diff --git a/lib/cartodb/models/mapconfig/adapter/mapconfig-buffer-size-adapter.js b/lib/cartodb/models/mapconfig/adapter/mapconfig-buffer-size-adapter.js
index 3296d0ea..7e9e93a1 100644
--- a/lib/cartodb/models/mapconfig/adapter/mapconfig-buffer-size-adapter.js
+++ b/lib/cartodb/models/mapconfig/adapter/mapconfig-buffer-size-adapter.js
@@ -9,8 +9,13 @@ MapConfigBufferSizeAdapter.prototype.getMapConfig = function (user, requestMapCo
         return callback(null, requestMapConfig);
     }
 
+
     this.formats.forEach(function (format) {
         if (Number.isFinite(context.templateParams.buffersize[format])) {
+            if (requestMapConfig.buffersize === undefined) {
+                requestMapConfig.buffersize = {};
+            }
+
             requestMapConfig.buffersize[format] = context.templateParams.buffersize[format];
         }
     });
diff --git a/test/acceptance/buffer-size-format.js b/test/acceptance/buffer-size-format.js
index 15be2e66..c32f62d1 100644
--- a/test/acceptance/buffer-size-format.js
+++ b/test/acceptance/buffer-size-format.js
@@ -283,7 +283,7 @@ describe('buffer size per format for named maps', function () {
 });
 
 
-describe.only('buffer size per format for named maps w/o placeholders', function () {
+describe('buffer size per format for named maps w/o placeholders', function () {
     var testCases = [
         {
             desc: 'should get png tile using buffer-size 0 overriden by template params',
@@ -398,7 +398,8 @@ describe.only('buffer size per format for named maps w/o placeholders', function
             }
         },
         {
-            desc: 'should get png tile using buffer-size 0 overriden by template params with no buffersize in mapconfig',
+            desc: 'should get png tile using buffer-size 0' +
+                  ' overriden by template params with no buffersize in mapconfig',
             coords: { z: 7, x: 64, y: 48 },
             format: 'png',
             placeholders: {