diff --git a/src/window.c b/src/window.c
index bbcdbeb..0a0f8ee 100644
--- a/src/window.c
+++ b/src/window.c
@@ -3951,8 +3951,17 @@ lowerWindow (CompWindow *w)
 {
     XWindowChanges xwc;
     int		   mask;
+    CompWindow     *sibling;
 
-    mask = addWindowStackChanges (w, &xwc, findLowestSiblingBelow (w));
+    if (w->type & CompWindowTypeDesktopMask)
+    {
+	/* desktop windows always should be at the bottom */
+	sibling = NULL;
+    }
+    else
+	sibling = findLowestSiblingBelow (w);
+
+    mask = addWindowStackChanges (w, &xwc, sibling);
     if (mask)
 	configureXWindow (w, mask, &xwc);
 }