[rascul]

> Pro-tip: most fasteners (nails and screws) are not "structural"; they hold wood in place, but they don't support weight. That's why eg windows are framed the way they are, instead of just nailing a 2x4 between two others; it allows each piece of wood to be supported directly by another.

Very good tip. So very often I see decks (for example) built improperly, relying on non structural fasteners to hold it all together. This kind of stuff tends to fail in a number of years. I've seen a few collapsed porch roofs for the same reasons. Make sure your fasteners are rated for how they're used. A general rule of thumb is that wood sits on wood, not attached to the side.