'Error: Core should contain a non-membrane layer' when merging wall regions

[tomnewsom]

I'm trying to make this wall. It's a parapet wall that gets insulated all the way around the top to avoid cold bridging. I split the air gap and the concrete core, and then merge the adjacent insulation into the new regions. It won't let me finish though. Any clues? I presume this is something that's been done before, but searching didn't help me I'm afraid...

[Zoltan]

Create a Rectangular profile that is as tall as the insulation is wide and as wide as the wall layers that is will span. Then, use it to create a Wall Sweep that is offset so that it is buried in the top of the wall.

[tomnewsom]

Good call. I ended up including the insulation within the core and joining layers outside and inside the core. This method does leave a join line (between the core insulation and the non-core insulation) but works ok for me :)

I'll give your version a go if that line bugs me too much...