Advanced Glazing Calc's in Revit

[mibzim]

Australia has just recently brought out a "section J" of the building code which requires specific calcs to be done on all glazed areas of a building. They have provided a simple spreadsheet for us to plug data into, but i would love to do it all in revit.

So far, i can't see an easy way of doing it. Some info we need to plug in - such as reflectivity, height of shading above sill, etc - but i'm trying to get it to do a schedule of each glazed area with its surface area that i can then get it to perform further calculations on.

Problem is, we have glazing in curtain walls, doors and windows. Do i have to do a separate schedule for each of these, and then how am i meant to figure out which area of the curtain wall it is talking about? The material take-offs for area all seem to be wrong anyway - they report different areas for exactly the same family type!!

I tried placing filled regions over the glazed sections, but i cant schedule filled regions or their areas.

What do i do? Manual Calcs in an excel file?

[truevis]

I'd think you'd be able to do it with schedules, too. However if the material takeoff feature doesn't work right, that's a big problem. Try posting a small sample of what you've tried.

Worse come to worse, perhaps ACAD and tables would help. You can make a table of pline areas, IIRC.

[jtobin.68416]

In the past, I've added an instance Project Parameter called ORIENTATION, and assigned the parameter to exterior Walls, Windows and Doors.

I select all windows, etc. in the exterior and assign them "SOUTH", "NORTH", etc. Then sort by the parameter. I filter the wall parameter for curtainwall types. I get a unit area (though not a glazing area) from the windows by creating a calculated value of width x height.

It's not perfect for doors by any means, but all I get there is a unit count, and then add the glazed area.

Also, I have to create 3 different schedules but it's certainly better than the Excel AutoCAD routine.

Hope that helps.

John Tobin

[trombe]

Australia has just recently brought out a "section J" of the building code which requires specific calcs to be done on all glazed areas of a building. They have provided a simple spreadsheet for us to plug data into, but i would love to do it all in revit.

Hi,
I really think this is a (good) question for your software vendor.
This is part of what subs are about - helping solve real issues which affect the output or helping improve future output. They might have some valuable input , or this might prompt a service request for the factory.
I would not be surprised to see NZ head down a similar path with cals such as this sooner or later.
regards
trombe

[gordolake]

Hi, indeed the answer is to add project parameters, - orientation, shading width etc. to all windows and glass door families. ( I have found it essential for simplicity to change the glass door families category to windows so there is only one schedules to deal with.) This is a bit laborious but well worth the effort.

You can of course calculate the glazed area in the schedules directly by adding a calculated formula based on (height -frame width) X (width-frame width). Then use sorting, grouping and filters in the schedule to list the windows by level, orientation, and shading width and total the areas for common orientation and shading width.

I have not yet looked at section J specifically but in N.S.W. we have the state government's BASIX requirements http://www.basix.nsw.gov.au/basix.jsp for thermal comfort to deal with which need these figures to plug into their web site calculator for a certificate to be generated for the approval process.

Regards
Steve

[mibzim]

Thanks guys.... schedules work fine for plain old window families and i had started to set that up....

But when it comes to curtain glazing its another story. Orientation, area, width etc are not so easy to generate directly from revit. Also, i end up with two schedules that i then need to somehow filter by orienttaion and combine into one. Not sure how to overcome that one - begins to sound easier in the excel file provided with the BCA...

[gordolake]

Yes curtain walls, hmm good question ??? looks like seperate schedules, and the good ole adding machine.

[robert.manna]

I'd think you'd be able to do it with schedules, too. However if the material takeoff feature doesn't work right, that's a big problem. Try posting a small sample of what you've tried.

Worse come to worse, perhaps ACAD and tables would help. You can make a table of pline areas, IIRC.
There was a thread about this awhile back, turns out that Revit caculates all surfaces and adds them together, so in the case of a rectangular curtain panel there are six sides for which is calcuates material area and adds together. However, the area calculation of curtain wall panels should help, you merely need to filter and differeniate out your different panel types for the calculations that you need to do. I think this is very doable, it is just a matter of narrowing down what you need so that you can do the calcs. It may be that you will need more three schedules, you may need a schedule for each instance of curtain wall. Since Revit 9 allows you to save off schedules and re-import them, it should be fairly easy to develop some standard schedules with your calcs, that you then apply to your project and modify the filtering/sorting to get what you need. The use of the API to code a custom tool to help with this effort may be worth investigating as well.

