There seem to be as many ways to hang a door as there are carpenters to hang them, so after many years of running a trim crew, I came up with a few of my own ways to make the work easier and the results better.
When it comes to hanging doors, I believe that the jamb legs should bear fully on the subfloor. Nails alone (especially the light-gauge nails used these days) won’t support the weight of the jamb and door over time. Trimming the jamb legs to closer tolerances requires accurate measuring and cutting techniques. Instead of marking a level line and then measuring each side to determine the length of the jamb legs, I came up with a jig that holds my level and almost immediately tells me the difference in length between the two legs. Of course, this jig works well if I’m installing doors on a finished floor, too.
When the time comes to cut the jambs, I adjust my technique depending on the project. If I’m removing the doors from the jambs before installation, I tack a spreader across the legs to maintain the opening, and I cut with a chopsaw paired with an outfeed stand to support the jamb. More often, I keep the doors and jambs intact, mark the jamb lengths, and cut them with a circular saw and a crosscut jig.
Here’s a look at my jamb-measuring and cutting jigs and some other ideas for fast, accurate, sturdy door-hanging.