Love the walls, did the white side towards my grow, the silver side gets tore ez, n is a huge oita ass to clean, so white side it is. I did studs, r tech, gap foam, plastic with liq nail, the reg insulation rolls. 98% air tight. Did it to keeps dust bugs n disease out, plus helps me keep air in and out where i want not thru leak. Had to make sure fresh air in crosses the whole way across the room n not leaking by the filter from the cracks n the build..