Adding building footprints to DEM

Discussion created by blair998 on May 1, 2011
Latest reply on May 2, 2011 by blair998

I am a student learning Arcmap 10. For our project, I need to add a building footprint raster layer (with heights set to 10 m) to a DEM of the South Island of New Zealand. I have managed this with the raster calculator, except that on the combined raster dataset areas outside of the footprint locations have a no data value, while point locations (the buildings) show the DEM height + 10 m (which is good).

I am wanting the output DEM to also have values (from the native DEM) where there are no buildings. I have seen something about IsNull and Setnull etc but I don't understand this, and am not seeking help from my tutors :) The goal is viewshed analysis. Any help with the syntax appreciated.