After The B & E: Repairing A Split Door Jamb

By Bruce W. Maki, Editor

Start:

I got a call about fixing a door. The lady said she went jogging and locked herself out. It was October and all the windows were closed and locked. Her only recourse was to break in, so she chose the patio door in the family room. She told me a couple of good kicks did the trick.

This premium hinged patio door looked okay from the outside...

...but on the inside, the jamb was split away (red arrow). A friend of the homeowners made a temporary repair by replacing the striker plates and securing them with drywall screws.

The first thing I did was peel away the weatherstrip. Many doors like this have a gasket that is held in a groove in the door jamb.

I removed the door casing trim by carefully prying it away with a small pry bar and a putty knife.

The Trick Of The Trade: I used a circular saw to cut away the broken part of the jamb. A is the aluminum-clad door stop section of the jamb. B is the interior wood portion of the jamb. This is the part I removed. Cutting this jamb was tricky because the blade kept touching the metal exterior jamb. That  didn't damage the saw blade, but scraped the light brown finish off the jamb. This view is from the middle of the doorway.

Another view of the same procedure, looking down. The saw cannot cut all the way to the end, so the last few inches had to be cut by hand or broken away carefully.

I removed the wood jamb.

I used a chisel to clean up the broken wood that the circular saw could not reach.

I used a putty knife to stuff the fiberglass insulation back into the gap between the jamb and the framing.

I measured the width of the new piece of wood.

I used a circular saw to rip a piece of 1x6 to the desired width. This Makita saw has a rip fence (red arrow) that makes the saw almost as accurate as a table saw.

I cut the board to length with a miter saw.

I set the new board in place. Accurately cutting the length is important.

The new piece of wood was pushed into place.

Mind The Gap: The original gap between the door and the jamb must be retained.

I cut away some drywall so I could push some shims between the jamb and the framing.

With the drywall cut away, the new jamb could rest against the framing. But that made a huge gap at the top (space between red arrows).

While the gap at the bottom was reasonable. This gave me information about what shims to use.

I used a brad nailer to tack some shims to the framing.

I used an adjustable try-square to ensure that the new jamb was the proper distance back from the stop.

The gap looked good all around. I sometimes try sliding a putty knife all along the gap... if it sticks, it's too tight.

I nailed the new jamb in place with 2 inch finish nails.

I had to re-cut the latch and deadbolt striker plates.

I installed the striker plates with 3 inch deck screws. This will make it much more difficult to break in next time.

Then I caulked the joints with Alex Plus (siliconized acrylic latex caulk).

The door looked as good as new. It just needed to be stained, which the homeowners decided to do.

The final step was to install the door casing with a few finish nails.

The homeowners told me that they had received one repair estimate, to replace the entire door (which was a 6' wide hinged patio door) for over $1200. They seemed pleased that my repair only cost them three hours of my time plus one piece of wood.

Thoughts On Making Doors Sturdier:

Many locksets and deadbolts come packaged with tiny 3/4" long wood screws to attach the striker plates to the wood jamb. I look at that hardware as something of a joke. I routinely discard these puny screws and replace them with much longer deck screws, long enough to penetrate into the framing by at least one inch. Then if the door is kicked, the jamb could split and the long screws may keep the striker plate from moving very far. But from my experience, even long screws will still not prevent the jamb from splitting. 

Factors that may help prevent jamb splitting, thus improving home security:

• Installing wood shims directly behind the striker plates. This is especially helpful if strips of hardwood or plywood can be slipped between the jamb and the framing, and secured with screws or long finish nails. The more wood around the striker, the better.
• Using expanding foam insulation in the gap between the jambs and the framing. Foam can add a significant amount of friction between two pieces of wood, as it bonds quite well to wood surfaces.
• Attaching some sort of metal plate to the backside of the door jamb, in the area behind the striker plate. I have not done this, but it stands to reason that anything that beefs up the strength of the jamb should make the door more kick-resistant.

Of course, having to break down your own door can be prevented by simply leaving a spare key hidden in some non-obvious location. Under the door mat is way too obvious. Hanging from a nail beneath a porch or deck is better, preferably some spot that can only be seen by lying on the ground. Few thieves bother to slither around on their bellies, no matter how snake-like they may be.

Copyright © 2001, 2005  HammerZone.com

Written July 31, 2001
Revised January 6, 2005