If you ever needed to edit the structure of the wall, look no further, I can help you with that. In the picture below you can see two types of walls. The former is so called full brick wall, which has both the inner and outer leaf made of bricks, with a cavity filled with insulation, the latter has outer leaf made of bricks and inner leaf made of concrete, again insulation is placed between inner and outer leaf.
When we want to make our own type of the wall. We can simply select an existing wall and at the properties browser choose edit type.
As a next step, I would suggest duplicate, in order not to overwrite the existing type. When you choose duplicate, you will be asked to name your new wall. You can address this in different ways (I might eventually cover this in posts to come) but always try to be persistent and logical in naming.
In the type properties, click on Edit structure.
Here you can see different layers which make the whole wall. I opened the former type of the wall. Here you can see the layers as I listed them above. So you are now able to change the material/thickness/order or assign a function to them.
On the picture above, you can see the new type of wall I made from the old one. This one consist of inner and outer leaf made of concrete, with 125 mm insulation filled cavity. Now just confirm with OK and you can play with your new wall.