Porch enclosures, window grilles and security enclosures available from Trellidor Trellidor Australia Porch enclosures, window grilles and security enclosures are available from Trellidor . The company has a range of security doors including Steel Fencing. Porch enclosures are manufactured from galvanized steel and have a powder coated finish, in colours to suit the residence. Trellidor patent security door and expanding doors offers an extensive range of quality Expending trellis doors products including security windows