What is the difference between VURB and JV3?

VURB and JV3 are both verification methods of compliance with the energy efficiency requirements of NCC. The methods and are basically the same methods but applicable to different building classes . VURB is an alternative solution to achieve compliance under NCC Vol 2.0 Part 3.12 for Class 1 and Class 10 buildings. JV3 is an alternative solution to achieve compliance under NCC Vol 1.0 Section J for common parts of Class 2, Class 3 to Class 9 buildings.