Would This Air Dam Save Heat?

Factual Questions
1

OK, so we have a gas fireplace downstairs in the family room. We also have a large hallway access to it that opens up into a two-story open space as part of the staircase.

If I were to install a plexiglass plate hanging down at the hallway entrance to the family room, would this air dam reduce the air flow to keep some of the heat in the family room instead of rising up through the large open stairwell? I was thinking the air dam would be at least 18-20 inces in height hanging at the hallway entrace to the family room.

I ask this because I see similar glass air dams around escalators in large stores and if it works for them it should work on a small scale in a home.

2

Seems like it would be cheap enough to try and find out. Depending on the frequency of use and internal home preferences, ( wifes opinion ) you might also try long strips that overlap clear to the floor like some wharehouses use.

3

You may wish to use a blind that can be lowered and raised as you wish. You won’t have to deal with a permanent foot and a half visable air damn all the time.