In Level 2 BIM products are described by 3-D geometry and by their accompanying technical information. The output from separate modelling systems, eg. architectural, building services, structural engineering are combined in a single common data environment to create a digital 3-D representation of the building and its systems. Using this model software can then enable the coordination of the mechanical and electrical services, for example, with the other building components such as the structure.
The same common data set, will allow an operative to select an object, such as a chiller, and interrogate its properties, such as when replacement parts are needed under planned maintenance. When collections of objects are joined to create a system, all of the objects in a system can inherit and share attributes, so potentially this would provide the planned maintenance schedule for a particular system, such as a chilled water system, for example, based on the collection of its components’ needs. It is the richness of the data that will determine the potential effectiveness of BIM as a maintenance tool.
Until now, very few building services product manufacturers have produced BIM models that incorporate data. Or, where data is available, it is often produced in response to a consultant’s questions on a bespoke basis and not in a standard format. Now that is about to change with the CIBSE and NGBailey launch of the BIMHawk website.
BIMHawk is a free online toolkit and suite of software programmes developed specifically to speed up the development, dissemination and adoption of standardised product data. CIBSE recognised the need for standardised product data back in 2011, when it was apparent that manufacturers were working in isolation to create their own, bespoke product libraries, often in response to demands from customers for data for use in a BIM model.
|A lack of consistency between manufacturers'|
data has held BIM back
CIBSE set out to establish a set of common parameters for different building services products through its creation of Product Data Templates. A PDT is a collection of parameters that describe a particular product, or product type. Only parameters useful to a designer, contractor or maintainer are included on a CIBSE PDT. To ascertain which parameters should be included on a particular PDT the Institution worked with trade associations, competing manufacturers, designers and facilities managers.
To date, PDTs produced by CIBSE include those for cooling coils, fan convector units and cable tray systems. For the full, up-to-date list go to www.bimhawk.co.uk. To allow manufacturers to create, complete and upload PDTs online CIBSE teamed up with Paul Marsland, design and BIM development manager of NG Bailey. The BIMHawk website is the outcome of this partnership. The website also allows PDTs to be integrated into BIM authoring systems.
One particularly useful feature of BIMHawk for product manufacturers is that for every parameter added, BIMHawk will check for that parameter in the BuildingSMART Data Dictionary to see if the parameter name already exists. BuildingSMART is an international organisation set up to enable BIM models to be exchanged from one platform to another through the use of a platform neutral language called Industry Foundation Classes. To do this each individual object parameter must be created with a common globally unique identifier, or GUID. If a parameter with the same name has been defined previously, BIMHawk will extract its GUID. If not, BIMHawk will generate its own definition and associated GUID.
When a manufacturer populates a PDT with product specific data to digitally define a particular product it is called a Product Data Sheet (PDS). Manufacturers can upload their product data sheets to BIMHawk. This will enable consultants, contractors and commissioning engineers to access standardised data and to compare products from a variety of manufacturers on a like-for-like basis to make specification quicker and easier. In effect, BIMHawk becomes a catalogue of catalogues.
|BIMHawk will soon contain data useful to other sectors, such as water|
Alongside the website, CIBSE and Marsland have developed a Revit plug-in to allow BIM models to acquire product data in a structured format from a PDT. The plug-in removes the need for manufacturers to create new product models from scratch.What’s more: the next iteration of the Revit plug-in will bring the values from the PDS into the BIM model. This will allow designers to look through the data sheets of different manufacturers to see which products are the best fit for a particular design concept and then import the data on the size and performance characteristics of that product.
With the launch of BIMHawk, CIBSE will help to speed up the development, dissemination and adoption of standardised product data. This will be a massive step forward in enabling collaborative working and the exchange of data and information throughout a project’s lifecycle in a consistent manner, something that until now has been missing.