Mark the position of the latch opening(s) on the door by measuring the frame from the top and bottom, and remember to allow for the clearance.
After determining all of the measurements and options needed for the door, it can then be ordered and installed. Find out the availability of the door and the time required to obtain it. Usually, the replacement door is needed as soon as possible.
Note: You may want to get in touch with several door companies before you actually need a door. Get some brochures, find out about delivery times and warranties.
A properly ordered and installed door can last a lifetime.
For more information, contact your locksmith wholesaler. If they do not sell hollow metal doors and frames, ask for a recommendation or contact a door company and find out through whom you can purchase door and/or frames. Many door companies offer information on how to measure for a frame as well as a door. Remember: When ordering a door or frame, find out who pays for shipping.