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buildingSMART UKI Sustainability Data for Design and Decision Tools for Low Impact Buildings.

This standard presents how IFC can be used to transmit sustainability data about whole buildings, systems, products and materials. It is the result of collbaorative discussions between some of the 14 TSB funded "Design and decision Tools for Low Impact Buildings".

Purpose

This document was proposed for the BS8544 working group in response to issue of establishing a common industry data structure and methods of reporting and analysis of energy/carbon. Several inputs are sought including:

· ISO standards, particularly 15978 and 15804
· BS standards
· standardisation work with the RICS/CIBSE/HVCA
· participants of the TSB ‘Design and decision tools for low-impact buildings’
· buildingSMART (International Alliance for Interoperability)

Background

In March 2010 the UK Government Technology Strategy Board (InnovateUK) awarded 14 contracts to consortia keen to develop applications focused on Design and Decision Tools for Low Impact Buildings. Conversations started in two (involving F+G, BRE, University of Bath, Autodesk, IES among others) and now involving others, with a view to creating an Interoperability Agreement. This will bring together use of IFC with an agreed set of terms for environmental impacts and functional measures for buildings and for products and materials. This agreement will overlap (in a positive way) with the proposed UK BSI B/555 work on product libraries, work in the USA by NIBS on product specification and work in France CSTB. It is likely to form input into the UK BSI work, and should gain endorsement from RICS, other committees in BSI, and hopefully other bodies. Its first success will be to make BRE and University of Bath ICE carbon data re-usable, hopefully in the autumn 2010.

Justification

To respond to the upcoming carbon agenda, the industry needs to listen to the demands made on it and to learn from the knowledge and experience that is accumulating. Owners, designers and specifiers, and suppliers can benefit from sharable, structured information. The imminent emergence of several tools for design and decision making for low impact buildings has focussed attention on the potential for interoperability between data providers and consumers, including support for libraries for comparisons and benchmarking.

Use cases

The critical tasks are analysis, comparisons and meeting objective benchmarks for auditing and targeting. Each of these tasks requires the critical consideration of the relevance of available information.

Comparisons may be applied at portfolio, building, system, component or material levels.

Objective

This document aims to support the re-use and comparison of low-impact data in the facilities sector. The business objective is to enable both commercial and informal sharing. The technical objective is to transmit both environmental indicators and functional measures attached to a well-described object, in preference to transmitting ‘rates’ without context. Holistic assessment requires that input data and output data be re-usable, at every level from portfolio down to material. This is achieved by making a single common format.

This is summarised in the overall objective:

“Sharable data should fully identify the object, its functional measures and its impacts at specific life cycle stages, in clearly identified units.”

Objects

Objects typically have a name and description and various other Attributes. Objects also have various kinds of Relationships to other objects. Objects may include portfolios, facilities, systems, components and materials. Objects can be transmitted as separate library resources or collected together into a composite model. .

Outcome

This document provides schedules of terms and examples of how an international data standard for the facilities sector can be applied.

Exclusions

This standard seeks to ensure that values are available within a context of a particular object and not in abstract. It is then for the user to decide if the values can be appropriately re-purposed.

The sending and receiving application may calculate and present any values and ratios. Presentation may be done using numeric, graphic or statistical presentations.

Individual applications may support sub-sets of range of objects, the lifecycle stages, and impact indicators. Their user interfaces and their internal data stores are not obliged to use the terms documented here, as long as there is a correct mapping to and from the file format.

Other industry sectors, such as process plant or infrastructure, may adopt the terminology documented here and then show how other data standards in use in those sectors can be shown to be interoperable with this standard.

Outline

In order to meet the objective, it is necessary to define the use of a common data standard, and the use of specific names within that standard. The use of a common data standard covers its “schema”, the abstract definition of the domain being represented, and its “format”, the representation of actual data in files. The agreement on the use of specific names for the UK context covers:

· Object types (such as portfolio, building, systems, components, materials).

· Attributes, including the functional measures such as “Gross Internal Floor Area”, and impact indicators such as “Climate Change”. The impact indicators will cover either snapshot of the impacts to date such as “Embodied”, or a time-based prediction of future impacts such as “Annual”.

· Classification systems, which can be applied to organise objects, such as “BCIS”, and to organise the life cycle stages such as “Production”.

Common file format.

A common file format should be independent of applications’ user interface and storage technology, compliant to existing international standards and implemented in existing applications and tools.

The international standard ISO 16379, known as IFC and in particular the current version IFC2x3 has the following features:

1. It has been developed over the last 15 years by a buildingSMART, (formally IAI – the International Alliance for Interoperability) a consensus organisation of coordinating national and regional chapters.

2. It has developed the IFC data schema to be a comprehensive representation of the products and process for the AECOO (architecture, engineering, construction, ownership, operation) sector.

3. It covers product, process, actors, and supplementary resources. It also covers attributes of the objects and the representation of the relationships between these objects.

4. It has a core object schema which can be supplemented by international and localised implementation agreements. The most important of these covers ‘property sets’ and ‘quantity sets’,

5. It endorses two file representations of models. The extension “.ifc” is used for IFC STEP (ISO 10303 part 21) also called STEP Physical file format, which is a concise format widely used for the transmittal of large models. “.ifcxml” is used for IFCXML (ISO 10303 part 28) which a full XML schema (XSD). Tools to read, validate and write XML are freely available in all programming languages and platforms. These two forms are completely inter-convertible.

6. IFC is supported by all the BIM vendors and many existing analysis packages. Clients, especially large and government clients, demand IFC in the USA, Finland, Norway, Denmark, Germany and elsewhere. For example the majority of federal clients in USA demand IFC deliverables from their design and handover processes.

The case for interoperable BIM and product data is discussed in two free UK publications published by BSI:

http://shop.bsigroup.com/Browse-by-Sector/Building--Construction/Building-Information-Modelling/

Information about buildingSMART and the public definition of IFC is available at:

http://www.buildingsmart.com/

http://www.iai-tech.org/

http://www.iai-tech.org/ifc/IFC2x3/TC1/html/index.htm

Common terms

Object types

The IFC standard can represent portfolios, facilities, systems, components and materials. These and many other objects are defined by their function or type. Examples include:

· Portfolio: IfcProject or IfcGroup which can represent a portfolio of sites and buildings.

· Facility: IfcSite and IfcBuilding. A site can contain many buildings. These can if necessary be broken down into sub-sites and sub-buildings.

· System: IfcSystem and IfcZone, IfcBuildingStorey, IfcSpace. Zones contain spaces, whereas the others contain Components. The “external envelope” can be considered as a system, and it can contain other systems such as “External walling”. Some specialist systems exist including for example IfcElectricalCircuit.

· Component: IfcBuildingElement and IfcBuildingElementType (with about 200 subtypes). The paring of “element” with “element type” helps distinguish between actual occurrences of products in a facility from their common catalogue product types. For example there are both IfcDoor and IfcDoorStyle including frame and leaf. A prefabricated pod or module can be considered as a Component, as a Component can contain other components.

· Material: IfcMaterial and IfcMaterialLayerSet. A material is homogenous, whereas a material layer set represents a layered construction.

Attributes.

Common.

Attributes are provided to represent the Name and Description of all objects. Most objects also have a reference to an owner (i.e. creator). This allows the creating person, organisation and application to be documented. Many other characteristics of the objects are already documented in the IFC standards.

Functional measures.

Functional measures can be associated to an object. These quantities are used to represent indicative, beneficial, physical characteristics. There are recommended names for functional measures from UK standards for portfolios and buildings. Systems and components will typically be characterised by their served area, or as discrete units. Constructions and materials are usually characterised at square metre and cubic metre level. An example from the UK context might be “Net Internal Area” which is defined by professional standards and is recommended for characterising several building types.

Table 1: Names for functional measures.

Based on RICS NRM Part 1 Appendix E. With additions for Materials, Components, Systems

· Measures

o Numeric

§ “Seats” / “Students” / “Places” / “Bed Spaces” (i.e. primary occupants)

§ “Vehicles” / “Animals”

§ “Bedrooms” / “Cells” / “Consulting Rooms” / “Court Rooms” / “Screens” (i.e. primary spaces)

§ “Units” (flats, buildings etc.)

§ “Pews”

o Linear

§ “Length”

o Area

§ “Net Internal Area” / “Gross Internal Floor Area”

§ “Projected Area” ( such as the area of a window, door, slab, roof or wall)

§ “Area Served” (for services, transport and circulation).

o Volumetric

§ “Volume”

§ “Packed volume” (where needed for transport analysis)

o Mass

§ “Mass”

§ “Packed mass” (where needed for transport analysis).

To represent functional measures, IFC2x3 provides the ability to associate ‘element quantities’ to an object.

Impact indicators

Indicators are the key to Design and Decision Tools for Low Impact Design. They may cover environmental, economic or social effects. By convention, impact indicators measure the un-beneficial effects.

Some indicators relate to an object considered historically, to date, such as ‘Embodied” CO2 equivalent whilst others relate to an object projected forward into a number of years into the future such as for “Operation”. Terms should be agreed for the name of these indicators, separately from any duration information.

Indicators may be fundamental measures or they may be composite, being derived by applying factors or weightings to more fundamental measures. These factors need not be transmitted as the formula may be implied by the name of the indicator. For example “BRE Ecopoints 20xx” refers to a formula adopted by BRE to weight thirteen other indicators.

Economic impact is essentially “Cost”. It may be useful to specialise costs between the owner and the occupier. Other specialisation, such as cost to society may be required.

There are few measurable indicators for social impact. They can be included here as and when they emerge. (see TC350 part 3). At the broadest level they may fall into “physical”, “mental” and “communal” dis-benefits, and may be measured in person-year-equivalents. They may cover disruption, noise, transport pollution and other loss of amenity.

Indicators, especially economic indicators, may need to carry the context of a specific date and a specific location.

Table 2: Names for environmental, economic and social indicators.

· Environmental

o “Total Primary Energy Consumption”

o “Water Consumption”

o “Hazardous Waste”

o “Non Hazardous Waste”

o “Climate Change”

o “Atmospheric Acidification”

o “Renewable Energy Consumption”

o “Non Renewable Energy Consumption”

o “Resource Depletion”

o “Inert Waste”

o “Radioactive Waste”

o “Stratospheric Ozone Layer Destruction”

o “Photochemical Ozone Formation”

o “Eutrophication”

o Carbon Dioxide

o “BRE Ecopoint 20xx”

· Economic

o “Cost”

§ “Internal Cost” (owner/landlord)

§ “External Cost” (tenant)

· Social (none proposed for implementation yet)

o Physical

o Mental

o Communal

“Climate Change” is synonymous with Carbon Dioxide Equivalent: The total weight of carbon emissions with other emissions converted to CO2 effect, produced by a product or material. It is expressed as mass of CO2 equivalent emissions.

To represent Impact indicators, IFC2x3 provides the ability to associate ‘property sets’ to an object. A property set can contain several properties so that an impact and its life-cycle stage and its duration can be modelled. Not every property need be defined.

Table 2a: buildingSMART recommended Environmental Impact terms and measures

Term	Measure	Formal definition
Total Primary Energy Consumption	Energy	Quantity of energy used as defined in ISO21930:2007.
Water Consumption	Volume	Quantity of water used.
Hazardous Waste	Mass	Quantity of hazardous waste generated.
Non Hazardous Waste	Mass	Quantity of non-hazardous waste generated.
Climate Change	Mass	Quantity of greenhouse gases emitted calculated in equivalent CO2.
Atmospheric Acidification	Mass	Quantity of gases responsible for the atmospheric acidification calculated in equivalent SO2.
Renewable Energy Consumption	Energy	Quantity of renewable energy used as defined in ISO21930:2007
Non Renewable Energy Consumption	Energy	Quantity of non-renewable energy used as defined in ISO21930:2007
Resource Depletion	Mass	Quantity of resources used calculated in equivalent antimony.
Inert Waste	Mass	Quantity of inert waste generated.
Radioactive Waste	Mass	Quantity of radioactive waste generated.
Stratospheric Ozone Layer Destruction	Mass	Quantity of gases destructing the stratospheric ozone layer calculated in equivalent CFC-R11.
Photochemical Ozone Formation	Mass	Quantity of gases creating the photochemical ozone calculated in equivalent ethylen.
Eutrophication	Mass	Quantity of eutrophicating compounds calculated in equivalent PO4.

Further candidate names

Climate change : kg CO2 eq (100 yr)
Stratospheric ozone depletion : kg CFC-11 eq
Eutrophication : kg phosphate (PO4) eq
Acidification : kg sulfur dioxide (SO2) eq
Photochemical ozone creation - (summer smog): kg ethene (C2H4) eq
Human toxicity : kg 1,4 dichlorobenzene (1,4-DB) eq
Ecotoxicity to water : kg 1,4 dichlorobenzene (1,4-DB)eq
Ecotoxicity to land : kg 1,4 dichlorobenzene (1,4-DB) eq
Fossil fuel depletion : tonnes of oil equivalent (toe)
Waste disposal : tonne solid waste
Water extraction : m3 water extracted
Mineral resource depletion : tonne of minerals extracted
Nuclear waste : mm3 high level waste

CEN TC350 currently requires the reporting of the following environmental indicators:

input of non renewable energy resources, primary energy
input of renewable energy resources, primary energy
Input of net fresh water
Input of renewable secondary fuels
Input of non-renewable secondary fuels
Input of secondary material
Global warming potential, GWP
depletion of the stratospheric ozone layer, ODP
acidification potential of land and water sources, AP
Eutrophication potential, EP
formation potential of tropospheric ozone photochemical oxidants, POCP
Abiotic depletion potential for fossil resources
Abiotic depletion potential for non fossil resources
hazardous waste to final disposal
non-hazardous waste to final disposal
Radioactive waste to final disposal
Components for re-use
Materials for recycling
Materials for energy recovery

Service life factors.

Service Life may be associated to an object, either as reference duration or as estimated duration. Factors may represent the modification of the reference duration in a particular context. IFC provides a property set for aspects of service life that can be attached to objects.

Notes

The service life affects the indicators of ‘replacement’ stage of life cycle.
Service Life factors include one that documents the relative intensity of maintenance which affects the indicators of the ‘maintenance’ stage of the lifecycle.

Component and material factors.

Factors may be associated to a material or component in general, or they may be associated to a specific instance: These can be added into IFC property sets.

Waste factor
Reclaimed for manufacture factor
Reclaimable after use factor
… Others (to follow)

Notes

The construction waste factor affects the indicators of the ‘installation’ stage of life cycle
The reclaimed and reclaimable factors affect the indicators of ‘re-use’ stage of life cycle.

Portfolio, building and system factors.

Factors may be associated to a building or system: These can be added into IFC property sets.

Location factor
Inflation factor

Notes

Location and inflation factors affect cost indicators at every stage of the life cycle

Classification systems

Object classifications

Object classifications are widely used by client, professional and supply organisations. These range from internal, ad-hoc classifications through to classification systems that have been endorsed at national and international levels. In order to support the widest facilities community, it may be necessary to support several such classifications. By taking an object-based view, any number of classifications can be associated to any object. However for comparability, it will be useful to agree the name of the system as well as the codes to be used. Facility and Design focussed classification systems are of primary interest. Work sections and Products classification systems may be of secondary interest.

Table 3: Names for classification systems. (Unverified – illustrative only)

· Facilities

o “Uniclass Table D 1997”

o “Uniclass Table E 1997”

· Design

o “CISfB 1977”

o “BCIS 19xx”

o “Uniclass Table G 1997”

o “Uniclass Table H 1997”

· Work sections

o “CAWS 19XX”

o “NBS 19XX”

o “Uniclass Table J 1997”

o “Uniclass Table K 1997”

· Products

o “Uniclass Table L 1997”

o “UNSPCC 19xx”

IFC2X3 allows objects to be associated to any number of classification systems. Each classification system can be identified by name. Version and publication details can also be given. The classification value includes a (code) name and description.

Life cycle stage classifications

Environmental, economic and social impact indicators may be classified to a specific stage of the life-cycle. Life cycle stages are hierarchical. Some indicators may be defined parametrically, for example impacts associated to “Transport” may need to be treated separately in order to adjust for known location of the factory and the facility.

Table 4: Names of life-cycle stages and their hierarchy. (Unverified – illustrative only)

· “Whole Life Cycle”, Cradle-to-Grave (time-based, distance-based)

o “Cradle-to-Site” Build (fixed)

§ “Production”, Cradle-to-Gate, 15978: Product stage

· “Growth” (for sustainable farming and forestry)

· “Acquisition” mining, extraction, 15978: A1 Raw material supply

· “Production Transport”, 15978:A2 Transport

· “Manufacture” processing, 15978: A3 Manufacturing

§ “Procurement”

· “Transport” (distance-based) distribution, 15978: A4 Transport

· “Installation” construction, assembly, 15978: A5 Construction Installation Process

o “Usage” (time-based) simultaneous. (see part 10) SMLCC ISO, 15978: B Use stage

§ “Occupancy”, ISO, 15978: B1 Use stage

§ “Maintenance”, 15978: B2 Maintenance

§ “Repair” Minor, 15978: B3 Repair

§ “Replacement”, 15978: B4 Replacement

§ “Refurbishment”, Renovation, 15978: B5 Refurbishment

§ “Operation”, 15978: B6 Operational Energy Use

· heating, 15978: B6.1 Operational energy use - heating

· cooling, 15978: B6.2 Operational energy use - cooling

· lighting, 15978: B6.5 Operational energy use - lighting

· ventilation, 15978: B6.3 Operational energy use - ventilation

· hot water, 15978: B6.4 Operational energy use – hot water

· electrical, 15978: B6.6 Operational energy use – automation control

§ “Water”, 15978: B7 Operational water use

o “Disposal” , End Of Interest/ End of Life, 15978: C End of life stage

§ “Deconstruction”, Re-use, 15978: C1 Deconstruction

§ “Disposal Transport””, Re-use, 15978: C2 Transport

§ “Recovery” 15978: C3 Waste processing for reuse, recovery and/or recycling

§ “Sent To Waste”, 15978: C4 Disposal

Cradle-to-gate: Indicators associated with the product life cycle based on the starting from mining (‘cradle’) and ending at the manufacturing factory gate (‘gate’). This includes mining, raw materials extraction, and processing.

Cradle-to-site: Indicators associated with the product life cycle based on starting from mining (‘cradle’) and ending at the construction site (‘site’). This includes mining, raw materials extraction, processing, manufacturing, distribution of the material to the construction site, construction and assembly on site.

Cradle-to-grave: Indicators associated with the product life cycle based on starting from mining (‘cradle’) and ending at the end-of-life disposal or recovery (‘grave’). This includes mining, raw materials extraction, processing, manufacturing, distribution of the material to the construction site, construction and assembly on site, usage, and disposal or recovery of the material after its useful life.

Table 4a: buildingSMART recommended names for life-cycle stages.

Stages

Production

Transportation

Installation

Usage

Disposal

Whole Life Cycle

User Defined

Not Defined

This list can be expanded by offering this agreement and recommendations made to the buildingSMART Model Support Group.

Units

Metric Units

Metric (SI) units are fully pre-defined in the IFC schema, along with their seven ‘dimensional exponents’.

Other Units

Other units can be defined with factors to convert to the appropriate metric unit. Hence it may not be strictly necessary to agree names for these units. For reference the following are suggested, others can be added.

Table 5: Names of new non-metric units.

· Time

o “year”

· Energy

o “kWhr”,

o “MWhr”

o “therm”

· Power

o …

IFC recommended names for non-SI units

*Name*	*Description*
'inch'	Length measure equal to 25.4 mm
'foot'	Length measure equal to 304.8 mm
'yard'	Length measure equal to 914 mm
'mile'	Length measure equal to 1609 m
'square inch'	Area measure equal to 0.0006452 square meters
'square foot'	Area measure equal to 0.09290 square meters
'square yard'	Area measure equal to 0.83612736 square meters
'acre'	Area measure equal to 4046.86 square meters
'square mile'	Area measure equal to 2 588 881 square meters
'cubic inch'	Volume measure equal to 0.00001639 cubic meters
'cubic foot'	Volume measure equal to 0.02832 cubic meters
'cubic yard'	Volume measure equal to 0.7636 cubic meters
'litre'	Volume measure equal to 0.001 cubic meters
'fluid ounce UK'	Volume measure equal to 0.0000284130625 cubic meters
'fluid ounce US'	Volume measure equal to 0.00002957353 cubic meters
'pint UK'	Volume measure equal to 0.000568 cubic meters
'pint US'	Volume measure equal to 0.000473 cubic meters
'gallon UK'	Volume measure equal to 0.004546 cubic meters
'gallon US'	Volume measure equal to 0.003785 cubic meters
'ounce'	Weight measure equal to 28.35 g
'pound'	Weight measure equal to 0.454 kg
'ton UK'	Weight measure equal to 1016.0469088 kg, also known as long ton, gross ton, shipper's ton
'ton US'	Weight measure equal to 907.18474 kg, also known as short ton, net ton
'degree'	Angle measure equal to π/180 rad

Examples

These examples show how the following key concepts are presented in IFC2X3, using IFCXML.

1. Identify, including the IFC object type, and its ‘owner’ history.

2. Grouping and classification

3. Functional measures

4. Impact indicators

5. Service Life

6. Other resources

Notes

By convention in IFC property and quantity names, and enumeration values in IFC are used:

1. Without spaces

2. In camel case (InCamelCase)

1 Identity

Product or assembly

IfcElement and ObjectType

IfcElementType and PredefinedType

Components are represented by the subtypes of ifcElement and IfcElementType. Each of these have attributes allowing selection from predefined enumerations and free text to further define the nature of the component.

<GlobalId>37N4UypQzHIfXhrSJ8E8EP</GlobalId>

</OwnerHistory>

<Name> Acoustical Panel Ceiling </Name>

<Description>Covering Acoustical Panel Ceilings example </Description>

</ObjectPlacement>

</Representation>

<ObjectType> Acoustical Panel Ceiling </ ObjectType >

</IfcCovering>

</OwnerHistory>

<Name>Acoustical Panel Ceiling</Name>

<Description>Covering Acoustical Panel Ceilings example</Description>

</HasPropertySets>

</RepresentationMaps>

<Tag>Acoustical Panel Ceilings example</Tag>

<PredefinedType>ceiling</PredefinedType>

</IfcCoveringType>

System, zone or part building

IfcZone, IfcSystem, IfcBuildingStorey

Systems and parts of the building are represented by the creation of groups which hold the constituent components and other groups.

<GlobalId>07N4UypQzHIfXhrSJ8E8EP</GlobalId>

</OwnerHistory>

<Name>Photovoltaic system 001</Name>

<Description> Photovoltaic system 001</Description>

</IfcSystem>

Facility

IfcSite, IfcBuilding

Facilities are represented by IfcBuilding, possibly one of many within an IfcSite or portfolio.

<GlobalId>37N4UypQzHIfXhrSJ8E8EP</GlobalId>

</OwnerHistory>

<Name>Hotel 003</Name>

<Description> City centre hotel</Description>

</IfcBuilding>

Portfolio

IfcProject, IfcGroup

Portfolios are represented by IfcProject which can contain many sites and buildings or by creating an IfcGroup of buildings.

<GlobalId>17N4UypQzHIfXhrSJ8E8EP</GlobalId>

</OwnerHistory>

<Name>My Company portfolio</Name>

<Description>UK Hotels portfolio</Description>

</IfcProject>

Homogenous material and construction (material layer set)

IfcMaterial, IfcMaterialLayerSet

Homgenous material and layered constructions are represented using IfcMaterial and IfcMaterialLayerSet. These can be associated to IfcElementType or IfcElement (see components) if necessary.

<Name>general aluminium</Name>

</IfcMaterial>

<Name>beam and block floor</Name>

</IfcMaterial>

</Material>

</IfcMaterialLayer>

<IfcMaterialLayer

<Name>screed</Name>

</IfcMaterial>

</Material>

</IfcMaterialLayer>

</MaterialLayers>

<LayerSetName>BEAM AND BLOCK FLOOR</LayerSetName>

</IfcMaterialLayerSet>

IfcOwnerHistory

Most objects can be associated to a detailed ownership. The following example uses both mandatory and optional fields.

<Id>C.Jones@Bath.ac.uk</Id>

<FamilyName>Jones</FamilyName>

<GivenName>Craig</GivenName>

<Role>userdefined</Role>

<UserDefinedRole>researcher</UserDefinedRole>

</IfcActorRole>

</Roles>

</IfcPerson>

</ThePerson>

<Description>University of Bath Sustainable Energy Research Team</Description>

</IfcOrganization>

</TheOrganization>

</IfcPersonAndOrganization>

</OwningUser>

</IfcOrganization>

</ApplicationDeveloper>

<ApplicationFullName>TSB Design and Decision Tool</ApplicationFullName>

</IfcApplication>

</OwningApplication>

<ChangeAction>added</ChangeAction>

</IfcOwnerHistory>

2 Grouping

Grouping defined by element type

See the section on Components

Grouping by association of Classification

Any classification can be associated to a portfolio, facility, system, component or material.

