Studying the plans on Google I'm tried to make it all a bit clearer
The EXTENSION is shown in the area surrounded by red
It is linked to the main house by a corridor. This corridor also houses the diary room entrance
The new extension is a double floor height with a balcony and a big garden
The new eviction set has a canopy over the top with lighting rigs. It has a walkway to the studio for interviews.
There are TWO sets of stairs into the house. One to the main house and one to the extension