In the video below we show provide a few options as to how you can go about solving two key issues of Subdivision Modeling where the lot pads are stepped by e.g. up to 1.0 ft between the pads, and along the back of the lots they meet a -2:1 or -3:1 sideslope embanknment.
The Problem
The challenge is that the design provides the pad shapes and the pad elevations, the sideslope for the embankment may have a 2:1 max slope but the stepped pads all meet the sideslope along a single line which has the steps in it. When you model from the top of slope (with the steps) to the toe of slope that has no steps in it, then the step elevation difference has to get "wedged out along the length of the sideslope creating a step in the sideslope that decreases from the step height at the top of the slope to 0 at the bottom of the slope. This is for sure not an acceptable solution - so we have to find an acceptable way to remove the step at the top of the slope.
There are really only 2 ways to achieve this
- Create a vertical wedge across the back of each lot that takes out the step and creates a smooth line for the top of slope - this approach in the model solves the slope issue while keeping the lots exactly the same size and shape, however the solution creates a vertical face at the top of the slope which has a height of the pad step height. In this approach you offset the back of lot line by e.g. 0.01 and then remove the VPIs of the High Lot corner where it meets the low lot.
The larger the offset you create the less vertical the face will be and the slope wedge will be taken out over that distance - so for example you can push the offset out 1.0’ for a 1.0’ step and have a 1:1 slope with the slope wedges being more pronounced in that 1’ offset
- Create a sloped wedge at the back of each lot by pushing back the high lot and pulling the low lot forward by half the slope length i.e. if you have a 1’ step then to create a 2:1 slope you need to push the high lot back 1’ and pull the low lot forward 1’ at the point where they come together so that a 2:1 slope from the back of the high lot will meet the low lot line at the 2’ offset. To do this you have to zig zag the push pull line (Blue) as shown in the diagram below - the benefit of this is that it minimizes the effect on each lot and keeps the lot size the same (you gain a wedge and lose a wedge on each lot) and you can maintain the max 2:1 slope requirement and have no slope wedges at all.
You can then add “smoothing lines” (green) to the top and toe of the wedge slope that you created.
Video shows you how to do this in a real world example.