Do you have to be in the same house to use home sharing

You have to be connected to the same network.

http://support.apple.com/kb/ht3819

No you don't, as long as you are connected to the same wifi network.

Stonsey wrote:

Can you home share with those not living at home?

You need to be on the same WiFi network which means that you must be in the same house (or pretty darn close) in order for it to work.