Windows and Doors/Frozen door latch
QUESTION: In winter, moisture gets into the door latch mechanism and freezes. We can always open the door, then the plunger part of the latch freezes in open position. The door latch and deadbolt lock are separate, and we must use the deadbolt to keep the door closed.
The house is 3 years old, had has had this issue from day 1. I lived in my old home for 28 years, never had a door latch freeze.
It's obvious the moisture comes from inside the house, but with moving parts I can't figure how I can install a vapor barrier on the door handle.
How do I stop moisture from getting into the latch mechanism?
ANSWER: Is the temperature in the room that the door is in normally cooler than the rest of the rooms in the house? Say like a mud room, a door leading to the garage or a side entrance where there are 6 stairs leading to the basement and 5 or 6 stairs going up to the living space, like a typical city raised ranch house?
---------- FOLLOW-UP ----------
QUESTION: This is the front door of a bungalow.
The door to the garage always works fine, as does the man door of the garage. The garage is heated to 1.5C at all times; heated to room temperature a couple days a week.
You said the house is three years old. It is one of two things or even both combined.
When the door knob was installed, the latch may have been set on the floor by whoever installed it and got tiny bits of sawdust and or drywall dust on the slide part of the latch. Just enough for it to absorb moisture. This did happen to a builder I know and when he took the door knob off, he could actually see specs of sawdust, which attracted moisture like a sponge.
Or warm moist air from inside the house is getting into a small gap where the door knob and latch are. So somewhere there is a small gap between the door knob & door that you may not even be able to notice.
The first thing I would do is to take off the door knob and latch and clean it in mineral spirits. Put it all in a container with a lid and let it soak for a fifteen minutes. Then shake the contained for about ten second to get any dirty or particles out of the sliding parts of the latch. Dry it off real well. I use a hair dryer because it will take a while for the mineral spirits to dry if you just allow it to air dry. Of course do not do it anywhere near the container with the mineral spirits. Then take a product like WD 40 and make sure you spray all the parts on the latch & door knob. Thoroughly clean out the opening in the door before you put the door knob and latch back in.
If it was not dirty, then somewhere there is a small gap between the door knob & door that is allowing warm moist air from inside your house to get into the latch area. You may not even be able to notice the tiny space or gap. Take a little clear caulking and go slowly around the part where the door knob assembly meets the door. Do the same on the outside edges of the latch. Then wipe it the excess with a damp rag to smooth it out so you don't see it.
The do sell heat strip tape that are used to keep door knobs from freezing in severe cold weather in Canada and Alaska. But I have not seen them sold in stores in my area.