Knob and tube wiring is very common in older buildings. If you find knob and tube wiring in an apartment building it can have serious consequences. For one, it can be a fire hazard and you may not be able to get insurance for this property until the situation is rectified.
Rectifying the situation can be extremely costly as it entails opening up walls.
In this vlog post, I discuss knob and tube wiring with the amazing building inspector, Allan Spisak of ACISSS Home and Commercial Inspection Consultants (www. aciss.ca). I guarantee you you will not find a better and knowledgeable inspector in Canada.
If you want to explore this topic further, below are some links on knob and tube wiring!