With Element Templates settings for "patterns" you easily eg. can hatch your sections in Dynamic Views.
Download this example as packaged project (just unzip the folder "workspace" in the zipfile where your ".../workspace" -folder resides and you will find a user HATCH and a project HATCH)
Open Element > Element Templates and set hatch and crosshatch (or any other pattern) then apply this element template to your elements or better to the levels you want to place those walls (e.g. exterior and interior)
Tip: If you put the element templates into a file e.g. called template.dgnlib (in the /dgnlib-folder) they will be available throughout your whole project!
Mark Penn's Blog - Automatic Hatching Pattern in Dynamic Views