In my experience, depending on the strain, by the time it has a few sets of leaves you can smell "skunk" if you put your nose up to the plant.

By the 3rd week or so, the smell will start getting stronger and seep out...if you don't take precautions to seal off doorjams or freshen the air, you'll notice the smell when you walk in the front door. High heat and fan wind will make the odor seem stronger.

That said, I'm growing two plants, supposedly of the same strain...one smells and the other just smells like an ordinary house plant...genetics, I guess.