diff --git a/build-tools/modify-build-cfg b/build-tools/modify-build-cfg
index 26694a6c..ba235d72 100755
--- a/build-tools/modify-build-cfg
+++ b/build-tools/modify-build-cfg
@@ -95,6 +95,9 @@ fi
 grep -q "config_opts\['chroot_setup_cmd'\] = 'install @buildsys-build pigz lbzip2 yum'" $FILE || \
     echo "config_opts['chroot_setup_cmd'] = 'install @buildsys-build pigz lbzip2 yum'" >> $FILE
 
+# rpmbuild_networking is required for invoking helm commands within mock
+grep -q "config_opts\['rpmbuild_networking'\] = True" $FILE || \
+        echo "config_opts['rpmbuild_networking'] = True" >> $FILE
 #
 # Read macros from tis.macros to add to the build config file,
 # for use in RPM spec files