problem fitting walls to "rovescio"

[giorossi]

Bye to all,
I press that I am at first with revit and even if for your kindness you will not write it you will think "look at you that backwards!" because probably at solution is under my nose.

I am following on the website lynda.com the course "designing a house in revit architecture"
When I have to make the outer walls, I have the problem that I have in the following pictures.
on the edges the outer walls do not come in the correct way if not maintaining the double finish towards the inside. but the double finish must be outside.
I also checked in the wall composition but the settings are the default ones.

What am I wrong? thanks for the help

 

[Tristan]

try to remove the joint and reapply it