diff --git a/image-builder/image_builder.sh b/image-builder/image_builder.sh
index e18822d842..ceb303e062 100755
--- a/image-builder/image_builder.sh
+++ b/image-builder/image_builder.sh
@@ -374,7 +374,7 @@ create_rootfs_image() {
 	fi
 
 	info "Mounting root partition"
-	readonly mount_dir=$(mktemp -d osbuilder-mount-dir.XXXX)
+	readonly mount_dir=$(mktemp -p ${TMPDIR:-/tmp} -d osbuilder-mount-dir.XXXX)
 	mount "${device}p1" "${mount_dir}"
 	OK "root partition mounted"