, finding a buyer who’ll purchase your home “as-is” can be a daunting task. With things tightening up, buyers are expecting more for their money, and given that many, many people have spent time, money and energy upgrading their homes, there are typically better options and value for their money on the market than a house that still needs the knob and tube replaced.

The Only Real Solution: Rewire the House

The best solution is to rewire the remaining knob and tube and bring the home up to today’s codes and standards. This involves a major construction project that can take up to three weeks to complete.

Can I do it myself?

Absolutely.

No seriously, leave it up to the pros, who can bring things up to current code and make your home safe for you and your family…

Most two-story houses take approximately one week to rewire – don’t take a one-week project and turn it into months of agony.

What about holes in the walls and ceilings?

This is true. In order to rewire a home, in many cases we are required to make access points when we encounter studs and joists. The holes required for a typical light fixture on a main floor would look like the picture below:

We work very hard to minimize the damage to walls and ceilings. In fact, we recently rewired an entire two story house in old-south with only three holes! Our electricians are Wiring Wizards and are the absolute pros in working in London’s older homes. We receive a lot of requests to rewire London’s finest homes, when the utmost care and sensitivity to the heritage of the home are required.

So how much does this cost, anyway?

We prefer to think of a project like this, as with any major renovation project, as an investment that adds value to your home. A typical home rewire will range anywhere from $5,000 - $10,000, depending on the size and extent of rewiring that’s already been performed.

What’s this “free consultation”?

Unlike everyone else in the city, we are prepared to spend hours with you, at no charge, to evaluate the knob and tube wiring in your home and provide recommendations on repair and replacement.

If you’d like to learn more about your system and investigate the possibility of rewiring your knob and tube, contact us for a free, no-obligation home consultation.

Thank you for reading and we hope this page has provided valuable information to you.