18 Feb 2008 04:19:19 | Mike Merisko
How To Install A Prehung Door
Hanging a door these days is easier than its ever been. In the
days before prehung doors, it took more tools and knowledge to
hang a door than it does now.
Imagine getting a door slab, an unassembled door jamb, hinges
and door hardware and having to do all the mortising, drilling,
rabbeting on site.
No longer do you need an array of tools such as a drill, a
mortising jig for hinges, strikes, and bolt plate. No jig for
drilling the backset for the doorknob and bolt.
Nowadays all you need is a hammer and hard trim nails or a
finish nail gun and some shims.
The first thing you need to do is check the opening you'll be
hanging the door in for the correct size. It should be 2" bigger
than the door size. Even though it's a rough opening it should
be reasonably plumb and square.
If the opening was framed by someone else, you may want to break
out your level and framing square and check this also.
Drywallers sometimes believe the rough opening was meant for
them and will let the drywall run into the opening. If this is
the case use a drywall saw or sawzall to cut it back.
Once all the vitals have been checked your ready to hang a door.
Prehung doors come assembled a couple different ways. They can
be bought with trim already mitered and nailed on to one side
and without trim. If there is no trim installed, I like to put
it on before I put the door in the opening. The trim is
installed on the hinge side.
Most doors open into a room and against a wall. When putting the
door into the opening, try to put the door in the center of the
opening. The door jamb should be able to move to the left and
right in the opening. The gap between the door and jamb on the
hinge side is usually about an 1/8" of an inch. This dictates
the gap or space you should have all around the door. Move the
door jamb to the left or right until you have that same space at
the top. You then nail the trim on the top hinge side and the
bottom hinge side. Then nail the strike side on the top making
sure you still have an equal space. Nail off the rest of the
hinge side with 3 or 4 more nails. The 2 nails already in the
top are all I usually put in. Now nail the rest of the strike
side starting at the top and working your way down, maintaining
the same space as the top and hinge side.
Once the door is nailed into the opening on the inside, it's
time to shim the door jamb. First, pull the door closed to make
sure it hits the door stop evenly on the strike side. If it is
hitting only at the top pull the hinge side toward you till it
hits even. If it hits only at the bottom, push the hinge side
jamb away from you till it hits evenly.
Once you get the jamb aligned put shims between the jamb and
stud opening, being careful not to bow the jamb into the
opening. If need be use a straight edge to keep it straight. I
put shims behind every hinge and the strike and also at the top
and bottom of the strike side. I nail these shims in with two
nails, one on each side of the stop.
The next step is to apply the door casing to the outside of the
door. Once this is done, your ready for the door hardware. If
everything went right, the bolt should engage the strike plate
and the door should fit snuggly against the stops.
(c) 2005 Mike Merisko www.sawkerfs.com
About the author:
About Author :
: Mike Merisko has been a carpenter for 26
years. Most of those years were spent in the homebuilding and
remodeling industries. He was also in business as a carpentry
and general contractor. While that is his forte, he also has
experience in bridge building, commercial construction, and
exhibit building which is how he earns his living these days.
You can browse through articles by him and others at his website
www.sawkerfs.com
