A storefront door that will not close all the way is rarely a mystery once you look at it in order. Four things usually decide whether a door closes and latches: the closer, the way the door hangs, the latch and strike, and anything physically in the way.
1. The closer is not doing its job
A closer that has lost fluid, has a loose arm or has drifted out of adjustment may not push the door the last few inches. Most hydraulic closers have a separate latch speed valve that controls the final part of the swing. If it is set too slow, or if the spring is too weak for the door, the door stops short of the latch. Oil on the body or arm is a sign the closer is failing.
2. The door has dropped
Heavy glass doors hang on pivots, hinges or a floor closer, and those wear. As the door drops at the latch edge, the lock or latch no longer lines up with its strike. A scuffed threshold, a rubbed corner or an uneven gap at the top are clues.
3. The latch and strike no longer meet
Even a healthy door will not latch if the strike has shifted or the latch is worn. If the door closes fully but does not stay, check whether the latch bolt reaches the strike opening and whether anything is bent or loose.
4. Something is in the way
Debris in the threshold, a damaged sweep, a loose weatherstrip or a floor mat can stop the door at the last moment. Wind pressure can also hold a door open against a weak closer, especially in the afternoon.
What to do next
- Check for oil on the closer and for loose arm connections.
- Look at the gaps around the door for unevenness.
- Watch where the latch meets the strike as the door closes.
- Clear the threshold and look at the sweep and weatherstripping.
If any of these show a problem, a technician can usually identify the worn part. Fixing only the symptom, for example turning up the closer on a door that has dropped, tends to be temporary.