DO I NEED A SERVICE UPGRADE?
How do you know if you require an electrical service upgrade you ask? You will need to contact a electrical company to do a Load calculation for you, or if you are in this situation you will need to upgrade: Say you want to build a workshop or a garage and take 100 amps to it, your regular 100 amp main panel will not be able to handle this new load and will need to be upgraded to a 200 amp service (maybe more depending on your needs).
Doing a load calculation will figure out what the required minimum amount of amps is required to run your home/shop or both without any issues eg. tripping the main breaker(major issue), and from there it can be determined with the Canadian Electrical Code rules in mind, the size of Service you need. You may have had the same electrical panel in your home for 50+ years and have never needed to add anything to it, and if you never add anything you will not need to upgrade your service.
Reasons to upgrade may include adding a sauna,or a hot tub. These two items require a lot of power to heat them up. The hot tub especially as heat loss is dramatically increased by the cooler weather.