Check a house footprint against a rectangular plot and your setbacks before planning rooms. Setbacks are your own figures; local rules are not looked up.
Example: a 20 × 30 m plot with 6 m front, 8 m rear and 1.5 m side setbacks has a 17 × 16 m (272 m²) buildable area. A 16 × 11 m house fits, covers 29% of the 600 m² plot and, placed at the front setback, leaves a 13 m rear garden.
Plan a house on a plot in GoSpace
Formulas
Buildable width = plot width − 2 × side setback. Buildable depth = plot depth − front − rear setback. The footprint fits when its width ≤ buildable width and its depth ≤ buildable depth; area alone is not the test. Site coverage = footprint area ÷ plot area. Placed at the front setback, rear garden depth = plot depth − front setback − house depth.
Next steps
Read Will a house fit my plot? for the worked example, then use the plot planner to place the house, driveway and gardens.