[2011] Revit Space Type Settings (OPEN)

[Bvogt]

It would be a huge benefit to the mechanical designers if we could Save As the space types to have space types that are not listed. The Space Types appear to be based on A90.1 Table 9.6.1 Lighting Power Densities. Mechnanical Designers use A62 Table 6-1 Ventilation Rates.

There are many variations that cannot be directly addressed with the existing space types. Example, Classroom people densities are different than Lecture Classrooms. Additionally there are many space types used that are not listed.

If we could modify spaces similar to Schedule Settings that would do it.

Thanks
Bob

[mjdanowski]

Someone (I think Kyle B) explained why they did this, though I can't remember the reason. I do remember that it was a reasonable argument though. Anyone remember that post?

[jason.martin]

Don't know about the post, but I know the reason :-)

The space types today are actually tied to the gbXML space type list (which originated with the ASHRAE list). gbXML export uses the space type (required parameter of the space) when we export. Creation of a custom space type would create a situation in which we would be producing invalid gbXML output, as there isn't a space type called "jason's office" in gbXML, which is the reason for not being able to create a new space type today.

Obviously a valid request to create new ones, and there are ways to solve the gbXML export problem, so feel free to chime in if you think this would help you.

hth

jason

[Bvogt]

Using the A90 lighting power densities to define space types was not a good idea for gbxml. The A62 space types have more of an impact on people densities and ventilation loads. I have a nice A62 schedule that performs all the calculations but to use it using the power of Revit it requires me to select some other space type that does not apply and revise the people densities to an A62 type space.

I suppose one could use the occupant or comment field in the space properties and manually add A62 space types for HVAC purposes. Perhaps a A62 field along with a selection table could be added in future releases.

I don't fully understand why gbxml would care what a space is called. I export to Trace and it is just a name in a field that brings in data.

Thanks
Bob

[pcunningham]

The inability to create custom spaces types is pretty low hanging fruit in the Revit Universe. The "it works this way because of gbXML" isn't a good excuse, since Revit evolves at much higher rate than the gbXML schema. Develop a system that works within the Revit vernacular, and solve the gbXML issue separately.

Jason I'm curious what you have in mind when you mention potential work around? I know one is to just take an unused space type and change it to suit your needs. Which is lame at best, confusing at worst. Then I have space schedule which always require the footnote "Prison Cell = Lab, Theater = Janitor's Closet". No good!

The reality is, the entire process from the moment you click on the "Heating and Cooling Loads" button is fraught with disappointment. I anxiously awaited to see this overhauled in 2011, and essentially NOTHING changed. All we got was the "Use Load Credits" checkbox and some alleged gbXML improvements under-the-hood.

Revit spaces need to handle the same sort of hierarchy that is already precedent in just about any heating/cooling software (Trace, HAP, EQuest), where spaces are made up of loads, airflow, and construction profiles. Load profiles are made up of occupancy, equipment and lighting. Airflow is made up of supply, exhaust, infiltration, ventilation, and transfer airflow profiles. Profiles are made up of schedules. Constructions are made up of layers, layers are made up of materials. All of these need to be individually managed and then combined to form whatever compilations we need.

Some of these are in place in Revit where it is essentially mimicking gbXML. However you can't control each of these individually. To make a single "construction type" that includes roofs, walls, windows, etc all in one definition is silly...as you need to make a separate construction type for every possible permutation of roof/wall/window that might occur on a building. These are assigned to spaces...and not the applicable surface. Again, this is wrong, as it makes it impossible to have more than two wall types in one room, or two window types in one surface, etc.

The entire "Heating and Cooling Load" pop up is such a vestigial appendage. A hodge-podge of programming bits and pieces that need to be totally overhauled to be of any use. It's so frustrating to see articles like the new "Solar Radiation Technology Preview". These are such impractical and flagrant gimmicky eye-candy. Don't get me wrong, it'd be awesome to use this tool. But please get the fundamentals of heating, cooling, and ventilation working first.

My 2 cents.