28" pre hung interior door istall question.
#1
03-02-06, 05:30 AM
28" pre hung interior door istall question.
Hello, I'm about to install a 28" prehung door. The door calls for a RO of 30.5". I have a RO of 30.25" and this still leaves me with a lot to shim, about 3/4 to 1". Is this the norm or should I trim it down some with some plywood? Thanks for the help.
John
John
#2
03-02-06, 05:37 AM
Group Moderator
It sounds like your rough opening is the perfect size. It allows room for the door to be plumbed and shimmed on each side (centered in the rough opening). You would only have a 3/4" gap if you nailed the door tight to one side. You don't usually do that because it's a "rough" opening- there's no guarantee that the framing is as plumb as you'd like the door to be.
I usually nail a few shims onto the hinge side before installing the door. I plumb the shims with a 6ft level so they are perfectly plumb then put the door in and tack the hinge side to the shims as a starting point. Hope that tip helps.
I usually nail a few shims onto the hinge side before installing the door. I plumb the shims with a 6ft level so they are perfectly plumb then put the door in and tack the hinge side to the shims as a starting point. Hope that tip helps.
#3
03-02-06, 06:17 AM
XSleeper, thanks. With that size gap do you ever have problems when nailing in the door, like the frame twisting a little? thanks,
John
John
#4
03-02-06, 04:45 PM
I won't steal xsleeper's thunder, but generally when framing, we leave 2 1/2" more than the proposed door unit to be installed. I like to know the swing of the door prior to framing so special care can be taken to ensure the hinge studs are almost perfectly plumb. So the gap you have is ok. On the latch side, you will use shims inserted in opposing fashion so they form a flat surface so you can nail right through them. That way the door is in firmly, and it won't tend to warp as you stated. Trim the shims off flush with the frame and install the case molding.
#5
03-03-06, 07:02 PM
Group Moderator
No, no problems. As Chandler mentioned, you take 2 shims, turn them opposite directions so that they form a rectangle, then just slide them past one another until you get the right thickness, then tack the door in place through the shims.
The only thing you may need to watch for is twisted framing, because if you have twisted framing, you need to shim it a little differently to compensate. When you use air powered finish nailers, they don't really pull the jamb or twist it- they simply hold it in place. Some people shoot doors in without shims at all, leaving them hang in mid-air with only the nails and casing holding them in place. That's a poor method, in my opinion.
The only thing you may need to watch for is twisted framing, because if you have twisted framing, you need to shim it a little differently to compensate. When you use air powered finish nailers, they don't really pull the jamb or twist it- they simply hold it in place. Some people shoot doors in without shims at all, leaving them hang in mid-air with only the nails and casing holding them in place. That's a poor method, in my opinion.
