The 27-year-old Scot, who finished last season on loan at Bloomfield Road, has signed a two-year contract with the option of a further year.
"It's good to have it all tied up now and be able to focus on the new season," he told the club's official website.
"The three months that I had here were pretty good. It gave me a taste of Championship football and made my mind up of where I wanted to try and play.
"I've been given the opportunity to come here and do that so hopefully I can do well."
- Sports & Recreation