How to Design Underground facilities such as carpark or house basement?

[ehsan_omidHTLEZ]

it is possible to develop building on surface plan. how about designing underground facilities such as basement or underground carpark?

[jay.polding · Accepted solution]

Have you found a way to draw below grade/underground? 

[jay.polding · Accepted solution]

Ok, I just found the way to do this. Draw a Zone around the area you want to 'dig' down. Use the Terrain edit tool to pick the Zone and set the negative elevation. Then draw your building based on that lowered topo.

[jay.polding]

One issue with this technique is that the line-buildings drawn above snap their base automatically to the lowered terrain. The basic buildings don't seem to do that.