Midrexâs primary business is direct reduction ironmaking. We build DRI plants that work day in and day out, year after. year to provide value for our clients so that they can make. the most of their investment and maximize their profits for. years to come. The MIDREXÂ® Process 2. The MIDREXÂ® Process.
Quick Answer. The maximum interior height of an entry door threshold is 1/2 inch, and up to 3/4 inch on exterior siding doors where it is essential to keep water out, as stated by the United States Access Board. These height limits improve wheelchair access to buildings.
Standard door sizes start at 1 foot 6 inches and are offered at 2-inch increases to 3-feet wide. Fitting with standard door openings, stock door heights are 6 feet 8 inches; 7 feet; and 8 feet. If you live in an older house or have an unusual door opening, there are manufacturers who offer custom sizes. Doors are also available in a variety of colors.