That's fair. Let me give it a try.
Air and water enter the door cavity all along the window glass. The plastic draught excluder, or "damp proof barrier," is put there to prevent water from attacking the (usually cardboard) backside of the door trim panel which is somewhat exposed through all the door cavity openings, especially when the window is rolled up (like when it is raining!). The benefit of taping the plastic to the door (and taping all around the edge of the plastic) is that air drafts are prevented from entering the passenger cabin via all the cavity openings in the door and thence around the edges of the door panel. Admittedly, this may be less of a problem on a Pagoda than most other cars because of the nice chrome trim pieces secured by all those tiny chrome screws at the front, bottom, and rear of the door trim panel. Most other cars have door trim panels that are just held to the door by a handful of screws or bunch of plastic plugs and have lots of gaps all around the edges. Still, that is the reason why the plastic draught excluder is attached to the door, rather than just to the backside of the door trim panel. There is nothing more annoying than a cold draft of air wafting at your hips or legs on a cold winter day in an otherwise tight car!
- Mike Hughes -ô¿ô-
1966 230SL Auto P/S
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