dull

  1. Y

    Silver side of foam board ok or Mylar?

    I make a new grow box 3x3x6. I used the foam board insulation and the shiny side is facing in. I'm wondering if that's enough or should I put mylar film on the inside? I seen a comment somewhere that the dull side of aluminum foil reflects more light than the shiny side.which is hard for me to...