Francomb, 20, spent last season on-loan at Hibs.
"I'm over the moon," he told Canaries Player. "I've had half a season up at Hibs and now I'm back.
"I can't wait to get on with pre-season.
"It was brilliant for me to play up at Hibs - it was a completely different environment, but the season before I did it with Barnet, so it wasn't too different to that, just on a bigger scale."