We were fortunate enough to have a cold snap in december for a few weeks. I had wanted to do this for a long time. We own an inflatable igloo that we use to make snow igloos, but I wanted to try to make an ice igloo by spraying water on it overnight. It was quite a task but the result was beautiful. It got to about 3/4″ thick when I decided to deflate the balloon. Simple LED light for the red glow.