Moving Attic Access -- Same Rafter or Different ??

wrldruler

I am converting my garage into a family room. I have an existing access panel for the garage attic. Problem is that it is located right next to where I want to install a ceiling fan. The fan blades will block the access panel, so I want to move the opening just enough to avoid the fan.

The current opening was made by cutting one 2x10 rafter, and heading it off.

I have 2 choices. I can move my opening like 12 inches North, or like 32 inches West. I need your advice on what is more structurally sound.

For the North option, I would stay in the same rafter bays. I would cut the same rafter another 12 inches or so, and put another header board across.

For the West option, I would jump to a different set of bays. I would cut a new rafter, and add header boards across.

Structurally speaking, which is my better option? Cut the same rafter another 12 inches, or cut a new rafter?

Thanks,
Chris

Tinstaafl

Just to pick a nit, those aren't rafters, they're ceiling joists. Rafters run uphill on the underside of the roof.

By having one joist cut apart in the center, you've weakened the overall ceiling structure by X amount. The weight which originally was carried by the cut joist is now being transferred by those "headers" to the joists on each side. Now, if you cut one of those joists, you're essentially doubling the load being transferred via headers.

Unless you have a gazillion pounds of stuff stored up there, either approach would be fine. But ultimately, the better structural approach would be to shift the opening along the length of the already-cut joist.