I am currently reading the "Canadian Electrical Code, Part 1" in preparation for this DIY electrical work, but it creates a lot of questions that I am hoping someone with experience can help me with.
Most of my ceilings in the basement is drop-ceiling, covering exposed joists above. All the existing wiring is stapled to the bottom face of the joists, which according to CEC is not allowed anymore, so I cannot do it that way, correct? I am basing this on Rule 12-514-b:
Cables shall not be run on or across the lower faces of basement joists, unless suitably protected from mechanical damage.
So I guess that means that my only option is to drill holes through all the joist and run the cables that way. This creates 2 questions:
Q1) What do I do when joists have HVAC ducts taking up the space between the joists that I need to cross? I know that cables require a minimum separation of 25mm from heating ducts, so what are my options? What kind of "mechanical protection" do I need to use, if I do need to staple to the bottom of the joist?
Q2) I have one 3-wire circuit and two 2-wire circuits to run. Can they all be run in the same hole? I can't find any info in the code about how many NMD90 wires are allowed in one joist hole...
Next, there's the question of how to run the wire over the part of the ceiling that is not accessible to me. There's a dry-walled, dropped section of the ceiling running along the entire length of the basement, and that I need to cross before I can get from the panel to the side of the house where the drop-ceiling is. What are my options for crossing that space, considering that I cannot support the cable every 1.5m as per Rule 12-510-1-a, without completely opening up the ceiling?
I found this rule about fishing wire:
== 12-520 Fished cable installation == Where the cable is used in concealed wiring and it is impracticable to provide the supports required by Rule 12-510, and where metal sheeting or cladding, metal joists, metal top or bottom plates, or metal studs are not used, the cable shall be permitted to be fished.
So my last question is:
Q3) Did I understand correctly that I can simply fish the wire over the obstruction w/o any sort of conduit? What if that space contains metal HVAC ducts? Do I need to use some sort of conduit then? Is NMD90 wire even allowed to be run through conduits? What are my options?
Any advice would be greatly appreciated!