The athletic second row, who is Irish-qualified, was a valued member of the Harlequins Academy, and he made five appearances for the distinguished Aviva Premiership side before he decided his long-term future was with Ulster. Treads has since become a dependable member of the Ulster senior side and has went on to represent Ireland. Treadwell was a part of Andy Farrell's side in the 2023 Guinness Six Nations squad and part of the Rugby World Cup training camp.