diff --git a/lib/cartodb/server_options.js b/lib/cartodb/server_options.js
index 80c2521d..4938c709 100644
--- a/lib/cartodb/server_options.js
+++ b/lib/cartodb/server_options.js
@@ -22,7 +22,8 @@ module.exports = function(){
         grainstore: {
           datasource: global.environment.postgres,
           cachedir: global.environment.millstone.cache_basedir,
-          mapnik_version: global.environment.mapnik_version || mapnik.versions.mapnik
+          mapnik_version: global.environment.mapnik_version || mapnik.versions.mapnik,
+          default_layergroup_ttl: 300 // seconds
         },
         mapnik: {
           metatile: rendererConfig.metatile,