Understanding How the Height of the Floor Relates to the Height of the Terrain

Reference Number: KB-00861
Last Modified: July 16, 2015

The information in this article applies to:

Home Designer Professional or Home Designer Architectural or Home Designer Suite or Home Designer Landscape & Deck


I've noticed that the rooms on Floor 1 of my plan have a floor height of 0", and that this is not the same height as the terrain, which is also set at 0". Why is that?


In the real world, floor platforms are nearly always built so that you step up into a building.  There are a number of reasons for this, but perhaps the most important is to prevent the structure's framing from coming into contact with the terrain.  Over time, exposure to moisture in the soil can damage or even ruin untreated lumber in a framed floor platform or wall.  For this reason, building codes in most areas require that floors be raised off the terrain.

Home Designer programs automatically raise the floor platform off the terrain for you.  The amount that the floor is raised depends on the type of foundation you have built in your plan:


  • No foundation - Terrain builds 12" below the Default Floor Height of 0".

  • Wall foundation with footings - Terrain builds 6" below the foundation stem wall tops, which is 18 1/8" below the Default Floor Height of 0".

  • Monolithic slab foundation - Terrain builds 8" below the Default Floor Height of 0".

  • Pier and beam foundation - Available in Home Designer Pro only, terrain builds 6" below the tops of the beams, which is 18 1/8" below the Default Floor Height of 0".



In Home Designer version 7 and newer programs, you can specify a different distance between floor and terrain.

To adjust the pad elevation

  1. Select the Terrain Perimeter, then click the Open Object edit button.

  2. On the General tab of the Terrain Specification dialog, remove the check from the box beside Auto Calculate Elevation

  3. The Elevation field becomes active so that you can type in the needed value, and click OK to apply the change.