I tore off My roof on a Ranch and made it a two story raised ranch. I canalevered it off two feet in front and two feet in back. On the first floor soffit it now has an overhang of two feet.
When We built it I remember the carpendar telling Me not to stuff in much insulation and He put up vented ALuminum soffits. It didn't sound right at the time. Hence I get airflow from outside pulled in between the ceiling and the upper floors. That's a 23 inch opening between floors as We built the floor deck above mechanicals. It should have been sealed and not treated like a second floor Soffit that needs airlow up to the attic. My furnace runs constantly on first floor as I sucking in air between floors and outside soffit. I hope this makes sense. It My belief that this should have been totally sealed and insulated mis level between the first and second floors. I took a light fixture off in the kithchen ceiling and could feel ir pouring in as well as tile floors upstairs are freezing even in 5 feet.
Anybody ever seen this problem and fix?
Chiacgo area
DrDreamie

I would take down the perforated soffit and insulate the overhang and use non perforated soffit or plywood. There is no need to have air going through the floor joists of the second floor.

Yeah, or you can insulate it, and if you didn't jack up the aluminum, put some tar paper up and then the soffit. If you got the dough, just get some wood soffit material