pepsi_man on Nostr: 2 x 4 is just the nominal size. The actual working size is the finished product after ...

2 x 4 is just the nominal size. The actual working size is the finished product after it's been planed down. You can find Amish lumber mills that only use 2 x 4 "rough cuts" that are actually 2 inches by 4 inches.

Why?

No clue, and to me rough cut is fine for house framing.