Performing the framing for a ceiling fan on I-joists is best the ceiling open.
Ceiling fans do not require specialized framing for hanging, simply a solid support that stays that way when subjected to years of vibration. The most common method for framing an I-joist for a fan is to create another "I" shaped support above the ceiling. This framing houses the junction box in the center, and serves as the central anchor point for the entire assembly. It's best to do the framing while the ceiling is open and free from obstructions.
Instructions
1. Locate the desired spot for the ceiling fan. Insert two 16-inch 2-by-4 planks in between the I-joists, tapping them into place with the rubber mallet. Mount these vertically and tight against one another, so the short sides (the 2-inch sides of the 2-by-4s) are facing down. The junction box will be mounted to these pieces.
2. Screw in at least four wood screws per plank from the side of the I-joist into the ends of the wood pieces. This is done with the drill and Philips-bit attachment.
3. Screw in the junction box with four additional wood screws, centered on the 2-by-4 planks. Route any 110-volt wiring through the side of the junction box, and cap it until you're ready to hook up your fan.
Tags: 2-by-4 planks, ceiling open, , wood screws