diff --git a/opendm/dem/ground_rectification/io/las_io.py b/opendm/dem/ground_rectification/io/las_io.py
index c79a3898..91a7d362 100755
--- a/opendm/dem/ground_rectification/io/las_io.py
+++ b/opendm/dem/ground_rectification/io/las_io.py
@@ -23,7 +23,9 @@ def read_cloud(point_cloud_path):
     blue = arrays["Blue"]
 
     cloud = PointCloud.with_dimensions(x, y, z, classification, red, green, blue)
-    cloud.add_dimension(UserDataDimension(), arrays["UserData"])
+
+    if "UserData" in arrays.dtype.names:
+        cloud.add_dimension(UserDataDimension(), arrays["UserData"])
 
     return pipeline.metadata["metadata"]["readers.las"], cloud
 
@@ -65,7 +67,9 @@ def write_cloud(metadata, point_cloud, output_point_cloud_path):
     arrays['Red'] = red.astype(np.uint8).ravel()
     arrays['Green'] = green.astype(np.uint8).ravel()
     arrays['Blue'] = blue.astype(np.uint8).ravel()
-    arrays['UserData'] = point_cloud.extra_dimensions["UserData"].ravel()
+
+    if "UserData" in point_cloud.extra_dimensions:
+        arrays['UserData'] = point_cloud.extra_dimensions["UserData"].ravel()
 
     writer_pipeline = {
         "pipeline": [