What would be the process for drawing zoning setback lines for a property parcel polygon? I'm looking for a software agnostic solution - just a walk through of the general steps with enough detail that it could be done on a whiteboard.
In the U.S., zoning regulations typically define a property line setback for structures. For example, a building must be 20' from the front property line, 15' from the rear property line, and 10' from the property line. If I know which side of the property is the front, how would I draw the setback lines? In the image below, this would be bolded dotted line labled buildable area.
Things get more complicated for irregular shaped lots. How could the setback lines be draw for the lot as shown below?
Ideal the solution would work for any polygon that has 3 or more sides, provided the front property line, and optionally the rear property line is known.
Over the years, I have tried two different ideas without success.
The first idea would be to take the property polygon, and "shift" it in parallel with each of the property lines the distance of the setback. The resulting shape where all the shifted polygons intersect(overlap) is the "buildable" area of which the boundary is the setback lines. This works for rectanglar lots, but starts to fail when acute angles are involved. Plus you have to know which line gets which setback.
The second idea has to do with calculating the angles between each of the sides. But I've never been able to figure out what the rules should be for determing what is a side property line and which is the rear.
أكثر...
In the U.S., zoning regulations typically define a property line setback for structures. For example, a building must be 20' from the front property line, 15' from the rear property line, and 10' from the property line. If I know which side of the property is the front, how would I draw the setback lines? In the image below, this would be bolded dotted line labled buildable area.

Things get more complicated for irregular shaped lots. How could the setback lines be draw for the lot as shown below?

Ideal the solution would work for any polygon that has 3 or more sides, provided the front property line, and optionally the rear property line is known.
Over the years, I have tried two different ideas without success.
The first idea would be to take the property polygon, and "shift" it in parallel with each of the property lines the distance of the setback. The resulting shape where all the shifted polygons intersect(overlap) is the "buildable" area of which the boundary is the setback lines. This works for rectanglar lots, but starts to fail when acute angles are involved. Plus you have to know which line gets which setback.
The second idea has to do with calculating the angles between each of the sides. But I've never been able to figure out what the rules should be for determing what is a side property line and which is the rear.
أكثر...