A:Answer The official depth is 30.38". The largest item behind the machine is the dryer vent, unless you vent it to the side. If venting from the rear there should be plenty of room for the rest--hoses and electric, unless your situation is unusual. There are also flat dryer vents that can save room, if you need it. (See the product I added to this post.)
Note that in the front, the cabinet of the machine is about 29" deep, the doors protrude about 1.25". In my case, a wall is 30" deep, the cabinet of the machine ended up a bit beyond the 30" wall & the doors protrude a bit more, but to my eye, it looks fine. It's a walkway in front of my machine, so I am concerned about depth, but it's fine. In the photo, the cabinet looks about even with the shoe moulding.