Hi Karl (I notice you're in Wlgtn too - a good day to be inside, eh?)

My hesitation with option B is that flipping and offsetting the reference line may cause issues later, when it comes to calculations, because wouldn't the reference line actually be on the opposite side as to what it visually appears to be?. e.g. Say I place an exterior wall of say 90mm stud, and I want 10mm wallboard as an inside skin. I assign a suitable composite, but it appears on the "outside". So I flip the Construction Method, and offset the RL by 100mm, to get the wall sitting in the right place again, relative to the RL - and have the wallbd on the inside. Now if I did a calculation to detemine the area of exterior cladding needed - usually done by using the side of walls that the RL is on - despite its visual appearance, wouldn't the RL actually be on the interior side in this case, so the calculation would be incorrect?

I haven't learnt or used Calculations yet, so I haven't been able to test the theory. Hence the question.

BTW, my experience is pretty limited too - I'm just doing my first project with AC now.

Assuming you are talking about what we call "furring walls" (one sided gyp), I generally use a single type and flip the construction method and adjust the reference line (rarely) as needed. This should have no adverse effect on quantities.

IMHO when it comes to reference lines you are best to offset these to align with the 'core' (eg. stud). Benefits include:
-you can flip one wall type to suit locations (mentioned previously)
-when defining your composite (for eg) make pb a skin, then when you dimension you can dimension cores only (preferences in dim palette).
-If you use the new display option 'core only' you don't get weird results where the reference line hovers beside the wall!
-Sounds onerous but if you carefully set up your wall types you can (using eyedropper etc) then use these around the project to your hearts content.
-Word of warning - if your lining thicknesses change, you must edit ALL instances of that composite and adjust the offset accordingly, or you can get some weird results!

Now just to really make your head spin - if you use the << marvelous >> cadimage wall builder you will have another level of complexity to think about!!(Esp. if you want to take off quantities. I find there are so many issues with doing that, I'm glad we use a QS! 😞).

what about using
Design > Modify Wall > Reference line .

as you can actually shift the reference line from side to side without creating a new composite nor fliping the wall .

whatever wrote:
what about using
Design > Modify Wall > Reference line .

as you can actually shift the reference line from side to side without creating a new composite nor fliping the wall .

Brilliant! I never realised that that option was so different than just changing the construction method, so I had just never used it. Thanks

Excuse my ignorance.
What's it mean: "I'm glad we use a QS! Sad)."
lec