to create context for your project you can use the toposurface tool to add a site
because visibility is turned off for the topography category in a standard floor plan view, you would want to open a site plan view so that the toposurface will be visible once it is created
located on the 'massing and site' tab of the ribbon, the toposurface tool is modal meaning that when the tool is selected, the ribbon displays a contextual tab providing the tools you need to create and edit the toposurface
to exit this mode you must click either finished surface or cancel surface
you will create the toposurface by using the place point tool to place points in the site plan to represent spot elevations
the toposurface geometry is automatically generated using the points
a toposurface can also be created from imported CAD files that include 3D contour information or from a points file which can be generated by certain civil design applications
on the options bar for elevation enter 10 feet
a spot elevation of 10 feet will now be established at each location where you click to place a point
change the elevation value on the options bar and place additional points
as you place the points the toposurface is generated and contours are displayed
the sloping toposurface can be seen in a 3D view
to modify the toposurface and provide a place for the building model you can place a building pad in the model
the toposurface will react to the position of the pad element
to do this, click the building pad tool which is also modal like the toposurface tool
a closed loop sketch of the extents of the pad must be completed to generate the pad element
you can use the pick walls tool to pick walls already modeled in the project
use the 'view cube' to manipulate the view so all of the perimeter walls can be picked to create the sketch
to close the sketch loop, use the trim tool selecting the portions of the lines you wish to keep
when the sketch is completed, click the finish edit mode checkmark to complete the pad and exit sketch mode
to give the toposurface some depth, you can use the section box in the 3D view
to do this, click on an empty part of the drawing area to select the view and then on the properties palette, under extents, select the section box option
when you select the section box in the 3D view you can move the shape handles so that the edge of the section box intersects the edge of the toposurface on all sides
the top of the section box is adjusted up so that when the roof is placed on the model it will not be cut
with the section box still selected right-click and select the 'hide in view' option to make the edges of the session box not visible in the view
the material of the toposurface can be changed by selecting it and clicking the value for the materials parameter on the properties palette
in the materials dialog a grass material is then selected for the appearance
finally on the view control bar you can apply a shaded visual style to the view to get an idea of what the building will look like