Application Directions

• Before You Begin
  • This product is corrosive. Handle with care.
  • A trial patch is recommended before starting. Test on an inconspicuous area before applying to entire surface.
  • Product can be applied to dry or damp wood.
  • Avoid spraying on windy days.
  • Prior to spraying, close all windows and doors around area in which you are working.
  • Remove all deck furniture and decorative items that could come in contact with Thompson's® WaterSeal® Heavy Duty Deck Cleaner. Do not allow product to come in contact with aluminum, painted, or finished surfaces that you do not intend to restore.
  • Saturate the ground around plants and shrubs with fresh water prior to application. Then cover all plants and shrubs to protect them from overspray. Uncover promptly after use.
  • Wear a long-sleeved shirt, pants, eye protection and rubber gloves. Do not allow Thompson's® WaterSeal® Heavy Duty Deck Cleaner to come in prolonged contact with clothing, carpet or fabric as damage may occur.
  • Thompson's® WaterSeal® Heavy Duty Deck Cleaner may slightly darken redwood. To brighten wood after cleaning, use Thompson's® WaterSeal® Deck Cleaner & Brightener.
  • Plan the application: for horizontal surfaces, work backwards so that you do not walk on the surface being treated. For vertical surfaces, work from the bottom up. Treat small areas at a time.
  • Exercise caution when working on wet surfaces, as they tend to be slippery.
• Application
  • Add contents of container to a plastic bucket or plastic pump-up sprayer. Do not use a metal container.
  • For ease of application, apply Thompson's® WaterSeal® Heavy Duty Deck Cleaner with a pump-up sprayer, or use a synthetic bristle brush or roller. If you are using a pump-up sprayer, use a coarse spray. Do not breathe spray mist.
  • Do not apply to an area larger than you can work on within 10-15 minutes. Immediately and thoroughly rinse any overspray or accidental spills with water.
  • Wait 10-15 minutes and then scrub the surface with a synthetic, stiff bristle brush (do not use a wire or natural bristle brush) to remove any stain or finish that does not immediately come up. Do not let Thompson's® WaterSeal® Heavy Duty Deck Cleaner completely dry during application. If it does dry, re-wet surface with a garden hose. Keep the brush wet to help in cleaning.
  • If stubborn areas remain, repeat the application in those areas.
  • Thoroughly rinse the surface with a garden hose or pressure washer, removing all residue. After rinsing the surface, be sure to saturate the ground around plants and shrubs with fresh water.
• Dry Time
  • Wait 2-3 days, depending on weather conditions, for the wood to dry thoroughly before applying a Thompson's® WaterSeal® oil-based waterproofer or stain. 
  • Depending on weather conditions, allow wood to dry thoroughly for 2-3 days before applying a wood sealer or waterproofer.
• CAUTIONS
  CAUTIONS: Contains Sodium Metasilicate. Do not allow contact with eyes and skin. Wear safety glasses and rubber gloves when handling and during application. If material contacts skin, immediately wash with soap and water. Use only with adequate ventilation. To avoid overexposure, ensure fresh air entry during handling and application. Avoid breathing mist. If you experience eye watering, headaches, or dizziness, increase fresh air, or wear respiratory protection (NIOSH approved) or leave the area. Keep container closed when not in use. Do not transfer contents to other containers for storage. FIRST AID: In case of eye contact, immediately flush eyes with water for at least 15 minutes. Get medical attention. For skin contact, wash thoroughly with soap and water. In case of respiratory difficulty, provide fresh air and call physician. If swallowed, do not induce vomiting. Call Poison Control Center, hospital emergency room, or physician immediately. DO NOT TAKE INTERNALLY. KEEP OUT OF THE REACH OF CHILDREN. DANGER! CAUSES EYE, SKIN AND RESPIRATORY TRACT BURNS. HARMFUL OR FATAL IF SWALLOWED.