There are a number of ways to make room boundaries for your project. The method you select doesn't really matter, what matters is getting you from the Drawing Discovery phase of work into full electrical design production.
Drawing Discovery is what we term the making of room boundaries, floor boundaries, room IDs, and the placing of floor match blocks. Creation/mapping of other elements like ceiling plans and recognition of important project elements like copiers are also part of this phase of work.
Here's a quick summary of your room creation options & some comments on each, please review when you are starting a new project where you don't see a quick and easy path to getting your room boundaries created.
In descending order of quickest time to completion:
1. Use supplied room inner perimeters. This is your 'easy out', as the architect has created room inner space boundaries that you might be able to use as your room boundaries. If the architect designed the building in Revit, the 2D floor plan export to you can always include the space boundaries...you just may have to request it. When you get room inner space boundaries that are closed polylines, all you have to do is change the layer to the zDL_ROOM_BDRY layer. Best case, these supplied boundaries will all work great. Worst case, some of them might not be suitable for use as-is due to oddities in their creation. These will show their stripes as not allowing lighting and/or receptacle automated placement to do their job. The solution is simple: manually redraw the boundary and delete the offending one.
2. Automated Room Creation. When the architect supplied source is relatively 'clean' (i.e. drawn to a consistent layering standard with no or few gaps between intersections), a well-executed Drawing Mapping and Automated Room Creation should yield good results. There may be some unsuitable boundaries created or complex spaces where the automated results need to be deleted and manually redrawn. There's lots of information on how to use Drawing Mapping + Automated Room Creation in the training videos: http://www.draftlogic.com/cms_pages.php?id=152
3. AutoCAD BOUNDARY eligible spaces. Where an individual space is relatively clean, the AutoCAD BOUNDARY command may be the best way to create your space boundary. This can be used throughout a drawing that is just not clean enough for Automated Room Creation but still has good linework intersections (i.e. great wall/window/door intersections), which might be the case if the layering is atrocious. Refer to this forums item for more information: viewtopic.php?f=8&t=133
4. Manually draw room boundaries. Whether you opt to draw it using AutoCAD's PLINE tool or use the supplied Drawing Discovery > Draw Room Boundary tool on the Command tool palette or on the DL_Electrical menu, the work and net result is the same--you select each vertex of the polyline and press 'C' to close the polyline when you have placed the second last vertex. There's lots of information on how to use manually draw room boundaries in the training videos: http://www.draftlogic.com/cms_pages.php?id=152
Give us a call if you need help deciding which of these methods of creation room boundaries is the best for your project.