So I was slightly editing Varg's Tavern in Moonlight Falls (was adding in a Professional bar instead of the personal bars on the lower level.) And I noticed the roof has a bit of a pop-up, almost like a deck, or stage or Foundation, and then it has a roof over it. I was wondering how they built that? I have a Dive Bar I built that was based on a Caboose and want a similar roof pop.

I only have Late Night, Pets, Supernatural, and Seasons (And the base game.) Was this a build mode feature added with say WA/Ambitions or one of the other pre-Supernatural EPs I don't have?

It's a Frieze, added in a patch that came with Ambitions. Requires a cheat to use, here's a guide: http://au.ign.com/wikis/the-sims-3/Friezes

Excellent thank you!