ASSEMBLY CODES & OMNICLASS NUMBER

WHAT ARE THEY?

Classification systems are standards that attempt to name and uniquely number everything in a building.

If a family is identified with its classification number that number can be used by others further down the production line. For example cost estimating, construction scheduling and facilities management.

It is common for clients or contractors to expect BIM models (i.e Revit projects) to contain classification data. If COBie is required classification data is mandatory.

There are two main english language classification systems:

OMNICLASS is from the USA.

UNICLASS is from the UK.

Both have been, or are being, updated. Some parts of OMNICLASS have a "2010" version, and there is a UNICLASS2 which will supersede UNICLASS.

OMNICLASS and Uniclass are both made up of a number of tables. Some of these tables are based on pre-existing classification systems.

So for example OMNICLASS has Table 21 - Elements, which is based on UNIFORMAT by CSI , "a method of arranging construction information based on functional elements, without regard to the materials and methods used to accomplish them. These elements are often referred to as systems or assemblies."

Whereas Table 23 - Products is not based on a pre-existing classification system.

Revit, being from the USA, has some parts of OMNICLASS built into it.

In theory it is possible to construct UNICLASS reference files to use in Revit, but none have officially been released. Also UNICLASS2 is incomplete so is impractical to use.

CLASSIFICATION IN REVIT

Revit provides two places for classification codes.

OMNICLASS NUMBER

Loadable families (i.e. families that can exist as a separate .rfa file) have an OMNICLASS parameter.

It is only accessible whilst editing a family, so can not be changed once a family is loaded in to a project.

It can be found under Family Category and Parameters:

The Omniclass Number parameter uses values from OMNICLASS Table 23 - Products.

Revit is helpful in that only omniclass numbers relevant to the family's category are offered, so if in a door family it only shows classification numbers relevant to doors.

Revit will automatically fill in the Omniclass Title value.

ASSEMBLY CODE (UNIFORMAT)

Codes from OmniClass Table 21 - Elements are called Assembly Codes in Revit, and just to be confusing are often referred to as Uniformat codes.

Unlike the OmniClass Number parameter the Assembly Code parameter can be changed once the family is loaded into a project.

The Assembly Code parameter can be found under the Identity Data grouping:

Again Revit will only offer codes relevant to the family's category. Although you can change that by selecting something different from the Show classifications for: drop down list.

Revit will automatically add the description to the Assembly Description parameter. There is another parameter - Assembly Name - which does not get filled in by Revit. Both of these parameters are only accessible once a family has been placed in a project.

Note that the Assembly Code parameter is a Type parameter - it applies to types, not individual instances.

For this reason keep the code value as high in the tree as you can.

CLASSIFICATION SETTINGS

OMNICLASS NUMBER

The OmniClass Number values comes from a configuration file called:

• OmniClassTaxonomy.txt

The location and name of the configuration file used for OmniClass Number can NOT be changed, so any updated file has to have the same name and be copied to the same location.

Location is (in 2015):

C:\Users\<current user name>\AppData\Roaming\Autodesk\REVIT\<product name and release>

Examples:

C:\Users\<DoeJ>\AppData\Roaming\Autodesk\REVIT\Autodesk Revit 2015

C:\Appdata\antony.mcphee\Application Data\Autodesk\Revit\Autodesk Revit 2016

To ensures that any new future users of this computer will get the updated file also copy file to:

C:\ProgramData\Autodesk\<product abbrevation>\UserDataCache

Example:

C:\ProgramData\Autodesk\RVT 2015\UserDataCache.

There are different versions but all have the same name. The original file is based on a 2006 draft version of Omniclass and is NOT correct.

The newest complies with OMNICLASS 2012. It can be identified by its file size of 308kb. This should be copied to the folders above.

The newest file does NOT have category sorting as described above.

Also the codes are not strictly OMNICLASS compliant. Revit has full stops between each number pair, OMNICLASS has a dash after the first pair and then blanks.

Revit: 23.10.05.10

OMNICLASS: 23-10 05 10

The OmniClassTaxonomy.txt file is a tab delimited format with the structure:

<OmniclassNumber> <OmniclassName> <DepthFromTop> <-RevitCategoryNumber>

e.g.

23.10.20.14.10.11 Slurry Wall Membranes 5 -2000011

(the most recent file has <-RevitCategoryNumber> missing)

ASSEMBLY CODE

The location and name of the configuration file used for Assembly Code can be changed.

However the path seems to be saved in each file, so you have to change the path or file every file.

There are 2 available Assembly Code configuration files:

• UniformatClassifications.txt

• UniformatClassifications_2010.txt

UniformatClassifications.txt is NOT correct. Use UniformatClassifications_2010.txt.