Best way of setting up Composite Structures...?

[Anonymous]

Here's a scenario:

The reference line is on the "outside" of a wall. Now if I want gypsum board on one side of the wall only, do you recommend that I:

a) Have 2 composite materials set up, "wall | stud+gb | 90+10" and "wall | gb+stud | 10+90", and then assign one or the other, depending on which side of the wall I want the board...

or

b) Have only 1 composite, "wall | stud+gb | 90+10", assign that to the wall, then flip the construction method so that the wall is flipped to the other side of the reference line...and then adjust the offset of the reference line to make everything sit back in it's original location.

Method A potentially doubles the number of composites required for asymetric composites, whereas method B is either a lot more work or, if I set up each "side" in Favourites, doubles the number of Favourites required.

Do you have any recommendations?

[Karl Frost]

For something like this we generally go with Option B - more work in terms of constructing the model but fewer composites to deal with. In my (limited) experience I also find the skins tend to join better with this approach. Also editing Composites is painful so the fewer you have to deal with the better.

[Anonymous]

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.

[Karl Frost]

Wow, Peter, I'm impressed that you would even go there :shock:
OK I have a lot of experience with AC generally (been on it for 10 years now, is there some sort of gold watch/mouse for that?) but not a great deal with Composites, and we generally don't use the quantities/scheduling tools - so mych to try, so little time....
So I don't know for sure about this but I suspect you are right in that the position of the ref line is important. So back to Option A then - all I can say about this is, as mentioned before, creating/editing Composites is a real chore if you have a lot of them.
(Weather's a bit better today at least, though prob not what the Black Caps want..)

[Anonymous]

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.

[Anonymous]

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! 😞).

[Anonymous]

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 .

[Anonymous]

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

[Anonymous]

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

[Rod Jurich]

lec1212 wrote:
Excuse my ignorance.
What's it mean: "I'm glad we use a QS!)."
lec

Quantity Surveyor