Preparation

• 1). Remove all furnishings, planters, grills and other items from the area.
  
  
• 2). Tape sheets of plastic, or a tarp, on the wall next to the deck or balcony. This prevents the waterproof wood sealant from getting on the wall, cutting down the amount of time cleanup takes. Lay more plastic sheets, or tarps, on the ground surrounding the deck or balcony.
  
  
• 3). Tape sheets of plastic, or a tarp, on the wall under second story balconies. Use a tall ladder to safely reach the area. Have a helper hold the ladder steady while you work. Lay plastic sheeting or a tarp over any items, flowers, bushes and grass located on the ground directly under the balcony.
  
  

Process

• 1). Use a stiff-bristled push broom or regular broom to sweep the wood surface clean of all debris and dirt.
  
  
• 2). Put on work gloves, a face mask and a pair of safety goggles, for your protection. Stop working and follow the manufacturer's instructions if the sealant gets in your eyes, nose or mouth. Seek medical attention as soon as possible.
  
  
• 3). Pour the waterproof sealant into the airless sprayer. Follow all directions, warnings and tips provided by the manufacturers of the sealant and the sprayer.
  
  
• 4). Apply the sealant to the wooden balcony or deck with slow, even sweeps of spray. To waterproof wooden balconies and decks evenly, apply the sealant to small sections at a time. Use the paint roller to spread out waterproof sealant that forms puddles.
  
  
• 5). Dispose of all containers according to local hazardous material regulations. Clean the airless sprayer according to the manufacturer's instructions.
  
  
• 6). Remove plastic sheeting or tarps after the waterproof sealant dries. It typically takes 48 hours for sealant to dry. Do not walk on the area until it is dry.