diff --git a/src/renderers/shaders/ShaderLib.js b/src/renderers/shaders/ShaderLib.js
index 59df621f21ed71..0eb045a995d6ec 100644
--- a/src/renderers/shaders/ShaderLib.js
+++ b/src/renderers/shaders/ShaderLib.js
@@ -299,7 +299,7 @@ ShaderLib.physical = {
 			sheen: { value: 0 },
 			sheenColor: { value: new Color( 0x000000 ) },
 			sheenColorMap: { value: null },
-			sheenRoughness: { value: 0 },
+			sheenRoughness: { value: 1 },
 			sheenRoughnessMap: { value: null },
 			transmission: { value: 0 },
 			transmissionMap: { value: null },
@@ -309,7 +309,7 @@ ShaderLib.physical = {
 			thicknessMap: { value: null },
 			attenuationDistance: { value: 0 },
 			attenuationColor: { value: new Color( 0x000000 ) },
-			specularIntensity: { value: 0 },
+			specularIntensity: { value: 1 },
 			specularIntensityMap: { value: null },
 			specularColor: { value: new Color( 1, 1, 1 ) },
 			specularColorMap: { value: null },