When sketching your floor plan, do not forget to calculate in the wall thicknesses. A basic rule of thumb is 4” for interior walls and 6” for exterior walls. Actual construction drawings will vary a little, but those numbers will keep you on track for now. Some of the Home designer's sketches that showed room interior measurements which totaled the overall width of the exterior of their home, this design problem is often ended up redesigning the floor plan because those rooms to be a certain size on the inside. So be very calculative while sketching the floor plan for your home design. www.larryshomedesigns.com