Answer to "Are there free programs I can use to draw construction schematics?"Google's Sketch-Up tool is free to download and use. It's not the most intuitively built program but, you can create just about anything from simple drawings to C.A.D.-like blueprints in 3D! I will say that there is a learning curve to this program. You will spend a lot of time reading the Help section and some more time online in the FAQ section and tutorial. There are others. Just Google it! Good Luck!