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.

Single-pole light switches are the most common light switches on the market. Their simple features make them easy to install and use. For more powerful applications that require 30 or 40 amps, you may need to use a double-pole switch. Some homeowners may want multi-way switches like three-way or four-way switches to control a light fixture from opposing ends of the room.

Typically, a local home energy auditor is responsible for performing energy audits. A home energy auditor will conduct one of three energy audits designed by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) to determine the energy efficiency of your home. The auditor often provides analysis that can help guide changes and improvements to your home for better energy efficiency, giving recommendations as necessary.

If half of a string of Christmas lights is out, it is likely because of a single burned-out, loose, or broken bulb within that section. Long strands of lights often contain more than one circuit, so when one bulb fails, it can cause the entire circuit (or half the strand) to go dark. To fix this, inspect the unlit section and test each bulb to ensure it is tight and functioning properly. Replacing the faulty bulb or repairing a damaged shunt will typically solve the problem.