Estimates done from the design are pretty common, and BIM programs (Building Information Management) like Revit integrate all of the construction details into the design model, so they are able to automate some of those calculations. But BIM programs are not great design tools (not sure if that's an inherent conflict or if there simply aren't any good ones) so they are not popular for smaller jobs like single-family homes where you can use drawings produced directly from a tool that provides a better user experience for design.

Unfortunately, the drawings don't give you any assurance that the construction details are done correctly. Corner-cutting aside, a contractor may depart from the design with good intentions and accidentally create a thermal bridge that sucks heat in or out of your house.