Question on database refresh.

I have a doubt regarding DB refresh, Please advise if my understanding is correct, when we refresh a database the Log file grows the size of database size? 

Example:

Suppose the database size is 10 GB, during the refresh operation we need 20GB of free space in drive as 10GB for data file and log file respectively, once the refresh is complete then we will have 10GB for datafile and few Mb for log file, so there will be 10Gfree space in drive... 

Please explain it for Sql 2000, 2005 and 2008R2

Thanks.