our rough calculation these days is that for a small sized family (family of 4), you'll need at least 200Amp panel, where 300Amp is ideal.
Assuming that the rental unit is part of the house and does not require separate panel (i.e. laneway house).
You'll also need a new breaker panel(with at least 30+ breaker slots in it), coordination with a certified electrician to do the job.
Lastly: also consider portion of them breakers to be of AFIC type (not the standard GFIC type), to prevent possible slow-current leak related fires from happening from behind the wall (studs) or other slow shorts.
Thank you Quest. electrician said can upgrade from 60 amp to 100 amp and there is no need to get a permit from the City. However, two Reno guys said electricity upgrade needs to get a permit from the City. Which side is correct?
Always get a permit from the city (and then document/keep them in a safe place afterwards).
Insurance company will refuse to compensate you if the work performed by electricians (upgrading electrical panel, in particular) does not come with a relevant permit.
Also: if your so-called electrican trying to talk you out of getting a permit (even just a small uprade from 60 Amps to 100Amps), don't use him. Go find another one whose more than willing to work with you to get the necessary permit before performing the upgrades.
Thx Quest. Then should I at least ask the Reno guy to start doing Touch ups (patching holds in walls) in the house? Or even finish reno inside the house first and then upgrade the electricity very last?
(1) you said the house if 50+yrs old, are the wall (AC) outlets still on 2 prongs or 3 prongs (3 prongs meaning that there's a center pin for ground)? If 2 prongs, you'll definitely need to upgrade them all in order to get proper house insurance for that (for your proper protection).
The best time to deal with this is during reno where you can punch holes on the walls, pull new electrical cables, etc.
if you patch the holes, paint the interior walls, etc. before re-running any new electrical wiring pulls that's gonna cost you major: poking holes on walls again, etc.
(*I did some work on 50+ yrs old houses on Oak Street before, and for that I knew the insurance part*)
2 prongs and no ground, that does not meet electrical standards nowadays (thus the refusal for all the insurance companies in Canada RE: insuring your (or your friend's) house.
nowadays, it must be standard 3-prong (with ground) NEMA 5-15 for wall jack AC outlets.
So, for that house: a new house breaker panel + re-run all the electrical wirings throughout the house in order to meet the standard requirements.
You (your friend) skimp on this, then anything goes wrong, insurance will not compensate once discovered that the electrical wirings are not up to standard.
While the house is still in reno stage: it's best to pull all the walls out (beware of asbestos, esp. 50+yrs old house, and or/lead based paint which was very common back then), re-run all the electrical wirings, check for hidden (or illegal ) junction boxes of any sort...
Unfortunately, this is not gonna be cheap. Good news is that once this is done properly, you (your friend) will not have to worry about overheating, hidden junction box failure (may lead to house fires), etc. and most important of all: he can get insurance (make sure the job has proper permit on it).
Thx Quest. By the way, how much will it roughly cost to get all the things done? Pull walls out? You get rid of all th existing drywall? Rerun all new wiring and then new drywall?