Writeable folders and files

[spd2612]

I am in the process of moving my Template from IIS to Ubunto Apache2
I have got it moved using a sub domain
Permissions are my big concern I set the root folder to me and group to www-data this way I have full control and the site and php use www-data
I need to know what permissions does www-data need and what folders will need write permissions I know the cache folder in the root and users.txt
Is there anything else?