diff --git a/source/build/src/engine.cpp b/source/build/src/engine.cpp
index 9db266cb6..d6f8d8f71 100644
--- a/source/build/src/engine.cpp
+++ b/source/build/src/engine.cpp
@@ -11101,7 +11101,7 @@ void updatesectorz(int32_t x, int32_t y, int32_t z, int16_t *sectnum)
         if (inside_z_p(x,y,z, i))
             SET_AND_RETURN(*sectnum, i);
 
-    *sectnum = -1;
+    updatesector(x, y, sectnum);
 }