diff --git a/tools/docs/sphinx-build-wrapper b/tools/docs/sphinx-build-wrapper
index 2c63d28f639d..1bb962202784 100755
--- a/tools/docs/sphinx-build-wrapper
+++ b/tools/docs/sphinx-build-wrapper
@@ -238,7 +238,12 @@ class SphinxBuilder:
             self.latexopts = os.environ.get("LATEXOPTS", "")
 
         if not verbose:
-            verbose = bool(os.environ.get("KBUILD_VERBOSE", "") != "")
+            try:
+                verbose = bool(int(os.environ.get("KBUILD_VERBOSE", 0)))
+            except ValueError:
+                # Handles an eventual case where verbosity is not a number
+                # like KBUILD_VERBOSE=""
+                verbose = False
 
         if verbose is not None:
             self.verbose = verbose
diff --git a/tools/lib/python/kdoc/kdoc_files.py b/tools/lib/python/kdoc/kdoc_files.py
index 2428cfc4e843..ed82b6e6ab25 100644
--- a/tools/lib/python/kdoc/kdoc_files.py
+++ b/tools/lib/python/kdoc/kdoc_files.py
@@ -238,7 +238,12 @@ class KernelFiles():
         """
 
         if not verbose:
-            verbose = bool(os.environ.get("KBUILD_VERBOSE", 0))
+            try:
+                verbose = bool(int(os.environ.get("KBUILD_VERBOSE", 0)))
+            except ValueError:
+                # Handles an eventual case where verbosity is not a number
+                # like KBUILD_VERBOSE=""
+                verbose = False
 
         if out_style is None:
             out_style = OutputFormat()