diff --git a/packages/editor/src/components/editor/selection-manager.tsx b/packages/editor/src/components/editor/selection-manager.tsx
index 76d15055..0680f44b 100755
--- a/packages/editor/src/components/editor/selection-manager.tsx
+++ b/packages/editor/src/components/editor/selection-manager.tsx
@@ -108,6 +108,10 @@ function resolveStairMaterialTarget(
     return 'railing'
   }
 
+  if (hitObjectName.startsWith('stair-side')) {
+    return 'side'
+  }
+
   if (event.materialIndex === 0) {
     return 'tread'
   }