diff --git a/R/check.R b/R/check.R
index 50012d4..368614a 100644
--- a/R/check.R
+++ b/R/check.R
@@ -68,7 +68,8 @@ check_task <- function(state, task) {
 
 check_env_vars <- function(check_version = FALSE, force_suggests = FALSE) {
   c(
-    "R_ENVIRON_USER" = tempfile(),
+    "R_ENVIRON_USER" = tempdir(),
+    "R_LIBS" = "",
     # Switch off expensive check for package version
     # https://github.com/hadley/devtools/issues/1271
     if (getRversion() >= "3.4.0" && as.numeric(R.version[["svn rev"]]) >= 70944) {