I am going to rewire an apartment since we are opening up the floors to level them. This apartment is very old and at the time, someone decided to run all the NMD cable along the baseboards on the outside. I want to move everything to underneath the floor and through drilled holes in the floor joists.
To do that I have a few questions; I have attached pictures of the current mess where the cables all go into the panel.
(a) All the wire is NMD but of varying age, can I re-use this wire or should I repull new NMD cable manufactured during the current year? I don't think there is any difference in copper spec, it's just the sheathing that on 1 or 2 wires is looking brittle (orange and grey/black coated sheath) (not knob tube)
(b) Is there a recommendation of number of amps per room (non kitchen, non bathroom), say bedrooms, lounge, etc.? You can have up to 12 receptacles on a circuit but this might be limiting.
Could I put one 15A circuit per room for receptacles then do the entire apartment lighting on one dedicated lighting circuit (6 rooms)?
(c) I'm thinking of tidying up this mess by taking the wires through the floor of the kitchen, ceiling of 2nd floor and then to each of the rooms after that. Is it worth putting a big junction box / sub panel in to manage that or not?

 

You could reuse cable that is undamaged as long as it is NMD90 (rated for 90C temperature) and is in otherwise good condition such as no kinks or cuts. Cable earlier than about 1990 does not have the 90C temp rating and cannot be reused.

To tidy up the cable entrance I would run a pair of 1-1/4" conduits from the bottom of the panel down into the pull space under the floor. You could use those pipes to bring all the cables up into the panel.

I don't know the specifics of Candaian code on circuit sizes, but the rule we use here is at least 3 watts per square foot (32W / sq meter) for general living areas like bedrooms and living rooms. A 15A circuit supplies 1800W and a 20A circuit supplies 2400W. Kitchens require at least two 20A circuits; and bathrooms require at least one 20A circuit. You are free to add more than this if you think the situation or rooms demands it. For example if the bedrooms will use window air conditioning units or space heaters, run extra circuits to those areas.

I'm sure the specifics of these rules are different for Canada, but they are probably close for your planning purposes.

 

Thanks!
how many NM cables per 1.25" conduit?
and is there a way to get the conduit flush to the panel?

 

how many NM cables per 1.25" conduit?
and is there a way to get the conduit flush to the panel?

 

I only seem to have one big knockout at the bottom of the panel. If I put the wires in there to the floor day a 4' section of pipe, is there any need to derate as there will be a few wires with sheath in the same conduit.

 

For what it's worth, I would probably rip it all out and start over. Take all that old wire and recycle it and get a few $$ back. By the time you try to recover the old wire, you'll be spending way more time than just pulling fresh new cables.

Definitely spend some time reading about current codes regarding dedicated circuits (kitchen/bath/laundry) and receptacle spacing in rooms. I know there are some CEC "oddities" (from a US perspective) like having the top/bottom of the kitchen duplex receptacles on their own circuits along with where 20A circuits are required.