On a scamp
19 Deluxe with front bath room, to cool the loft. I got a 4 inch inline duct fan and ran a flexible duct in the loft storage area above the bath room, and have an intake vent in the wall above the bath room door and a vent beside the left side of the storage area door at the rear of the loft. I got the fan on amazon. The fan is over 200 cfm . This fan moves a lot of air and is very quiet. This set up makes a noticeable difference in the loft area. This set up helps heat the loft in cold weather also.