Lines sometimes look as if they meet but don’t quite because they are in fact off plane. This sill ensure that all lanes are planar.

One other way of dealing with the closing issue is to start with a rectangle bigger than you need and then to draw your lines on that, making sure that ends meet up. Floor plans can either be done with top views of your group in parallel view, or by creating horizontal sections. Then use scenes to show relevant views (ground floor plan, first floor plan, etc). At the very least, you would have Floors, Walls, and Annotations (text/dimensions), but you could break it down further into floors, say. I would create layers to represent different elements. Global settings parameter allowing user to toggle between standard stud sizes and custom sizes - Beam Tool (add to the columns module, one additional icon for toolbar). That makes it easier to see that walls run through from floor to floor where they are meant to. Some additional debugging or checking with the draw wall tool as it relates to auto-corner configuration and defaults for inputs. You can do the same with the next floor but instead of having it displaced horizontally as you have it, move it on top of your ground floor walls. If you want to show a floor, make that a separate group (could be just a simple slab of given depth). When you re-open the group, you will be able to extrude the walls to the height you want. Once you have the walls right, make them a group or component. You may have to keep deleting surfaces created that might usually represent the floor.

When I do this kind of thing (which is a lot), I start with the walls and make sure they all join up and create a surface between their real-world faces. You can work like that but you will soon run into difficulty. Lines, surfaces, text, dimensions, are all jumbled in together. I notice that everything is on Layer 0 and you don’t seem to have any components or groups. Looks to me like you may have gaps in your lines preventing areas from “closing”.

Draw 2d stud wall sketchup 17