diff --git a/rail_cmd.c b/rail_cmd.c
--- a/rail_cmd.c
+++ b/rail_cmd.c
@@ -374,7 +374,7 @@ int32 CmdBuildSingleRail(int x, int y, u
 				break;
 			}
 
-			if (IsLevelCrossing(tile) == 0x10 && (m5 & 0x08 ? 1 : 2) == rail_bit)
+			if (IsLevelCrossing(tile) && (m5 & 0x08 ? 1 : 2) == rail_bit)
 				return_cmd_error(STR_1007_ALREADY_BUILT);
 			/* FALLTHROUGH */