Revit API Data Extraction for Family Type Quantities

[Cerclos]

Background:

We are developing a plugin that links a Revit model to a life cycle environmental impact and cost model within eToolLCD (a cloud based LCA tool).  eToolLCD has a large building component "template" library which is also customisable.  After linking a model, users will be able to match Revit Family Types with eToolLCD templates and eToolLCD will calculate the life cycle impacts of the geometry within the Revit design.  The team working on this are not Revit experts and are pretty new to BIM.  

Question: 

What would be the recommended method of extracting the Family Type Quantities?  We have considered the below methods and identified some possible pro's and con's with each.  Now we are interested in testing our perceptions with the Revit API Forum community, please be honest with your feedback!  

Option 1:

Access the data directly from the Revit Data model via the Revit API.  
Advantages: Should be quite straight forward, easy to implement
Disadvantages: Possibly have issues with custom categories / families (?).  Cannot re-use the work for integrations with other software

Option 2:

Access the data indirectly from an IFC export.
Advantages: Could re-use the work for integrations with other software
Disadvantages: IFC appears pretty flexible in terms of what attributes are populated, so perhaps no guarantee this would work anyway. Much more difficult to implement would need to define and export the IFC via the API. Could run into issues with custom categories / families etc

Thanks in advance!

[jeremytammik]

I agree with your assessment of option 1: straight forward, easy to implement.

Imho, the disadvantages you mention are overwhelmed by much more serious limitations if you base your approach on IFC export.

In that area, however, I am no expert, and cannot say for sure how much information might get lost, corrupted or inaccessible, and what importance that might have for you and your customers.

[MarryTookMyCoffe]

i would give up with IFC(just to much mess, gbxml integration we made in 2 month, with IFC we still trying for now we have a floor, wall and almost roof ).

option 1 seems better if there is no much time(and there never is) plus is that you get data in way you what.
but before you decide install revit lookup to check how elemnts are made and what data you can get.

I'm not sure how complex your project will be and what kind of element you what take, so for now it is all i can tell you.

[Cerclos]

Thanks Jeremy, I appreciate your insights.  I had almost come to this answer myself whilst exploring both methods briefly in Revit the last few days, but wanted to ensure these early findings were somewhat tested with the community.  Thanks again.  

[Cerclos]

Thanks MarryTookMyCoffe, great insight regarding GBXML vs IFC.  The fact you're only 3 categories in after one month is scary.  My mind is all but made up now!  Would you say that, given the flexibility of IFC, there is actually not a lot of advantage anyway in adopting this data format due to each subsequent integration needing detailed customisation of IFC export template anyway?

[MarryTookMyCoffe]

you lost me on second part.
I look on ifc from user perspective(colleague is in the ifc project, I only check from time to time progres). In revit there is like 8 IFC types and not every one work for my co-worker(not sure why).
From time to time some one send us a IFC file to linked in to a revit. Revit not always is capable link it(I give up after a 30min).
So if they have so much problem with it, maybe it is not that good format, but to be fair they ****ed up gbxml too.