Due to the removal of a wall, I have a couple of circuits that aren't long enough to go anywhere except into junction boxes located in the 18 inch joist space below the subfloor. Immediately below this space is double 5/8 drywall (the garage ceiling). My plan is to put an access panel made out of drywall (for fire protection) in the garage ceiling so that the junction boxes are "accessible". Will this be acceptable? The plumbing inspector has allowed me do the same sort of thing to access a gas line union. Electrical inspector hasn't come yet. How large of an opening is required? The plumbing required a 12x12 opening. If I had to I might be able to get the boxes to be located over the basment ceiling instead of the garage, but I'm not sure one of the lines is long enough for that either.