What It Means This Shaw hardwood is approved for installation over water type radiant heated subfloors. Floating installation method only. Direct glue-down is NOT recommended! This Shaw hardwood meets the GREENGUARD indoor air quality requirements and is GREENGUARD Certified. This Shaw hardwood is Cradle to CradleCM Silver Certified. This Shaw Epic® hardwood is made with Shaw’s EnviroCore® and provides unsurpassed structural integrity, impact resistance and dimensional stability. Highly photosensitive and will amber with exposure to light. Installation Grade This Shaw product can be installed above, on or below ground level. This Shaw product can be installed above and on ground level.