Quantity calculation for composite walls

[Anonymous]

Now iam working on quantity analysis in archicad,In my project i have used composite section like a strut wall,since strut wall is made of gypsum board on either side and empty gap in the centre,Iam able to get the component list and also know to customise the component list,but when i use to get the volume of this composite section,it considers the complete thickness of composite wall which i dont want,i want it to consider only the gypsum part only,is there is any way to get it.

[Anonymous]

Try using global variables found in the appendix of the Archicad Help file. Once you find a variable that corresponds to your calculation use the "custom" function of the componant listing. You need to come up with a formula that subtracts the thickness of the gypsum to get your center volume. Something like this (WALL_VOLUME)-(WALL_SURFACE_A*gypsum thickness)-(WALL_SURFACE_B*gypsum thickness). Put the thickness of your gypsum wall board in where I call for gypsum thikness. Keep in mind that all calculations are in meters if you need feet and inches multiply by 3.2808. Hope this helps.

Barry Halloran

[Anonymous]

I may have misread the previous question. The formula I gave you would calculate the center volume subtracting the gypsum wall. If you rearrange the same variables you should be able to calculate the volume of the gypsum only. (WALL_SURFACE_A*gypsumthickness)+(WALL_SURFACE_B*gypsumthickness) if these particular variables don't work try using WALL_GROSS_SURFACE_A or WALL_GROSS_SURFACE_B in place of the ones above. Although if you use the gross area I believe all openings in the wall will be ignored.

Barry

[Karl Ottenstein]

ashok_hj wrote:
Now iam working on quantity analysis in archicad,In my project i have used composite section like a strut wall,since strut wall is made of gypsum board on either side and empty gap in the centre,Iam able to get the component list and also know to customise the component list,but when i use to get the volume of this composite section,it considers the complete thickness of composite wall which i dont want,i want it to consider only the gypsum part only,is there is any way to get it.

Sorry that I was on vacation and couldn't reply sooner.

You need to write a custom property object that is linked to this type of wall. The code in that object's property script will examine the global variables that describe the host wall and compute the needed values for components, etc.

Read the code in existing (out of the box) property objects to see how this is done. Note! If you search online help for 'property object', the manual will tell you to just open an existing object from the Calculate menu. You cannot do this after 7.0 since the delivered objects are inside the library PLA. Instead, open by subtype as shown in this mini-tutorial:
http://archicad-talk.graphisoft.com/viewtopic.php?t=5949

Barry's idea is on the right track with using global variables and reviewing those available in the GDL referance manual, but I suggest that you do the following. If you have some constant, such as gyp board thickness, make it a parameter of the Property Object, so that it is easy to change in the GDL object editor. If you have skins of a composite to deal with (as you do), then use the GDL global information to extract the values as they are defined in the actual composite. I believe that the WALL_SKINS_PARAMS array can be referenced from a wall-associated property object's property script ... but don't have time at the moment (in a motel) to verify. Having your script code verify the skins and retrieve the settings from that array is the only way to make your take-off robust enough to catch errors in either the script or the composite definition itself.

HTH,
Karl

[MarinRacic]

Karl,

Does this mean I need to make property scripts for every type of composite I have defined? Calculation Guide manual wasn't very helpful as all the examples noted there I can do also through Interactive Schedule.

What I need is to calculate, for example, volume of structural concrete in an external composite wall as easy as possible. How can I do it?

Thanks in advance!

[Karl Ottenstein]

MarinRacic wrote:
Does this mean I need to make property scripts for every type of composite I have defined? Calculation Guide manual wasn't very helpful as all the examples noted there I can do also through Interactive Schedule.

What I need is to calculate, for example, volume of structural concrete in an external composite wall as easy as possible. How can I do it?

Hi Marin,

Yes, it is rather unbelievable, but you either have to have a separate property object for each composite type, or you have to have a 'super' object and very perfectly, consistently named fills for your composite skins.

For example: if you use %25 as a fill for some of your composite skins, meaning some times that it is gyp board and other times that it is stucco, then a super-general-purpose property script would have no way of knowing what to generate when it came across a skin with fill %25.

If you come up with unique fills for each material that will ever be in any composite, and program your script to respond to those fills, then in principal a super-general-purpose script could take care of every composite.

This would require a lot of fills ... such as (forgive me using US-imperial to a metric guy - but I don't know meaningful metric numbers): "2x6 frame at 16" oc with Rxx batt insulation and Simpson yyy holddowns at 4' oc and fire blocking at ..." which of course has way too many characters to be allowed as a standard fill. (Needless to say, building wrap, vapor barrier, etc would all have to be skins in this methodology.) To subsitute for these crazy long names, you could have Wall001344 and look up in a table what a Wall001344 skin is. Works, but not easy to use.

Something in between is probably best: a single property object that can handle a family of related composites, but unique property objects for unique walls. By a family, I mean say a 2x4 interior wall that has several composites representing it: one with gyp on both sides, one with gyp on one side only.

To look at a property object and its script, see:
http://archicad-talk.graphisoft.com/viewtopic.php?t=5949

The user manual: this has always stunk. The examples in there, as you say, can easily be done with I.S. They need examples for using property scripts. The manual doesn't even hint at the possibilities of the Calculate functionality.

All of this scripting is really the wrong way, though, IMHO. Richard Morrison pointed me to the way take-offs are handled in Chief Architect and it is much more intuitive. Each MATERIAL has take-off information associated with it, and so when you buid a composite wall there, you are building skins made of Materials (with self-knowledge, if you will), not "dumb" drafting fills as we do in ArchiCAD.

The net result, is that if you script how a brick wall take-off is computed, then if you use that brick wall as the outer skin of a brick, air, CMU or brick, concrete, or brick, air, frame wall (etc) ... you don't have to write a script for the composite as we do and figure out what each skin is ... thus computing bricks in every composite associated script, but rather just one time when you define bricks. Chief does not have the computation flexibility of ArchiCAD, but this concept has a lot to offer.

If you agree, add your vote to this wishlist item:
http://archicad-talk.graphisoft.com/viewtopic.php?p=34077#34077

Sorry if not very coherent... I get very passionate about the Calculation possibilities...

Best regards,
Karl

[Anonymous]

Karl wrote:
...I get very passionate about the Calculation possibilities...

When is this "passion" going to become a comprehensive, coherent book? I'll send you my $10 now!

[Anonymous]

Karl wrote:
... Each MATERIAL has take-off information associated with it, and so when you build a composite wall there, you are building skins made of Materials (with self-knowledge, if you will), not "dumb" drafting fills as we do in ArchiCAD.

The net result, is that if you script how a brick wall take-off is computed, then if you use that brick wall as the outer skin of a brick, air, CMU or brick, concrete, or brick, air, frame wall (etc) ... you don't have to write a script for the composite as we do and figure out what each skin is ... thus computing bricks in every composite associated script, but rather just one time when you define bricks. Chief does not have the computation flexibility of ArchiCAD, but this concept has a lot to offer.

If you agree, add your vote to this wishlist item:
http://archicad-talk.graphisoft.com/viewtopic.php?p=34077#34077

Karl

This is definitely the direction Graphisoft should take with the calculations. It doesn't make sense that I could have the graphic representation of a brick veneer wall but could have a composite script that actually calculates a wood siding wall. Very non-intuitive.