I tried to covered my son's bedroom skylight with cardboard too. But just holding under the space for few minutes to get the measurements the board got so hot! Just wounding is it safe using the cardboard? How was your experience with it?
I only used carboard for a couple of days, and then replaced it with some 1/8" thick plywood. I don't think heat would be an issue but better safe than sorry, thanks for bringing this to our attention!
