A lot of homes in Roanoke, Salem, and Vinton still run on 100-amp panels installed decades ago, when a house had one TV and no central air. They're not unsafe by default, but they run out of room and capacity, and some brands from that era have a documented failure history worth knowing about.
Sign one: breakers that trip when two things run at once. The microwave and the toaster, the dryer and the hair dryer. That's a circuit at its limit, and often a panel with no room to add another.
Sign two: no open slots, or tandem breakers stacked into every space. If you're planning a kitchen remodel, a basement, a hot tub, or a workshop, there's nowhere to put the new circuits.
Sign three: an EV in the driveway, or one on order. A Level 2 charger wants a dedicated 40- to 60-amp circuit. On a full 100-amp panel that's usually the tipping point for a 200-amp service upgrade.
Signs four and five: flickering lights when the HVAC kicks on, and any warmth, buzzing, or scorch marks at the panel itself. The last one is a call-today situation, not a next-month one.
An upgrade means a new 200-amp panel, a new meter base if the utility requires it, a permit and inspection, and a few hours with the power off. It's a one-day job for our crew, and it makes every other project you're planning simpler, including that generator connection you've been thinking about since the last ice storm.