How the Height of Floors Relate to the Height of the Terrain


Reference Number: KB-00938
Last Modified: July 3, 2017

The information in this article applies to:

Chief Architect Premier


QUESTION

How does the height of the terrain relate to the height of my floors?

ANSWER

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.

Chief Architect programs automatically raises the building pad off the terrain for you.  The amount that the building pad is raised depends on the type of foundation you have built in your plan:

  • No foundation - The distance between Default Floor Height of 0" and the terrain is equal to the depth of the default floor structure thickness for Floor 1.

  • Wall foundation with footings - The distance between the Default Floor Height of 0" and the terrain is equal to the depth of the default floor structure thickness for Floor 1, plus the default Sill Plate Height of the foundation, plus 6" (187 mm).

  • Monolithic slab foundation - The Default Floor Height of 0" is raised 8" (200  mm) above the terrain.

  • Pier and beam foundation - The distance between Default Floor Height of 0" and the terrain is equal to the depth of the default floor structure thickness for Floor 1, plus the default Sill Plate Height of the foundation, plus 6" (187 mm).

    Note: The distances described above may vary somewhat in older program versions.
    Also, to make sure the automatic terrain height is up to date with the foundation type, select Terrain> Build Terrain.


To specify a different distance between floor and terrain

  1. With the Select Objects  tool active select the Terrain Perimeter, then click the Open Object  edit button.


  2. On the General panel of the Terrain Specification dialog, uncheck the box beside Automatic,

    In earlier versions uncheck the box beside Auto Calculate Elevation


  3. In Chief Architect X7 and newer versions, type in the needed value in the Subfloor Height Above Terrain field and click OK to apply the change.

    In Chief Architect X6 and earlier, this field was called Pad Elevation.