Installing an Interior Door?

Question

Hi all DIYers, I'll be attempting my first interior door replacement and have a couple of questions. I'm replacing the door only and using the existing jamb. If I buy a prehung door (and discard the jamb it comes with) will the door line up with the existing jamb? I guess what I"m asking is really are there standards? I know the striking plate measures 43' from the top. Will it be the same distance on the prehung door? Also the hinge placement ... will they be the same as well. The door is a standard width (32') but I'm going to have to make a cut as it's only 79.5' tall. Do I shave the 1/2 inch off the bottom or the top? Any help or suggestions would be greatly appreciated. Thanks in advance.

Answer 1

Obviously you don`t want to disturb the original opening for some reason. In answer to your main question, you should typically have 3/4 to 7/8 inch of rail at the bottom of your slab. Upon examination you`ll probably find the old one was also cut for some reason. If you can find a prehung off the shelf that matches your hinge placement, you better buy a lotto ticket, because you are very lucky!! Best bet if original has a good operating margin,use it as a template on a new slab. Also check your new slab. Some have a designated hinge side. Happy Hunting!!!!

Answer 2

It will be cheaper to buy a blank door or just the slab, as it's called. Depending on the style of door you have, flat, flush, 6-panel, etc., you probably won't want to try and use a pre-hung. Chances are the mortising won't line up for the hinges or the striker plate. If you buy a slab, set it on top of the old one once you remove it and use a square to align the hinges and center for the striker. Then get a chisel and go to town. I'd check all my measurements several times before actually doing any cutting on the door. Check width, height, thickness. Double check the measurements against the existing jamb opening also. Make sure your jamb is plumb too. It's not the easiest thing in the world to retro-fit a new door in an old jamb. but completely do-able. Just have a little patience. Make sure you have the correct tools. Remember: Measure twice, cut once! Good Luck.

Answer 3

The pre-hung door is supposed to be standard size, hinge placement, and lockset placement. Unfortunately this hasn't helped me any when trying to do what you are. Out of 300+ doors probably 30 have matched up. You would be better off just replacing the old door completely with a new pre-hung. As for cutting the door off be careful, if it is what is called a hollow core door you only have 3/4 of an inch of material on the top edge and about 1 inch along the bottom edge to work with. Cutting too much on either can cause the door to literally fall apart. Try checking around your area for a custom door manufacturer. All of the can make a door that will fit exactly as you need. And most are the same price or cheaper the most hardware stores.

Answer 4

You can buy the pre-hung door, but isn't that more expensive than just the door by itself? I believe it is, and if you're going to discard it anyway, there's no sense in doing that.

If the strike plate is 43" from the top and you plane the top of the door, it will now be less than 43" and it won't line up anymore. Doors are extra tall because the standards have changed over the years and this allows you to plane from the top or the bottom in order for your strike plate to line up. That is what's paramount here.

Answer 5

If you buy a prehung door you have to change all the door casing molding.I always recommend a prehung door,it's just faster to install.If you buy a slab door you have to plane it and router out for the hinges and they never fit square in the old door frame.