My favorite days of construction school are when we take on real-world projects, such as this week’s outings to install front doors at two residential construction sites.

I admit, I assumed it would be simple to remove an old front door and replace it with a more contemporary style. But after seven hours of heavy lifting, I have a whole new understanding of why people don’t change doors as often as they change seasonal wreaths.

A few observations:

1. In the words of our instructor, a veteran door guy, “First thing you do is throw away the instructions.” We did. The instructions had nothing to do with real life.

2. Also, from our instructor: No matter where you buy doors, chances are they’re gonna be jacked up. They were. We spent a lot of our time dealing with flaws in the new doors.

3. When taking out the old door, try to keep it in one piece, in case there are problems with the new door and you have to replace the old one for security purposes until you can have the new door remedied. We succeeded, despite our ham-handed efforts with a sledge hammer.

And there were generic worksite lessons we rookies learned, such as:

1. Always bring your own drinking water, in case water in the house is not on.

2. Bring earplugs, in case you’re installing a door in the entrance hall where a crew is installing hardwood flooring.

3. Set the circular saw depth to no greater than the thickness of the wood. The reason for this becomes evident after a circular saw nicks your colleague’s finger during a door installation.

4. Watch your language. It’s one thing to talk workshop talk in the workshop, but it’s quite another to do it in someone else’s entrance hall. It’s a little embarrassing when the homeowner joins you in the middle of a hearty “That’s what she said…”

If things go well, installing a front door can be a good entry point to working in a community. In our experience, a woman approached the job site and asked if we also did windows. Our instructor gave her his contact information and said we’d be happy to take a look at her project a few houses down. Then he explained to our class, “That’s how it goes: You do one front door, you do good work, and you can lock down the whole neighborhood.”