I recently sent a tweet commenting on how confused manufacturers are in regards to BIM, which got quite a response. So, let me explain why and what I believe the manufacturer s need to do.
Over the last five years, manufacturers have been sold the need to make BIM objects. They have been targeted very aggressively by several BIM Library businesses telling them that if they don’t have BIM objects then they will never win any work in the new BIM world.
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So the vast majority of manufacturers paid their money (often very large sums) to get their products made into a 3D virtual representation, and often in many different file formats such as Revit, ArchiCAD, IFC, with the associated product attribute data attached to the geometry (in that file format).
Most manufacturers thought they were now “BIM ready” or “BIM Level 2 ready”, which they certainly are not, and this is why.
The main point of a BIM object is so that an architect/designer can pick the manufacturer’s object and insert it into their design model. In principle that is great, however, the issues are:
- Many manufacturers have made objects that have very little in the way of a geometrical USP – who cares if the insulation is a Knauf 3D geometry or a Kingspan one? It is just a rectangle or line in a model that the CAD software can produce. Also, many architects do not want/need to put all product-specific objects, such as ironmongery, in a model. So these objects are pretty much pointless.
- Many contracts state you cannot select a specific manufacturer’s product and many architects do not wish to do it anyway, as they would rather just specify the performance requirements of the product/system. They then use a generic object from the CAD package such as Revit.
- The data required for every project is different and is set by the client in the Employer’s Information Requirement/Asset Information Requirement. No client ever states “I want a Revit object with all the Revit parameters that you can give me”. But that is what 90% of BIM objects are. The clients will need different data depending on the type of the project and usually ask for very specific data requirements and usually in COBie or IFC, which leads to point 4.
- The contractor must collect the purchased/installed product data, based on the client’s data requirements. As we all know, what gets specified is not often the same product as what is purchased and installed by the subcontractor as the contract usually states it is “X product or similar/approved”. Therefore, if the contractor relied on a BIM object in a model from the architect, then there is a very high chance they have got data about the wrong product. And as the object is often a Revit BIM Object it has fixed Revit parameters that are most definitely not the same properties that the client has been asked for. So, a contractor like Skanska has publicly stated that they do not want BIM objects from manufacturers, they just want their product data. This leads to need for Product Data Templates (PDT).
The manufacturers are now realising that by having BIM objects they are not “BIM ready” and certainly not “BIM Level 2 ready”. So, as architects, contractors and operators are asking for the manufacturer’s data, and not necessarily a BIM object (remember they can attribute the data to any geometry), the question is: what data and in what format should be shared?
The PDT is meant to be a standardised way that manufacturers’ product attributes can be made available in machine-readable format. Therefore, Skanska can select the data they need and attribute it to the objects in the model so that they have the correct manufacturers product with the attributes that the client has requested.
So here lies the next layer of confusion for the manufacturer. CIBSE developed a working group to make standardised PDTs. They used IFC properties and then got industry experts to agree on attributes that should be included in the PDT.
NBS also produced its own PDTs as part of its BIM toolkit and these two types of PDT were not the same. Meanwhile, in Norway coBuilder developed more than 700 PDTs based on IFC, but with the attributes that are included in the standards that the products are tested against to meet the Construction Product Regulations (CPR).
So, a manufacturer has now been told that their BIM object doesn’t cut it and that they need a PDT, however there are now 3 different types of PDT! Confused yet?
Over the past six months common sense has been prevailing, as the European Union has set up a Product Data Templates group as part of its CEN 442 BIM standards programme.
First you must use the attributes from the EU standards (hEN) and from IFC, then you add additional properties that aren’t covered in the EU standards from the country’s own standards e.g. in the UK it’s the British Standard. This should give you about 60% of the product properties you would ever want to share.
The remaining attributes should then be agreed on by the market. To make this happen in the UK the Construction Product Association has set up LEXiCON so that the PDTs made by coBuilder can be supplemented with additional attributes that a manufacturer wants to share, but is not covered in a standard or IFC. Via LEXiCON the manufacturer can suggest an attribute and then industry bodies and experts can agree (or not) to include it into the UKs official PDT.
We are now getting set PDTs so manufacturers will be able to share their data in standardised machine readable formats, so what about the geometry? Well the answer is this.
If I were a manufacturer I would make a geometry of my product (providing it is an object that a designer would use, over and above a generic one in Revit). I would only make the geometry/s to the level of detail that my clients want (ie not to geometrically rich, if it is not required).
Then I would use the PDT and fill in my product-specific properties to make a Product Data Sheet (a PDT that has been completed by a manufacturer). Then, using a tool like goBIM, I would make my available my geometries (3D objects), my data in the PDSs and my documents.
Now the architects, contractors and operators can select the data they need in the format they require it in, the geometry they need (if they need it at all) and the documents they require and can combine them all in the model.
The manufacturers are now realising that by having BIM objects they are not ‘BIM ready’ and certainly not ‘BIM Level 2 ready’. So, as architects, contractors and operators are asking for the manufacturer’s data, and not necessarily a BIM object, the question is: what data and in what format should be shared?
– Nick Tune, coBuilder
