In addition to the places I've documented before that were found in my 315RLTS, the recent Foam Desk Project revealed more openings in the floor. These are under where the side stands were located. The best way to seal them (without tearing apart the side stands) is from underneath. The picture below should be self-explanatory. Find the opening under your trailer and seal it up.
For reference the floorplan for the 315RLTS is below with the area of concern circled. If your trailer has a similar setup, you'll likely find the same hole in the floor (both sides).
For reference the floorplan for the 315RLTS is below with the area of concern circled. If your trailer has a similar setup, you'll likely find the same hole in the floor (both sides).