Other than the safe house....
 

...are there any other secret rooms? And if so, when will these be revealed?

I was led to believe (on launch night) that there were rooms upstairs :conf2: bit late now to reveal that though.

By Emma? Yeah - same, but this ended up becoming the Diary Room. :bored:

They can't put much rooms upstairs though anyway, they never will unless the house itself moves. Due to it being built on a water tank, there's not much support for them to literally build a complete second floor.