Here's another view in the entry hall, now looking towards the kitchen, with the dining room entrance on the left. (theinspiredroom.net)
Using the balcony above the underwater hidden room entrance as a reference, this chest is left of it on a spiral staircase on the ground floor outer ring. (dulfy.net)
We already have a mud / laundry room entrance on the side of our house. (beneathmyheart.net)