If you are changing your door hinges, the answer to this question is of course easy. Just replace what you have. If you get a new door then you may have some options. Most standard size hollow doors use a 3 "3.5" hinge. The exterior iron door, like a thermatru insulated stainless steel door, will take 3 4 "hinges most of the time. The best way to check with your local on-site store is to be able to tell you the size and number of hinges you are The doors that need to be supported, you will be installing. Larger than standard doors may require additional or larger door hinges.
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