IMPACT for Life Cycle Assessment (LCA)

IMPACT is a specification and database for software developers to incorporate into their tools to enable consistent Life Cycle Assessment (LCA) and Life Cycle Costing (LCC). IMPACT compliant tools work by allowing the user to attribute environmental and cost information to drawn or scheduled items in the BIM. Put simply, IMPACT takes quantity information from the BIM and multiplies this by environmental impact and/or cost ‘rates’ to produce an overall impact and cost for the whole (or a selected part) of the design. The results generated by IMPACT allow the user to:

  • analyse the design to optimise cost and environmental impacts.
  • compare whole-building results to a suitable benchmark to assess performance, which can be linked to building assessment schemes.

The overall aim of IMPACT is to integrate Life Cycle Assessment, Life Cycle Costing and Building Information Modelling.

For more information, please visit www.IMPACTwba.com

The IMPACT Database

BRE Centre for Sustainable Products has completed an update of the IMPACT Database (IMPACT DB) for construction products. Version 5, released in March 2018, supersedes version 4. The IMPACT DB contains approximately 350 datasets that are compliant with EN 15804[1] and have been modelled in SimaPro, using BRE Global EN 15804 PCR[2], ecoinvent v3.2[3] and various Trade Association / representative manufacturers’ primary data where applicable.

The IMPACT DB fulfils data quality requirements of EN 15804 for product-level environmental data, and is applicable to building-level environmental assessments using EN 15978:2011.

The key difference between IMPACT DB v5 and v4 is summarised as follows:

  Version 5 (New) Version 4
Method BRE Global EN 15804 PCR Rev 2.0 BRE Global EN 15804 PCR, Rev 0.0
Background database ecoinvent v3.2 ecoinvent v3.1
Software SimaPro SimaPro

In modelling the construction products, some compensation steps were necessary:

  • BRE Centre for Sustainable Products has adapted, where relevant, the datasets (which are representative of Europe) to be representative of UK production by adjusting on a case-by-case basis specific material and energy inputs based on publicly available information and historical production data held by BRE.
  • For products that are typically imported from specific countries, in the absence of country specific data the adjustment has implied using regionally appropriate raw materials and energy input data.
  • For construction products that are internationally traded, e.g. metals, the respective European or global average ecoinvent v3.2 datasets have been used without adjustment.

Other specific aspects to note:

End of life scenarios

The data for the scenarios used for waste from construction, refurbishment and demolition have been derived from BRE SMARTWaste statistics. Overall this data is comparable to the UK statistics published from Defra in 2016. Licenced IMPACT DB users may obtain specific end of life percentages and final disposal routes for individual materials directly from BRE Sustainable Products.

Default installation wastage percentages are also included for applicable materials in the IMPACT DB, also based on BRE in-house data (Resource Efficiency team).

Carbon sequestration of bio-based products

The IMPACT DB takes into account the storage of carbon in biomaterials such as timber. The sequestered carbon is an inherent physical property of the biomaterial and leads to the reporting of net negative CO2 emissions values for these products, especially in instances where the manufacturer-related processes do not contribute sufficiently significant carbon dioxide emission values.

Carbonation of CaO and Ca(OH)2-containing products

The IMPACT DB takes into account the carbonation of products containing calcium oxide or calcium hydroxide, e.g. concrete. This uptake of carbon dioxide from the atmosphere is applicable to surfaces exposed to air and is dependent on the porosity and the strength of the product.

International transport

The transport of construction products that are imported into the UK from specific countries (e.g. China / India) is accounted for in the respective datasets.

A further update planned for summer 2018 will include data from EN 15804 compliant EPDs as well as critically reviewed LCA studies compatible with the existing IMPACT DB.

Envest2

Envest 2 is a software tool that informs the design process to deliver buildings with low environmental impact and whole-life cost. It makes explicit the environmental and financial trade-offs in the design process, allowing the client to optimise the final design according to their priorities.

Envest is web-based allowing design teams to store and share information in a controlled and accessible way, enabling benchmarking and design comparison. Envest is based on Environmental Profiles data and certified Environmental Profiles data for manufacturer’s products can be used within Envest to model impacts within a building.

For a free demonstration, go to http://envest2.bre.co.uk/

[1] BS EN 15804:2012+A1:2013

[2] BRE Global EN 15804 Product category Rules (PCR), PN514 Rev 2.0 (pub January 2018)

[3] ecoinvent v3.2 is a publicly available, research-based, peer-reviewed (and open to scientific scrutiny and dialogue) and therefore scientifically robust database that can be used for the life cycle assessment of construction products.

For more information

Call us on 0333 321 88 11
or email Kim Allbury