Ideas for a converting a closet into a walk-in?

[themoneycollector]

Some ideas I'm researching.
1). Replace dry-wall with moisture and vapor barrier.
2). Would have to remove carpeting inside the bathroom
3). Seal the door
4). Active temperature and humidity control
5). I wouldn't line the closet with spanish cedar. But instead make some spanish cedar shelving only.

The first three seem fairly straightforward. But the humidity/temp is where the bulk of the planning and costs would be. The temp requires venting and adequate power. The humidity needs to overcome the humidity drop from the temperature device and also has its power needs.

For temp, there are several options:
1). A large TE unit made for wine cellars. Cost is high.
2). A window air conditioner. Cost is low. The closet has one side open to a room, one side is the brick exterior. I could either vent to exterior outside the brick, or vent to the attic, or all the way up out the roof. I'm not sure which would be better and for what reason. It will likely interfere with the humidity, so I need to see if I can counter that with the humidification.