Step 4 · Install New Fan-Rated Electrical Box and Brace
If the existing box is not fan-rated or is not securely attached to a joist, you must install a new one. For new installations or replacements, use a fan-rated metal or plastic box. The box must be capable of supporting at least 35 pounds (and preferably 70 pounds for safety). If the box is not directly attached to a joist, install an adjustable fan brace between two joists. Follow the manufacturer's instructions for the specific brace and box to ensure they are securely mounted to the ceiling joists, providing a sturdy anchor point for the fan.