Go to 3d view, right click the wall you want to be an interior wall, select the surface, properties... in the context menu (you'll see the surface selected highlighted by a red border to confirm you're looking at the right one), note the location/geometry information (I use alt-prtscn and paste into paint or an email.
Close the window, right-click one of the interior walls under the same space in your component tree, create new interior wall, copy one of the existing interior walls.
Alter the location/geometry to match the exterior wall's. Change to adiabatic if it isn't already.
[Alternative to adiabatic - it's just one more step to actually tie your shells together. Choose a "next to" space as the adjacent space in your second shell while defining your new interior wall's location/geometry. Now you're modeling heat transfer between the shells!] Close this window.
If you are tying the spaces together thermally per alternative above, delete both exterior wall sections and you're done. If you really want to create two adiabatic walls instead (more work), don't delete the second before getting its' geometry/location info, then repeat the above procedure.
Go to 3d view, right click the wall you want to be an interior wall, select the surface, properties... in the context menu (you'll see the surface selected highlighted by a red border to confirm you're looking at the right one), note the location/geometry information (I use alt-prtscn and paste into paint or an email.
Close the window, right-click one of the interior walls under the same space in your component tree, create new interior wall, copy one of the existing interior walls.
Alter the location/geometry to match the exterior wall's. Change to adiabatic if it isn't already.
[Alternative to adiabatic - it's just one more step to actually tie your shells together. Choose a "next to" space as the adjacent space in your second shell while defining your new interior wall's location/geometry. Now you're modeling heat transfer between the shells!] Close this window.
If you are tying the spaces together thermally per alternative above, delete both exterior wall sections and you're done. If you really want to create two adiabatic walls instead (more work), don't delete the second before getting its' geometry/location info, then repeat the above procedure.
NICK CATON, E.I.T.