-R

[david.kingham]

As far as calculating the area....Add a new material in your families called Glazing, you can just duplicate Glass so they look the same, now use the Paint tool to apply the glazing material to only one face of the glass, do the same for your curtain walls also, just create a new curtain panel and swap them out. Now create a Multi category material schedule and filter by the material name Glazing :)

[dbaldacchino]

There was a thread about this awhile back, turns out that Revit caculates all surfaces and adds them together, so in the case of a rectangular curtain panel there are six sides for which is calcuates material area and adds together. -R
I don't think this applies anymore. I placed a curtainwall, created a Curtain Panel schedule and got a total area. This matched the same areas reported by a material take-off schedule for curtain panels for both "Material: Area" and "Area".

[robert.manna]

Thanks David, I've been out of the loop for awhile.... :)


-R

[dbaldacchino]

NP :) I had to verify....we don't schedule glazing (we show elevations of all windows/frames) and I've read this in the past. We'll be looking at doing take-offs in the near future and it would be quite bad if you get more than double your materials in these cases!

[JohnCAVogt]

Just an update for RAC 2009, and a clarification ... 2009 does correctly do a one-face area takeoff per material of a curtain panel system panel, but it is still true that 2009 does not do a correct one-face takeoff of materials on an extrusion in a user-made curtain panel family. To get an accurate one-face takeoff you still have to make the extrusion a known-do-not-schedule material and paint the desired takeoff material onto the face of the extrusion.

[harry.mattison]

As Robert Manna suggests, this task could be nicely automated using the Revit API. The new Family API in 2010 would allow you to examine families (such as doors and windows), check the Element.Category property for each element, find the parts of the window made of glass, and then compute the area of these pieces of glass.

In the project environment, the number of instances of each family can be counted and multiplied by the glass area in each family. Several classes such as CurtainCell, Panel, and Mullion would allow you to find the area of glass in curtain walls and curtain roofs.

Regards,
Harry Mattison
Senior Software Engineer, Revit API

[robert.manna]

As Robert Manna suggests, this task could be nicely automated using the Revit API. The new Family API in 2010 would allow you to examine families (such as doors and windows), check the Element.Category property for each element, find the parts of the window made of glass, and then compute the area of these pieces of glass.

In the project environment, the number of instances of each family can be counted and multiplied by the glass area in each family. Several classes such as CurtainCell, Panel, and Mullion would allow you to find the area of glass in curtain walls and curtain roofs.

Regards,
Harry Mattison
Senior Software Engineer, Revit API

Harry,

Not being a programmer, there are a few things I'm unclear about with regards to how your suggusted command would work.


You state that the command could look for geometry elements assigned a glass material, and the area would be calculated. How would the API command know what "area" to calculate? The simplest form (an extrusion) has two "areas" that one could calculate, how does a command determine which is correct? Do you design a threshold? But then, you have to garuntee that the threshold you've defined is always true. Alternatly, do you assume that the family author always created glass geometry in a certain way. what happens if they used some other tool for creating the "glass"?
API commands must always "run" to completion, they can't just be running in the background, or something like that. How would this proposed command work? Would you be in a project, run the command, and then the command, would open the families to run the family processes, before returning back to the project to complete? Would a family authore run the command while creating the family to generate the data? But then, if it is a parameteric family, how do you account for change?Just some key questions from my point of view. When I suggusted an API command I was thinking something that would leverage the Material Takeoff information to make it easier to do the neccessary calcuations, rather then having to build complex schedules with formulas. A command could be written to even allow people to adjust the equations, variables and givens in the calculations as needed, like a "config" file for your area/code requirement.

Thanks,
-R

[Wagurto]

Is there any API that would help us to collect all glass area by orientation on a building?
Engineers are expecting this simple piece of information from our advance BIM program but Ifind myself doing it manually so far.
Let me know if there is something available out there these days.
thanks

[iankids]

Is there any API that would help us to collect all glass area by orientation on a building?
Engineers are expecting this simple piece of information from our advance BIM program but Ifind myself doing it manually so far.
Let me know if there is something available out there these days.
thanks

I don't know of any improvements or current API's out there.

Guy, a clever programmer in NZ, created an API for Revit 2010, however, with the massive changes which have apparently taken place under the bonnet, no longer works in 2011.

Hopefully, someone will take up the challenge and produce a functioning tool.

If you want to check out what Guy had achieved in 2010 you can find the info on his blog.

http://redbolts.com/blog/post/2009/10/08/Doing-it-all-in-Families.aspx#continue

Cheers,


Ian