Use galvanized drywall screws to attach the green board to the wall studs. Coat the green board with water-based urethane before you start to finish the green board. I've had great success using this green board drywall behind sinks, toilets and on walls with ceramic tile backsplashes. Greenboard's paper cover is a sea-foam green on one side. The color imparts no special water-resisting properties, but it does serve two purposes. For one, it identifies this as moisture-friendly drywall. For another, it helps the installer better see where to apply the drywall compound. Q. How is "green board" different from regular drywall?Where is it supposed to be used, and what are its limitations? A.Mike Lynn of United States Gypsum Company's Research and Technology Center responds: Green board, so called because of its green facing paper, is a water-resistant gypsum panel intended as a base for the application of ceramic tile and plastic-faced wall panels. I did find this quote under a basic google search when I looked up green board "NOTE: Green board is water resistant – it is not water-proof. Green board is highly efficient in bathrooms and kitchens where moisture is frequently in the air, but it is not the drywall that should be set behind tile in your shower surround or any other areas ... Greenboard is paper-backed drywall that has a light green "hospital" tint. Greenboard is often used for high-moisture areas such as showers, in which the greenboard is heavily coated with bathroom-quality paint or with cement board on top. Water resistant drywall is usually made with green paper, and is accordingly called “green board.” Green board comes with an oil-based additive in the paper layer that keeps water from rotting the gypsum. There are also soundproof drywall products available, as well as more eco-friendly drywall made from recycled building materials.