It's not 'dive bar' casual, but I have seen everything from jeans and polos to business suits and clubbing clothes.
I'd feel comfortable there in casual, casual elegance, or formal attire. There is nothing pretentious about the place, despite the excellent food & cocktails, knowledgeable staff, and somewhat more upscale prices. That said, on weekends you'll also see a good number of people dressed up.
Cub Room is Casual Elegance. Its really good food and drink without being pretentious. I love it!
Casual as you want
Casual. Chef Greg is probably in cargo shorts and converse. True fact.
Come as you are!
Saw someone there in shorts!
Casual we went in jeans
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