Hi, I would like to add an exhaust fan in my small half bathroom on the first floor (it’s a 2 floor semi-attached home). The bathroom becomes very humid and takes a few minutes to eliminate odors. I’m planning to hire an electrician to install the fan with a switch button. Based on the picture, can you please advise if I can add a fan directly to this exhaust/air duct vent or if I’m required to have an insulation tube leading outside the roof. The house is a flat roof and I don’t have an access point to the attic (or area between my celing and roof). Also, my electrician has sent a few fan suggestions but they are not appealing as they look like attic or laundromat fans. Does anyone have an exhaust fan suggestion that can fit into this vent and appealing (preferably white colored)? The measurements of the vent are 14 inches by height and 13 inches by width. Thank you so much for your support.
Here are some photos of the vent behind the grill: