Uniclass tool

1 Introduction

2 Classification tables

3 Tables for the layer generator and request tool

 

1 INTRODUCTION

 

Currently the classification system is based on a number of high level classifications.

1.1 General

 Uniclass is for use in organising many different forms of information including documents in libraries, project information, cost information, specifications, etc. Many potential users of Uniclass are at present users of CI/SfB and/or CAWS (Common Arrangement of Work Sections for building works). Uniclass includes all the topics covered by these two schemes, and in addition it presents some new tables and parts of tables, notably Table L Construction products, and a new project lifecycle classification (part of Table C Management).

Uniclass comprises 15 tables, each of which represents a different broad facet of construction information. Each table can be used as a “stand alone” table for the classification of a particular type of information, but, in addition, terms from different tables can be combined to classify complex subjects (see section on signs, below).

Many of the tables are inter-related in the sense that the same or similar words can appear in more than one table. For example “windows” appears in the Construction products table, in the Elements for buildings table and in the Work sections for buildings table.

The difference is that in the:

• Construction products table - windows are off-the-shelf products
• Elements table - windows are parts of buildings
• Work sections table it is the process of installing windows and its result which are classified.

Alongside is a full list of tables in Uniclass, with a brief description of their important features. Definitions of the terms used and examples are given in the introductions to each of the tables.

1.2 Technical description

1.2.1 Notation

Uniclass notation consists of a single capital letter followed by one or more digits, except for the Work sections tables (Table J and Table K) which have two initial capital letters so as to incorporate the CAWS and CESMM3 codes. To allow easy shortening of the notation the numbers are not padded out with trailing zeros to create a fixed number of digits. This causes no problems for computerised sorting systems, but sometimes confuses people who may intuitively think that, for example, D11 files after D2 (see 2.3 Filing order, below).

The Uniclass notation is hierarchical; for example D21, D22, D23, etc. are always subclasses of D2. This means that if, for your purposes, you do not require the full detail of the Uniclass tables you can delete digits and classify at a higher level in the hierarchy. This allows Uniclass to be used in many different situations, with differing degrees of detail.
 

2 Classification Tables

2.1 Suggested method for expansion and use of codes

2.1.1 Classifying the construction works – (original form)

In the Uniclass system different scales/complexities of construction works are recognised. In order of decreasing scale/complexity these are: construction complexes, construction entities, spaces, elements.

In many cases it will not be necessary to distinguish between construction complexes and construction entities; for example, both office complex and office building may be classified at D32. However, if it is necessary to make this distinction of scale, then the appropriate class number from Table E Construction entities may be combined using a colon with the D32, thus: D32:E0 Office complex; D32:E8 Office building.

Similarly, if it is necessary to indicate that the construction object in question is a space rather than a complex or a building, the class number from the facilities table may be combined using a colon with the class number from the Spaces table – for example: D32:F Office space; D32:F2 Office room.

However, colons should only be used as indicated above when absolutely necessary. It is not necessary to use combined class numbers when:

1. user activity is of prime importance in your collection and the distinction between construction complexes, entities and spaces is of little importance;
2. entries in the Facilities table themselves imply a particular size/complexity. For example D412 District general hospitals – these are nearly always construction complexes and certainly are never spaces in another building. Therefore in this case it is sufficient to use the class number D412; using D412:E0 would amount to tautology.

2.2 Guidance on the new form of classification and requests for additional classification for BIM

This capability is available on the website tools as follows.

The double, or even triple, coding introduces a level of complexity that is unacceptable for the generation and collation of Building Information Models (BIM), including infrastructure projects. The granulation required by the generators of CAD/BIM data would follow the need to break the building into systems and construction elements:

Example of Construction Elements

• Concrete Beams
• Concrete Columns
• Concrete Slabs
• Concrete Staircases

This may need to be further defined for granulation purposes as:

This creates a problem of selection of the code; G gives the element, P will give the material description. If applied as described in the code we would get:

Core Fabric: Foundations: Reinforced Concrete
G21: G311: P227

Which does not allow for a full description for other elements such as Beam, Column, Slab or Staircase?
 

Example: Taking core fabric as a catch all we can reduce this to:

Element	Code	Sub code	Sub sub code
Foundations	G21
		1 Pads
			1 Insitu concrete
			2 Precast concrete
			3 Reinforced concrete
		2 Pile caps
			1 Insitu concrete
			2 Reinforced concrete

 

e.g G2113 would be Foundation_Pad Reinforced_Concrete as a single code using the underscore as a deliminator.

Example: The structure could be defined under G26 Frame/isolated structural members as follows:

Element	Code	Sub code	Sub sub code	Sub sub sub code
Frames	G26
		1 Beams
			1 Steel
				1 Rolled
				2 Fabricated
			2 Concrete
				1 Insitu
				2 Precast
				3 Reinforced
		2 Columns/ stanchions
			1 Steel
			2 Concrete
				1 Insitu
				2 Precast
				3 Reinforced

Other items such as the Stairs would come under G23 and Floors under G22.

In this way the high level three digit code is maintained and granulation can occur in a structured way. If required this can be redefined on extraction from the CAD/BIM model files in spreadsheets and word documents.

For steel or timber construction the staircase should be seen as a single element:

Steel Staircase

Not a collection of construction elements:

• Stringers
• Treads
• Risers

3 TABLES FOR THE LAYER GENERATOR AND REQUEST TOOL

The tables being made available are to allow the industry to help develop the classifications for CAD/BIM use and to retain the current capability to link the classifications to Specification and Cost.

The original table can be selected or the current update based on extensive work on the Crossrail Project.

The tables G and H have been combined and re-titled as Construction Elements to eliminate the imposed distinction between building and infrastructure (civil) projects. In a BIM world there should be no distinction between the two.