The wrong-sized wire can lead to several safety hazards, including structural fires, surges, power outages from tripped breakers, and electrocution. It’s important to follow the American Wire Gauge system and the National Electrical Code guidelines to safely wire a home. Electrical wiring is not safe for homeowners to handle and is best left to a licensed electrician.

If you have a lamp that flickers or doesn’t stay on, it’s a sign that it’s time to rewire it. Additionally, it’s important to rewire antique lamps so they’re safe to continue using without the risk of an electrical fire. If the plug on your lamp is more than 15 years old or you notice poor performance like flickering, you should hire a lamp repair service to rewire it. If you’re upgrading the bulbs in an antique lamp from incandescent to LED or CFL bulbs, rewire it so it’s compatible with the modern bulbs.

It can be safe to buy or live in a house with knob and tube (K&T) wiring, but only if the system is in good condition, functional, and has been thoroughly inspected and approved by a licensed electrician. Never purchase a home with K&T wiring without getting a professional electrical inspection first.

Key considerations include:

• Safety and Condition: An inspector will verify that the wiring is safe and has not deteriorated. Over time, the insulation can wear away, leaving exposed wires that pose a significant fire or shock hazard.

• System Capacity: The electrical service should be at least 60 amps. However, even at this capacity, K&T systems often struggle to handle the demands of modern appliances and electronics.

• Lack of Grounding: Knob and tube wiring is an ungrounded system, which is a safety concern for many modern devices.

• Ongoing Maintenance: If you live in a home with K&T wiring, it's recommended to have it inspected by an electrician every one to two years to ensure it remains in safe working order.

Ultimately, any inspection or modification of a knob and tube system should always be performed by a certified professional.

How far you can run underground electric depends on the wire gauge (generally AWG) and the circuit voltage. Too much voltage drop in an electrical circuit can negatively affect performance, so the smaller the voltage drop, the better. Ideally, it shouldn't exceed 3%. The smaller the wire and the longer the run, the more significant the voltage drop. 

For example, with a 120-volt circuit, you can run 60 feet of 12 AWG cable without losing more than 3% voltage. With a 240-volt circuit, you can run 120 feet of 12 AWG wire while maintaining a voltage drop of 3% or less.