diff --git a/wscript b/wscript
index 21a90253b7..bb3b55783f 100644
--- a/wscript
+++ b/wscript
@@ -390,7 +390,9 @@ def _build_recursion(bld):
         common_dirs_patterns,
         excl=common_dirs_excl,
     )
-    dirs_to_recurse.append('libraries/AP_IOMCU/iofirmware')
+    if bld.env.IOMCU_FW is not None:
+        if bld.env.IOMCU_FW:
+            dirs_to_recurse.append('libraries/AP_IOMCU/iofirmware')
     for p in hal_dirs_patterns:
         dirs_to_recurse += collect_dirs_to_recurse(
             bld,