diff --git a/documentation/usage-guide/Makefile b/documentation/usage-guide/Makefile
index 4316687b77278535b6bce7fd4822ed5099ab8cc9..eee953ab312ae330f79cdba2e8b877f357be33ad 100644
--- a/documentation/usage-guide/Makefile
+++ b/documentation/usage-guide/Makefile
@@ -16,7 +16,7 @@ help:
 .PHONY: help Makefile
 
 html-watch:
-	@$(SPHINXAUTOBUILD) "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+	@$(SPHINXAUTOBUILD) "$(SOURCEDIR)" "$(BUILDDIR)/html" $(SPHINXOPTS) $(O)
 
 # Catch-all target: route all unknown targets to Sphinx using the new
 # "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).