We put weatherstripping on oursThere are a couple of things that stand out to me in these photos. First, there is no weatherstripping on the lid. Heat and moisture will easily escape through the small cracks. Secondly, there is no covering on the doorway. To hold humidity in, and heat, there needs to be a covering on the doorway. I'm sure that a humidifier or mister will help, but until the box is better seal I don't believe that you will be satisfied with the results.