How to secure shoe moulding against metal frame

Question

A wall of our home has floor-to-ceiling windows and an integrated sliding door. The wood flooring butts-up directly against the metal frames of these windows and door. Though the flooring was cut very accurately to align with the frames (minimal gap) it still looks a bit unfinished without some sort of trim. Additionally, parts of the metal frame are prone to condensation in the winter and I would like to create a barrier that helps prevent any drips of water from running down the metal all the way to the sub-floor.

My thinking was that a simply strip of shoe molding, with a thorough poly top coat, could be used. Here's the the area with the molding before being slid into place:

And now with the molding in place:

What I don't know is how to secure and seal this molding. It should be secured to the wall to allow room for expansion of the flooring, but I do not think it's feasible to nail/glue into a metal frame. Would it be problematic to nail/glue directly to the flooring in this situation? Additionally, is there an appropriate way to "seal" the gap between the molding and metal frame, such as a silicon-based caulk? The pictures above actually show the condensation drips that I am worried about traveling beneath the flooring. If this condensation eventually does cause damage I'd rather it be isolated to the molding then getting into the flooring/sub-flooring.

Answer 1

The only option is to nail it to the floor. If you attach it to the door frame, it will be too flimsy.

You could try an epoxy sealant, but water will get in anyway. Preventing water ingress requires a structure that is designed for it.

I wouldn't worry about condensation. Normally, its only when you have a steady flow of water that there is a problem.

Caulk will not do anything. Sometimes at the marina I see funny boats where the owner thinks they can keep out water with caulk. They get a leaky window because they have a sucky boat, so they get the idea in their head that all they have to do is seal the window with caulk. The leak continues. So, they reason they need to use more caulk. You can guess where this is headed. Soon, the boat looks like it should be renamed "Count Caulkula".