The 21-year-old Jamaican forward has only made six first-team appearances for the Canaries since he stepped up from the youth squad in 2013, scoring once back in March 2014.
Loza has previously been on loan at Coventry, Leyton Orient, Yeovil and Stevenage, plus two loan spells with the Shrimpers.
"We know he's got pace and a eye for goal," said manager Phil Brown.