diff --git a/vnavmesh/Navmesh.cs b/vnavmesh/Navmesh.cs
index 487ec13..4d84486 100644
--- a/vnavmesh/Navmesh.cs
+++ b/vnavmesh/Navmesh.cs
@@ -11,7 +11,7 @@ namespace Navmesh;
 public record class Navmesh(int CustomizationVersion, DtNavMesh Mesh, VoxelMap? Volume)
 {
     public static readonly uint Magic = 0x444D564E; // 'NVMD'
-    public static readonly uint Version = 16;
+    public static readonly uint Version = 17;
 
     // throws an exception on failure
     public static Navmesh Deserialize(BinaryReader reader, int expectedCustomizationVersion)
diff --git a/vnavmesh/SceneExtractor.cs b/vnavmesh/SceneExtractor.cs
index d67835c..2b7bd06 100644
--- a/vnavmesh/SceneExtractor.cs
+++ b/vnavmesh/SceneExtractor.cs
@@ -116,10 +116,8 @@ public unsafe SceneExtractor(SceneDefinition scene)
         foreach (var coll in scene.Colliders)
         {
             // try to filter out all colliders that become inactive under normal conditions
-            // auto-opening doors seem to all have material type 0x7400
-            // the transparent purple wall that surrounds the party before "duty commenced" in an instance has material type 0x6400
-            // however, invisible walls that surround a lot of overworld zones (like southern thanalan) have material type 0x202411, so we can't test just for 0x400
-            if ((coll.matId & 0x6400) == 0x6400)
+            // this is basically every material with 0x400 set, except for the invisible walls that surround most overworld zones, which are 0x202411
+            if ((coll.matId & 0x410) == 0x400)
                 continue;
 
             var info = ExtractColliderInfo(scene, coll.key, coll.transform, coll.crc, coll.type);