diff --git a/src/object_cmd.cpp b/src/object_cmd.cpp
--- a/src/object_cmd.cpp
+++ b/src/object_cmd.cpp
@@ -205,7 +205,8 @@ CommandCost CmdBuildObject(TileIndex til
 {
 	CommandCost cost(EXPENSES_PROPERTY);
 
-	ObjectType type = (ObjectType)GB(p1, 0, 8);
+	ObjectType type = (ObjectType)GB(p1, 0, 16);
+	if (type >= NUM_OBJECTS) return CMD_ERROR;
 	uint8 view = GB(p2, 0, 2);
 	const ObjectSpec *spec = ObjectSpec::Get(type);
 	if (!spec->IsAvailable()) return CMD_ERROR;
diff --git a/src/object_type.h b/src/object_type.h
--- a/src/object_type.h
+++ b/src/object_type.h
@@ -24,7 +24,7 @@ static const ObjectType OBJECT_HQ       
 static const ObjectType NUM_OBJECTS_PER_GRF = 255;    ///< Number of supported objects per NewGRF; limited to 255 to allow extending Action3 with an extended byte later on.
 
 static const ObjectType NEW_OBJECT_OFFSET   =   5;    ///< Offset for new objects
-static const ObjectType NUM_OBJECTS         = 256;    ///< Number of supported objects overall
+static const ObjectType NUM_OBJECTS         = 64000;  ///< Number of supported objects overall
 static const ObjectType INVALID_OBJECT_TYPE = 0xFFFF; ///< An invalid object
 
 /** Unique identifier for an object. */