There is no restraint to an exterior door with the exception of a good weather-resistant wood. We have come across exterior doors of all shapes and sizes. The modern thickness of an exterior door is 1 3/4" however we have seen early exterior doors that are as thin as 1 1/8" to turn of the century doors that are as much as 2 1/4" thick. If you are seeking a specific type of exterior door please use the "contact" button above to give us a description of the door you seek and we will get back to you as soon as possible.