If you’re interested in energy requirements or ratings for buildings around the world, here are a few sites that can give you specifics. Each link is to one section within a larger website; those parent websites are all worth a bit of further exploration as well.
Existing Policies, from BuildingRating.org – select a region and see policy briefs on energy rating laws for that part of the world
Building Energy Disclosure Laws: The WegoWise Guide – describes existing and pending building energy & water legislation in U.S. states and cities
Country Fact Sheets, from BuildUp – Pick an EU country and see a summary of its European Energy Performance of Buildings Directive (EPBD) implementation, national legislation, contact info, and other relevant resources.