diff --git a/lib/manager/npm/post-update/lerna.js b/lib/manager/npm/post-update/lerna.js
index 09b6538359d2eb45f83fed28d9ac0298d1c0ad0f..1b2fe87a819997332e195c93c4d7127c713a4d0d 100644
--- a/lib/manager/npm/post-update/lerna.js
+++ b/lib/manager/npm/post-update/lerna.js
@@ -34,10 +34,10 @@ async function generateLockFiles(
     logger.debug('Using lerna version ' + lernaVersion);
     let params;
     if (lernaClient === 'npm') {
-      if (skipInstalls) {
-        params = '--package-lock-only --no-audit';
-      } else {
+      if (skipInstalls === false) {
         params = '--ignore-scripts  --no-audit';
+      } else {
+        params = '--package-lock-only --no-audit';
       }
     } else {
       params =
diff --git a/lib/manager/npm/post-update/npm.js b/lib/manager/npm/post-update/npm.js
index 9c6dc96d0691298c1f6369002d9fa7bc26a0dfc3..7a4d89c1f88eeb5a3ff68c8136fa17c0268135c7 100644
--- a/lib/manager/npm/post-update/npm.js
+++ b/lib/manager/npm/post-update/npm.js
@@ -64,10 +64,10 @@ async function generateLockFile(
       cmd = 'npm';
     }
     args = `install`;
-    if (skipInstalls) {
-      args += ' --package-lock-only --no-audit';
-    } else {
+    if (skipInstalls === false) {
       args += ' --ignore-scripts --no-audit';
+    } else {
+      args += ' --package-lock-only --no-audit';
     }
     logger.debug(`Using npm: ${cmd} ${args}`);
     // TODO: Switch to native util.promisify once using only node 8