Good question Stella,
The size of the "bottom part of the 'L'" will determine if you are just strengthened in that area, or if the house has a large "missing" section. If you have the Level Three course check out page 11.
If not, is that bottom part 1/3 of the width or 1/3 of the length of the home? If so, you make the rectangle and the empty spaces are "missing," and there are some things you can do in regards to activating them.
Much Love, Shawn