</OwnerHistory>

<Name>MF2004_CoveringTypeAcousticalPanelCeilings</Name>

<Description>classification of Covering Ceiling Acoustical Panel Ceilings according to MF2004</Description>

</RelatedObjects>

<Location>http://www.MF2004.com/tables#_95113</Location>

<Name>Ceiling coverings</Name>

<Source>MasterFormat</Source>

<Edition>2004 Edition</Edition>

</IfcCalendarDate>

</EditionDate>

<Name>MasterFormat2004</Name>

</IfcClassification>

</ReferencedSource>

</IfcClassificationReference>

</RelatingClassification>

</IfcRelAssociatesClassification>

Grouping by association of documents

For example all materials analysed by Bath ICE may reference the published documentation.

Grouping by association of library resources.

Web-services may be able to deliver DDT-LIB data.

Objects and property concepts may be assigned a globally unique identifier by buildingSMART IFD or other groups.

3 Functional Measures

Functional measures should be associated to each object. If there are none, the following assumptions may be made:

Materials are characterised as 1 cubic metre
Constructions are characterised as 1 square metre
All other objects are characterised as 1 “number of”.

However it is recommended that, as a minimum, portfolios, facilities and systems are characterised by the square metres of net internal area or gross internal floor area contained or served.

<GlobalId>1MiRAMajHEbRGjW8LX9b5z</GlobalId>

</OwnerHistory>

<Name>BaseQuantities</Name>

<Description>Base Quantities</Description>

<MethodOfMeasurement>Geometric measures</MethodOfMeasurement>

<Name>NetInternalArea</Name>

<Description>Net Internal Area</Description>

<Unit>

</Unit>

</IfcQuantityArea>

<Name>Students</Name>

<Description>Students in full time equivalent education</Description>

<Unit>

</Unit>

</IfcQuantityNumber>

</Quantities>

</IfcElementQuantity>

There is an exception for Ifc Material, which cannot have an Ifc Quantity Element associated, only Ifc Property Single Values. (To be confirmed).

</Material>

</NominalValue>

<Unit>

</Unit>

</IfcPropertySingleValue>

<Name>volume</Name>

<Description>volume</Description>

</NominalValue>

<Unit>

</Unit>

</IfcPropertySingleValue>

</ExtendedProperties>

<Description>basic quantities</Description>

<Name>BaseQuantities</Name>

</IfcExtendedMaterialProperties>

4 Environmental Indicators

These are similar to the functional measures. Some names are mandated in IFC by buildingSMART International, so agreement on others is needed.

The convention is that IFC property names contain no spaces but are capitalised.

<GlobalId>1MiRAMajHEbRGjW8LX9b5z</GlobalId>

</OwnerHistory>

<Name>Pset_EnvironmentalImpactValues</Name>

<Description>Environmental impact values of an element</Description>

<Name>MethodOfMeasurement</Name>

<Description>Method of measurement</Description>

</NominalValue>

</IfcPropertySingleValue>

<Name>NonRenewableEnergyConsumption</Name>

<Description>Quantity of non-renewable energy used as defined in ISO21930:2007 </Description>

</NominalValue>

<Unit>

</Unit>

</IfcPropertySingleValue>

<Name> ClimateChange </Name>

<Description>Quantity of greenhouse gases emitted calculated in equivalent CO2. </Description>

</NominalValue>

<Unit>

</Unit>

</IfcPropertySingleValue>

</HasProperties>

</IfcPropertySet>

Again, there must be an exception for IfcMaterial

</Material>

<Name>MethodOfMeasurement</Name>

<Description>Method of measurement</Description>

</NominalValue>

</IfcPropertySingleValue>

<Name>NonRenewableEnergyConsumption</Name>

<Description>Quantity of non-renewable energy used as defined in ISO21930:2007 </Description>

</NominalValue>

<Unit>

</Unit>

</IfcPropertySingleValue>

<Name> ClimateChange </Name>

<Description>Quantity of greenhouse gases emitted calculated in equivalent CO2. </Description>

</NominalValue>

<Unit>

</Unit>

</IfcPropertySingleValue>

</ExtendedProperties>

<Name>Pset_EnvironmentalImpactValues</Name>

<Description>Environmental impact values of a material</Description>

</IfcExtendedMaterialProperties>

5 Service Life

Service Life and other factors can be represented using IFC property sets.

<GlobalId>2hfLRDZAz8$QVWSrY4eISL</GlobalId>

</OwnerHistory>

<Name>Pset_ServiceLife</Name>

<Description>Captures the period of time that an artifact will last along with various factors that impact the expected service life.</Description>

<Name>ServiceLifeType</Name>

ACTUALSERVICELIFE: The service life that an asset has given.

