diff --git a/build_image b/build_image
index a9f54ecf99..5ea08da4b2 100755
--- a/build_image
+++ b/build_image
@@ -12,6 +12,11 @@
 SCRIPT_ROOT=$(dirname $(readlink -f "$0"))
 . "${SCRIPT_ROOT}/common.sh" || exit 1
 
+# Script must run inside the chroot
+restart_in_chroot_if_needed "$@"
+
+assert_not_root_user
+
 # Developer-visible flags.
 DEFINE_string board "${DEFAULT_BOARD}" \
   "The board to build an image for."
diff --git a/image_to_vm.sh b/image_to_vm.sh
index 37d25de020..585f02abe4 100755
--- a/image_to_vm.sh
+++ b/image_to_vm.sh
@@ -8,10 +8,15 @@
 # disk image, supporting a variety of different targets.
 
 
-
 # Helper scripts should be run from the same location as this script.
 SCRIPT_ROOT=$(dirname "$(readlink -f "$0")")
 . "${SCRIPT_ROOT}/common.sh" || exit 1
+
+# Script must run inside the chroot
+restart_in_chroot_if_needed "$@"
+
+assert_not_root_user
+
 . "${BUILD_LIBRARY_DIR}/toolchain_util.sh" || exit 1
 . "${BUILD_LIBRARY_DIR}/build_image_util.sh" || exit 1
 . "${BUILD_LIBRARY_DIR}/vm_image_util.sh" || exit 1