The bar has been raised by those who create "Super Families" that are not only high quality graphics without sacrificing modeling speed, but contain appropriate data and family nesting to allow for high powered scheduling and maintenance study and analysis. In my humble opinion, without appropriate descriptions, proper attributed data and takeoff abilities of a BIM product model, it's about as useful as socks on a rooster... while entertaining to watch, actually makes more work for everyone.
When looking for a content provider or creating your own, there are several things to consider. Below is what I believe to be the bare minimum tht should be contained within a BIM Object.
- Lipstick on a pig... Graphics need to be accurate and consistent with the intent of the model without slowing down the model's performance. If you put a $5,000 paint job on a Yugo, it still will only do 55, and if Kwik-Lube tunes your Ferrari.... well, you see where I'm going here. This delecate balance needs to be managed properly. Fixtures and fittings tend to be very graphic in nature with a lot of complex curves and angles. This level of detail detail can slow down the model if not done with some care.
- Size matters... Dimensions need to be accurate enough to consider tolerances and clash detection. Most electrical devices are created considering only the visual aspect and (Hopefully) the MEP connector, BUT, an electrical device has a box embedded in a wall thats about 2"x3"x4". Adding a simple solid behind a wall plate will allow that device to be considered a clash when a 3" DWV runs right over it inside of a wall.
- NO IMPORTS!!! - And no, I'm not talking about outsourcing graphics to Asia or South America... Imported CAD files converted into BIM files are large, slow and cannot be modified. Sizes cannot be modified, and proper rendering of these files is not for the novice or impatient.
- It's not you, it's me... Data needs to consider not only those persons placing the information in the model, but those using the model later. In addition to baseline information about the identity of a product, performance aspects are used for energy and structural analysis; product lifespan is used for future budgeting and sustainablility analysis.
- Fill in the blanks... This is an enormous pet peeve of mine that I see all the time. The description parameter is used for callouts. Materials or objects that have no description or one thet's too long or too short have a worthless callout. This is really irritating to the user when they need to go back and add this during the detailing phase.
- Tell 'em what they've won, Link - Links to useful information like code compliance, specs, product data, installation procedures and sales and marketing can really simplify the research aspect of product selection, by creating a singular point of reference to search from. NOTE - If the manufacturer cannot ensure that URLs won't change, data MUST be linked through a library that will.
- More than a simplified processes... Nesting families allows more than resueable components like door slabs and window sashes. It allows for option selection and more accurate scheduling and data management, especially for the FM folks.
- What are my options?... Nesting families allows multiple components of the same type to be selected as options. Doors may have hundreds of slab (or leaf) styles, but all of them come in the same sizes. The slab becomes a "Nested" component that can be "Swapped Out" by the click of a dropdown.
- Mother always told me to share... Shared nested families allow scheduling to be made more accurate and allow for mainenance components to be their own entity with their own attributes. Lets take a light fixture... The Housing of a Recessed light is a durable product with a lifespan of 20 years. the ballast and bulb are 2 components that are both components that will not only require replacement, but have options to select from. Nesting the ballast and bulb within the light fixture allows the ballast and bulb to have independant lifespans and installation dates for every light fixture installed. The FM team can see when every bulb and ballast was installed, and when they'll need to consider replacements.
- No do-overs... This one's a no brainer, but I always find myself needing to say it... If I can't modify dimensions without going into the graphics, there is something wrong. Appropriate dimensions need to be made parametric so when updates need to be made, it's not back at the drawing board.
- More than dimensions and materials... can be parametric. Equations can allow results based on other attributes. Calculations that determine if and where in the country a window meets ENERGYSTAR are created based solely on the input of a U-Factor and Solar Heat Gain.
I hope this has been an informative post and can give some insight as to what you should expect... no, demand... from your content provider. Content is being treated as something like BIMs read-headed stepchild, but the bar is raising on the level of detail required in the model. The needs of the architect are beginning to demand that content developers step up to the plate and take their BIM content seriously. The main difference between man and other mammals is the opposable thumb, and most of us choose to use it. The difference between CAD and BIM is the data... Let's use it... Don't settle for less, and don't just be conTENT with CONtent.