The chair analogy...I don't know.
When you first come to a chair you make an educated guess about the chair. It looks sturdy enough. Then you form a hypothesis based on the information provided. Then you test that hypothesis by sitting in the chair. You do this multiple times and you then have knowledge that the chair will hold you.
I don't find faith in any of this because faith is believing it will hold you without any attempt at testing it first. It's closing your eyes and saying, "I have the faith in my heart that this chair will hold me." then you sit and it either does or doesn't. Faith is confirmed or discounted by saying, "Well maybe I wasn't meant to sit in that chair and I have to wait for the chair that is for me." It doesn't matter if the chair was made out of paper.
Same with the doorknob. My experience with the doorknob says it will work, I use the same method above, however also knowing that doorknobs are mechanical and mechanical things break down I have to allow the chance that doorknobs break even if it takes 10,001openings to have things go awry.
But, I think you are mashing together both definitions of what faith means.
You have: 1. complete trust or confidence in someone or something and 2. strong belief in God or in the doctrines of a religion, based on spiritual apprehension rather than proof. (Source: Google)
So, in your examples, you can claim that is a faith-based act and be correct by use of that non-religious definition.
I agree with what you said regarding the Bible. That's how the story goes. And if things still occurred like that then there would be no room for debate. But the faith it takes to believe a 2000-year-old story with little to no good supporting evidence is hard for some of us. We also have come to know how much the Bible itself has been changed over the years, not always by a stroke of evilness or anything, but by scribes simply making transcribing errors. Then we have passages from the Bible found at different times through history and some of these things do not have the same stories or endings as more recent finds (eg. The story of the woman caught in adultery (John 8) is not in the Codex Sinaiticus.). So, the Bible has been changed by human hands and by human thought. Things have been added, subtracted, changed, changed again and on, and on, and on to where the Bible(s) we have now don't represent what was really written. Humans created the Bible, voted on which scroll made it in and did not make it in and you can argue that was done under divine authority.
I would have no trouble believing if it was done by any logical means. Does God not appreciate the brains he allowed us to have? By doing so, he must've have known that some would use that brain to question his very existence. And why shouldn't we? If this is the greatest question we can answer, why wouldn't he make it beyond question that everything is Christianity is true? Why have some been convinced and others not?
But, I know, all of these things do not matter to one who believes. Faith trumps everything or so it seems. God said it. I believe. And that's that! It doesn't matter if it is demonstrably false in faith's eyes.
I am ready to believe given enough good evidence. No faith, but knowledge. As I was leaving religion, it was a prayer I prayed often. To be shown in some way that it was all true and that I was mistaken, but I was never shown and eventually I got tired of praying to the ceiling.
"Do not believe in anything (simply) because you have heard it ; Do not believe in traditions, because they been handed down for many generations ; Do not believe in anything, because it is spoken and rumoured by many ; Do not believe in anything simply because it is found written in your religious books ; But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it." -2500 Buddha Jayanti (page 39)
And, no, I am not a Buddhist.

But this says only believe in the things that agree with reason after observation and analysis.
After so much thought on this, I've come to the conclusion that religious belief really stems from the fear of annihilation of the self. We cannot die because we are such awesome creatures that we have to be special and there has to be something after these 80 some years of consciousness. If not, then what's it all for?
So, yeah, I call myself an atheist, an agnostic atheist, but I don't totally discount there isn't "something" that got this all started or whatever; I don't presume to know that I know either, but I don't think it's any god or gods that the human mind has thought up because these gods are too much like us. They hate what we hate.
It is said that any alien civilization with technology above and beyond our own could be seen as gods. What if it's true that we are nothing more than an advanced alien's science fair project? How could you prove me wrong?