I recently had a sliding glass door installed by a professional retail outlet. This was nothing special about this door, handle or latch.

After the install, the door would not lock. Several techs visited to repair the latch. Finally, they told me that the latch needs to be engaged with the door open, and lifting the latch half-way. I have to close the door with my hand on the latch to keep it up half-way, and when the door is closed, I can engage the latch the entire way. There is no way to lock the door with the latch when the door is closed.

Looking at the latch, it appears that when lifting the latch handle, it does not give ample force to the latch that would force it up into the lock. Some mechanism prevents the latch from engaging completely into the door frame, so even the slightest pressure prevents it from working. This is why the latch-lock must be half-way up with the door open to guide it into the hole in the door frame, and then when the door is closed, the lock will properly engage

Is this normal? It seems very strange.

 

Welcome to the Forums!

It sounds like it just needs adjusting. Can you tell us the brand and model of the door?

It may be that the latch mechanism needs to be turned 180...esp if this is a reversible direction door.

The latches on sliding doors normally reach out then pull back, shouldn't need any forcing.

 

I agree with Gunguy, its sounds like a door height adjustment issue.
By your description of the problem, it sounds like the latch bolt is not clearing the lower opening in the lock plate.
You can easily check that by transferring a small pencil mark,inline with the bottom of the lock plate opening, to the face of the jamb. Then bring the door within 1/4" of the mark and begin to engage the lock. When the lock sweep begins coming out of the door, you should be able to tell if it is high enough to clear the bottom of the opening.
It seems strange that you would have been left in that situation, rather than the techs simply adjusting the door though.

 

Thanks for the reply. This may be a reversable door, but I don't think the latch is upside down. The hook that comes out of the latch points up. The problem is, as the latch is pushed down, the hook starts to lift, but if there is any resistance on the hook, some internal mechanism does not apply any pressure to the hook to force it up, unless the hook is half-way engaged before there is any resistance.

So starting with the latch up and pushing it down, the hook hits the door jam, and does not engage to complete the lock, it hits a slight amount of resistance and the hook never comes out of the latch.

However, if the hook is halfway out, it will forcibly engage the door jam and lock.

The installer is adamant that this is the way the door is designed. I am skeptical.

 

If the latch height is not adjustable, the rollers of the door certainly are. Bring the door about 1/4" from being closed, and observe how the sliding panel lines up with the jamb. If it is straight, then both rollers need to be adjusted exactly the same amount... such as turning both rollers adjustment screws 1 turn upward, to raise the door.

If the gap is extremely crooked, this could be one reason the door isn't latching. The rollers could be out of adjustment. There is also sometimes a fine threaded flat head screw that adjusts the reach of the latch. There is surely something you can do to make this latch work the way it is supposed to.

You might also open the door slightly, and look at how the sliding panel meets up with the fixed panel in the middle of the door. Such as sliding the door open about 3", until the left rail on the sliding panel passes past the right rail on the fixed panel, and the edges of both pieces of glass start to line up. If this gap is straight, the door is probably installed level, plumb and square. but if it is crooked, then something is wacked out. This can cause problems with roller adjustment and latch alignment.

I suppose it's also possible that something got screwed up when the latch was installed. Sometimes if mounting screws that hold the handle are screwed too tightly it will pinch the door (esp vinyl) and then latches won't work right.

 

What the others said about adjusting the door is very valid.

The reason I asked about brand...

There is a specific latch mechanism used on many lower/mid-range doors that if a certain spring breaks (which it does quite often, even new) will exhibit symptoms similar to what you describe.

Does it exhibit the same problem if you use just your finger to apply pressure to the latch with the door open?

You can mention brand and retailer (if a national chain)..it will help narrow it down. Help us help you....

 

Rereading the post above:

The problem is, as the latch is pushed down, the hook starts to lift, but if there is any resistance on the hook, some internal mechanism does not apply any pressure to the hook to force it up, unless the hook is half-way engaged before there is any resistance.


Also, in addition to the others suggestions, this may be a cam issue inside the latch. There would be a pin that rolls through a doglegged slot on the cam.
If the pin is binding at the bottom of the slot from horizontal pressure (binds as pressure is applied via the latch handle) this would cause the symptoms described. Then once the pin clears the elbow through the slot, it works as normal.

If so, it may be a loose screw, needs some grease, or last resort lightly file the opening.

Regardless, I find it hard to swallow that this is a design feature.