EXPECTEDSERVICELIFE: The service life that an artefact is expected to have under current operating conditions.

OPTIMISTICREFERENCESERVICELIFE: The best or most optimistic estimate of service life that is quoted for an artefact under reference operating conditions.

PESSIMISTICREFERENCESERVICELIFE: The least or most pessimistic estimate of service life that is quoted for an artefact under reference operating conditions.

REFERENCESERVICELIFE: The typical service life that is quoted for an artefact under reference operating conditions. </Description>

<IfcLabel>REFERENCESERVICELIFE</IfcLabel>

</EnumerationValues>

</IfcPropertyEnumeratedValue>

<Name>ServiceLifeDuration</Name>

<Description>The length or duration of a service life</Description>

</NominalValue>

</IfcPropertySingleValue>

<Name>QualityOfComponents</Name>

<Description>Adjustment of the service life resulting from the effect of the quality of components used.</Description>

</NominalValue>

</IfcPropertySingleValue>

</HasProperties>

</IfcPropertySet>

[More needed]

6 Other resources

The complete file will have a number of supporting resource objects defined. For example, units not defined elsewhere can be found in the IfcUnitAssignment collection. This collection must have only one definition of length, area, volume etc. which can then be used as the default.

<Units>

<UnitType>planeangleunit</UnitType>

<Name>radian</Name>

</IfcSIUnit>

<UnitType>timeunit</UnitType>

</ValueComponent>

<UnitType>timeunit</UnitType>

<Name>second</Name>

</IfcSIUnit>

</UnitComponent>

</IfcMeasureWithUnit>

</ConversionFactor>

</IfcConversionBasedUnit>

</Units>

</IfcUnitAssignment>

(To follow: mandatory objects, making an object readable by BIM applications, etc.)

Reference Service Life is a simple attribute of an object.

An instance may have Service Life Factors A-G applied, or a single Factor.

Service Life Type	Enumeration	ACTUALSERVICELIFE: The service life that an asset has given. EXPECTEDSERVICELIFE: The service life that an artefact is expected to have under current operating conditions. OPTIMISTICREFERENCESERVICELIFE: The best or most optimistic estimate of service life that is quoted for an artefact under reference operating conditions. PESSIMISTICREFERENCESERVICELIFE: The least or most pessimistic estimate of service life that is quoted for an artefact under reference operating conditions. REFERENCESERVICELIFE: The typical service life that is quoted for an artefact under reference operating conditions.

	ACTUALSERVICELIFE
	EXPECTEDSERVICELIFE
	OPTIMISTICREFERENCESERVICELIFE
	PESSIMISTICREFERENCESERVICELIFE
	REFERENCESERVICELIFE
	OTHER
	NOTKNOWN
	UNSET
Service Life Duration	Duration	The length or duration of a service life.
Quality Of Components	Positive Ratio	Adjustment of the service life resulting from the effect of the quality of components used.
Design Level	Positive Ratio	Adjustment of the service life resulting from the effect of design level employed.
Work Execution Level	Positive Ratio	Adjustment of the service life resulting from the effect of the quality of work executed.
Indoor Environment	Positive Ratio	Adjustment of the service life resulting from the effect of the indoor environment (where appropriate).
Outdoor Environment	Positive Ratio	Adjustment of the service life resulting from the effect of the outdoor environment (where appropriate)
In Use Conditions	Positive Ratio	Adjustment of the service life resulting from the effect of the conditions in which components are operating.
Maintenance Level	Positive Ratio	Adjustment of the service life resulting from the effect of the level or degree of maintenance applied to components.

buildingSMART

Sections

Personal tools

Document Actions

buildingSMART UKI Sustainability Data for Design and Decision Tools for Low Impact Buildings.

Purpose

Background

Justification

Use cases

Objective

Objects

Outcome

Exclusions

Outline

Common file format.

Common terms

Object types

Attributes.

Classification systems

Units

Examples

Notes

1 Identity

Product or assembly

System, zone or part building

Facility

Portfolio

Homogenous material and construction (material layer set)

IfcOwnerHistory

2 Grouping

Grouping defined by element type

Grouping by association of Classification

Grouping by association of documents

Grouping by association of library resources.

3 Functional Measures

4 Environmental Indicators

5 Service Life

6 Other resources