Flat extension cords vs round extension cords: Flat cords win for under-rug use, but neither is truly safe

Flat cords are better because they lay flush and avoid the trip hazard round cords create. But running any cord under a rug risks overheating and fire, especially with thick rugs or heavy furniture. If you must, use a flat cord with proper gauge and no heavy cover—or route along the baseboard with a floor cord cover instead.