Hey there,
I'm trying to make our home more energy efficient. There is an attic hatch roughly 23 x 29 that is not used as we have a second one. I'm trying to figure out the best way to do this. Should I cut back the existing drywall to expose half of the rough ins and screw in my new drywall into this? Or should I screw in new rough ins around the existing ones on all four sides and screw in the dry wall to these?

Thanks,
Derek

I'd leave it as is, and make an insulation blanket to put above it, using a large trash bag and some fiberglass. That's what I did for my folding attic staircase, except I used a cheap tarp for a much bigger blanket.
You never know when you might find that hatch handier than the other one.

Just sister 2x4 to the existing ones and add one in the middle. Then drywall over the hole and finish. Make sure to insulate the fill on piece.

Joypulz,s way is the easiest and will give you excess if you want it in the future.

Chuck