Installing a pre-hung exterior door

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One of the first home improvement projects I tackled was replacing the storm door on the garage with a new pre-hung steel door.   I had never hung a door before, but fortunately I had some help from my friend, Dave.  I don’t know if he had ever hung a door either, but together we got the job done.

The garage was block and stucco construction with a wood frame around the doorway opening.  I wanted as wide a door as possible, which led to removing the existing wood frame.  The storm door was 82 inches high. My replacement door was the standard 80 inches so I had to deal with some extra space at the top.

With Dave’s help, I removed the screen door and the existing wood frame.  The frame was impaled on large nails  that were actually embedded in the block (interesting).  I used a reciprocating saw with a metal blade to cut the nails flush to the block.

New framing

For the rough framing, we used pressure-treated deck boards (one for each side and three to fill the gap at the top). That meant we could use wood screws to attach the new door frame.  We cut the top-most board to the width of the doorway (less a quarter inch to allow for adjustment).  Next, we cut the second and third boards shorter by the thickness of the two sides, basically creating a rabbet.  We screwed the top three boards together and attached the side pieces with screws driven through the top board.

The block wall of the garage is 8 inches deep.  Our door frame assembly was about 5 inches deep.  We set the frame back from the edge of the outside wall by an inch and a half. That way, I could use a 2×2 piece of lumber for trim.  We used concrete screws (Tapcons), to attach the boards to the block: 5 inch screws for the top (which was about 3 inches thick) and 2 inch screws for the 1 inch thick boards at the sides.

Installing the new door

With the easy part out of the way, we were ready to install the new door.  I found it to be an extremely frustrating undertaking.  It is possible to hang a door without a helper, but most do-it-yourselfers will find that a little assistance is required.  Word of advice:  shake hands and apologize in advance for all the swearing that you are about to do.  A little patience and a sense of humor go a long way.

We positioned the door in the opening.  The rough opening has to be about 2″ wider and higher than the door to allow room for adjustment.  In order to operate properly, the door frame has to be square and plumb.

Square:  The frame must be square so the door will close properly and securely, maintaining a good seal with the weatherstripping.  The door should swing smoothly and remain in the open position.

Plumb:  Vertical front to back and side to side. Check by using a plumb bob or a level.

We actually got very lucky. The hinge side of the rough opening was perfectly vertical so we didn’t need any shims for that side. It was then simply a matter of shimming around the rest of the door frame and screwing it to the rough frame. I then used expansion foam to fill the gaps.

I have been told that the proper technique is to shim the corners so they are square.  Then there is some debate whether it is better to shim and screw the hinge side or the latch side first.  Frankly, I have since installed several other doors and I don’t think I installed any two the same way.  The key is to continually check the swing and fit of the door and make any adjustments as you go.

Adding some trim

I used 2×2 and 2×4 lumber to bring the frame out flush to the exterior of the garage. For the transition between the door frame and this new trim, I used quarter round moldings.  Inside, I was a little less fussy, using 1×1 nailing strips for the trim.

As a precaution against water damage, we left a gap between the ground and the bottom of the frame.  This gap was filled with expansion foam and caulk. All joints and gaps in the trim were also sealed with paint-able caulk to prevent water penetration.

I painted the door and the frame to match the colors of the stucco and trim on the garage. The finished product, if I do say so myself, looks pretty good, though I wish I had used a semi-gloss finish (instead of satin) for the door.

Bonus tip:

Any dents and dings in a metal door can be easily repaired using auto body filler.  Sand the damaged area down to the bare metal.  Apply the filler according to the instructions.  Sand smooth, prime and paint.

Project completed summer of 1998.