diff --git a/src/DotRecast.Detour.TileCache/DtTileCache.cs b/src/DotRecast.Detour.TileCache/DtTileCache.cs
index 6423305..26fce63 100644
--- a/src/DotRecast.Detour.TileCache/DtTileCache.cs
+++ b/src/DotRecast.Detour.TileCache/DtTileCache.cs
@@ -53,8 +53,6 @@ namespace DotRecast.Detour.TileCache
         private readonly List<DtObstacleRequest> m_reqs = new List<DtObstacleRequest>();
         private readonly List<long> m_update = new List<long>();
 
-        private readonly DtTileCacheBuilder builder = new DtTileCacheBuilder();
-
         public DtTileCache(DtTileCacheParams option, DtTileCacheStorageParams storageParams, DtNavMesh navmesh, IRcCompressor tcomp, IDtTileCacheMeshProcess tmprocs)
         {
             m_params = option;
diff --git a/src/DotRecast.Detour.TileCache/DtTileCacheBuilder.cs b/src/DotRecast.Detour.TileCache/DtTileCacheBuilder.cs
index d73905c..6c5d059 100644
--- a/src/DotRecast.Detour.TileCache/DtTileCacheBuilder.cs
+++ b/src/DotRecast.Detour.TileCache/DtTileCacheBuilder.cs
@@ -29,11 +29,12 @@ using DotRecast.Recast;
 
 namespace DotRecast.Detour.TileCache
 {
-    public class DtTileCacheBuilder
+    public static class DtTileCacheBuilder
     {
         public const int DT_TILECACHE_NULL_AREA = 0;
         public const int DT_TILECACHE_WALKABLE_AREA = 63;
         public const int DT_TILECACHE_NULL_IDX = 0xffff;
+
         private static readonly int[] DirOffsetX = { -1, 0, 1, 0, };
         private static readonly int[] DirOffsetY = { 0, 1, 0, -1 };
 
diff --git a/src/DotRecast.Detour.TileCache/DtTileCacheLayerBuilder.cs b/src/DotRecast.Detour.TileCache/DtTileCacheLayerBuilder.cs
index bd172d1..674b680 100644
--- a/src/DotRecast.Detour.TileCache/DtTileCacheLayerBuilder.cs
+++ b/src/DotRecast.Detour.TileCache/DtTileCacheLayerBuilder.cs
@@ -100,7 +100,6 @@ namespace DotRecast.Detour.TileCache
             List<byte[]> result = new List<byte[]>();
             if (lset != null)
             {
-                DtTileCacheBuilder builder = new DtTileCacheBuilder();
                 for (int i = 0; i < lset.layers.Length; ++i)
                 {
                     RcHeightfieldLayer layer = lset.layers[i];
diff --git a/src/DotRecast.Detour.TileCache/Io/DtTileCacheWriter.cs b/src/DotRecast.Detour.TileCache/Io/DtTileCacheWriter.cs
index 2268263..14438d5 100644
--- a/src/DotRecast.Detour.TileCache/Io/DtTileCacheWriter.cs
+++ b/src/DotRecast.Detour.TileCache/Io/DtTileCacheWriter.cs
@@ -28,7 +28,6 @@ namespace DotRecast.Detour.TileCache.Io
     public class DtTileCacheWriter : DtWriter
     {
         private readonly DtNavMeshParamWriter paramWriter = new DtNavMeshParamWriter();
-        private readonly DtTileCacheBuilder builder = new DtTileCacheBuilder();
         private readonly IDtTileCacheCompressorFactory _compFactory;
 
         public DtTileCacheWriter(IDtTileCacheCompressorFactory compFactory)