There are a couple of ways to do this. Do what ever is easiest and understandable first. First go to image>3D window settings and in the effects turn on vectorial 3D hatching. With this on, a material that has a 3D hatch will show in the 3D window.
You can make two walls siting on top of each other, upper wall one material the lower wall a material that has a tile 3D hatch.
or
Make your wall, select the wall click on extras>accessories>wall accessories, find an object called moldings and panels. In here, change the geometry to suit you need and change the material with something that has a 3D tile hatch, click ok. Check what you have in 3D.
There are other ways to do it. These are just example of what you can do. Try different ways of showing what you to find what is easiest and fastest for you. Hope this was helpful