diff --git a/src/Umbraco.Core/Configuration/Models/NuCacheSettings.cs b/src/Umbraco.Core/Configuration/Models/NuCacheSettings.cs
index a2bc7d3561..89a726f30a 100644
--- a/src/Umbraco.Core/Configuration/Models/NuCacheSettings.cs
+++ b/src/Umbraco.Core/Configuration/Models/NuCacheSettings.cs
@@ -2,6 +2,6 @@
 {
     public class NuCacheSettings 
     {
-        public string BTreeBlockSize { get; set; }
+        public int? BTreeBlockSize { get; set; }
     }
 }
diff --git a/src/Umbraco.PublishedCache.NuCache/DataSource/BTree.cs b/src/Umbraco.PublishedCache.NuCache/DataSource/BTree.cs
index ae7393a91a..99d0e9da38 100644
--- a/src/Umbraco.PublishedCache.NuCache/DataSource/BTree.cs
+++ b/src/Umbraco.PublishedCache.NuCache/DataSource/BTree.cs
@@ -45,11 +45,10 @@ namespace Umbraco.Web.PublishedCache.NuCache.DataSource
             var blockSize = 4096;
 
             var appSetting = settings.BTreeBlockSize;
-            if (appSetting == null)
+            if (!appSetting.HasValue)
                 return blockSize;
 
-            if (!int.TryParse(appSetting, out blockSize))
-                throw new ConfigurationErrorsException($"Invalid block size value \"{appSetting}\": not a number.");
+            blockSize = appSetting.Value;
 
             var bit = 0;
             for (var i = blockSize; i != 1; i >>= 1)