What exactly is knob and tube wiring?

In Toronto, this question comes up often since most neighbourhoods close to the downtown core date all way back to early 1900’s, with homes well over 100 years old. If your home was built in 1950 or earlier, chances are it was built with knob and tube wiring. Sometimes knob and tube wiring is easy to spot when the full or part of the basement ceiling is unfinished. You will be able to see wires running through porcelain cylinders, known as “tubes” inserted in holes in the wooded floor joists.  “Knobs” will also be present, which keep the wires secure and away from the wood along which the wires run. The actual wires should be insulated with a rubberized cloth fabric. If the wiring in the home has been updated, those tubes and knobs might still be visible in the floor joists, but the wires have been cut off, making them inactive.

When faced with a decision whether to buy an older house with knob and tube, don’t panic. Understanding knob and tube wiring and how and when it can be replaced will give you a lot of perspective. Here are the most important facts to know:

1) It’s not always dangerous

This type of wiring has been used for decades, is still predominant in many older Toronto homes and is not actually dangerous without a cause. Problems arise when the insulation around the wires begins to deteriorate with age, or when sloppy alterations have been made to the wiring. A great way to get peace of mind is to hire an electrician who can do a throughout inspection to ensure the existing k&t is in fact safe and does not require replacement right away.

2) You can get home insurance

Just like the previous owners living with knob and tube, you will be able to get home insurance. There are insurance providers that offer appropriate coverage (albeit at a higher rate). You might be required to provide an electrical report of safety if the home is full of k&t, but this will also offer you peace of mind.  Insurance coverage should not be a deal breaker.

3) Budget to replace it when the time is right

The Ontario building code does not actually require knob and tube wiring to be removed, however new construction or major renovations will require modern wiring to be used. If you are buying an older home that is full of k&t or has parts remaining, you should definitely consider the cost of replacing it. Ideally this will be done with a future renovation to save costs on wall and ceiling patching. On average a typical 2 storey 1400 sqft detached home in the west end with cost approximately $18,000 – $20,000 (more if renovation prices keep rising) to rewire completely. In order to replace the wiring, an electrician will need to make incisions in the drywall or plaster. It’s optimal to remove old wiring during a renovation as these holes will need to be patched and painted. If you are planning to renovate in 2-3 years, it’s probably best to get a k&t inspection, ensure it’s safe and leave it until the renovation.

★ For more need to know real estate info check out:

• Open Permits: What Every Seller Should Know
• How To Win A Bidding War In Toronto
• How To Evaluate A Good Fixer-Upper

4) Don’t be fooled by knob & tube free home inspections

To rewire an entire home is a pretty big undertaking and unless a house has gone through a complete gut job, and all the old wiring has been fully removed from the walls, there’s a high chance there may be some remaining k&t in the walls or ceilings (somewhere!). This is important to remember when evaluating homes and if this thought completely freaks you out, then you should only be shopping for newly renovated homes or new builds. We come across this often when we read home inspections or speak to agents who say there is no k&t in the house, but the seller has no proof that it was all removed. Buying an older home comes with some uncertainty because unless you open up those walls, you will not know what you will find. This however should not be a deterrent in the slightest if you love character homes. Wiring can all be fixed, it’s about understanding what steps to take to fix it and when.

5) Change your mindset

Because there is never a guarantee that a home is completely free of knob and tube wiring (unless extensive renovations have been done), it’s important to be objective and not miss a great home buying opportunity. Change your mindset and consider k&t as an old house feature that may or may not present itself and budget for it accordingly. If replacing k&t is not in your budget and old wiring scares you, then you should probably give these homes a miss. However, if you are planning to do future renovations, and love old character homes, then remember that old wiring is just one potential problem you may discover, there could be more, and that’s ok.

★ Check out these additional resources that are a must-read anyone buying a house in Toronto:

• Why You Should Take Advantage Of Your Buyer Visits
• Climbing The Toronto Property Ladder 101
• The Real Estate Debate: Should I Sell Or Buy First?

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