Hi,
You are granted points based on each of the 4 language skills in IELTS not the overall.
Let me give you an example. The overall of all the following results are 7.0 but the points awarded are different.
R. 6.0--> 2 pts
W. 7.5--> 4 pts
S. 7.5--> 4 pts
L. 7.0--> 2 pts
TOTAL: 12
R. 7.0--> 4 pts
W. 7.0--> 4 pts
S. 7.0--> 4 pts
L. 7.0--> 2 pts
TOTAL: 14
R. 7.5--> 4 pts
W. 6.5--> 4 pts
S. 6.5--> 4 pts
L. 7.5--> 4 pts
TOTAL: 16
R. 6.5--> 4 pts
W. 7.0--> 4 pts
S. 7.0--> 4 pts
L. 8.0--> 4 pts
TOTAL: 16
So it all depends on your scores per each band.
To calculate your points please check:
http://www.cic.gc.ca/english/information/applications/guides/EG72.asp
Good luck,