Ventilation Component EPDs and Building LCAs

Keywords: EPD, ventilation products, c-PCR, LCA

The investigations conducted in CEN/TC 156 WG 26 have demonstrated the need for a principled approach toward ventilation component EPDs, where the intended use of EPDs for building LCAs remains the governing premise. Following the TC 156 Plenary meeting, this approach will be implemented through a standard series, with a WG 26 core standard and connected product group specific standards for addressing the Use stage.

This article is part 2 of a two-part series on the efforts toward a European standard for the EN 15804 complementary product category rules (c-PCR) for ventilation components. This part presents the current proposals from WG 26 and the suggested approach towards a coherent European framework, while part 1 addresses the context for the work and the key issues relating to the use of EPDs for ventilation components in building LCAs.

Overarching goals

In general, CEN/TC 156 WG 26 have been pursuing a set of overarching goals, creating a European framework for EPDs for ventilation components, with:

1.    Rules that deliver on what is demanded in the market

2.    Rules that promote better sustainability

3.    Rules that support digital workflows

4.    Rules that enable cost efficient EPDs

These goals provide a logical litmus test for different approaches and solutions, promoting the necessary due diligence when deliberating key issues of principled importance. The solutions discovered in WG 26, and put forth in the current core draft, will fulfil all of them. First and foremost, they will enable the full and coherent inclusion of ventilation components in building LCAs, according to the EPBD and EN 15978. Compliance with EN 15804 is a prerequisite.

Secondly, they will promote better sustainability and continuous environmental improvement by ensuring that the EPDs contain accurate and non-misleading environmental information for building level optimisation. Minimising the risk of EPD misuse, and consequent sub-optimal selection of ventilation products and solutions based on faulty, non-valid environmental information, is key in achieving this goal.

Thirdly, the selected approach fully supports digital workflows, for both EPD owners and EPD users. This is a prerequisite (but not in itself enough) for achieving the last overarching goal: cost efficient creating and updating of EPDs. With “Digital by default” being a key principle in EU regulations going forward, supporting digital workflows is also important for achieving a robust and stabile framework with regards to future updates and required changes.

Finally, the c-PCR standard will ensure cost efficient compliance and inclusion in the new building LCA paradigm in Europe. The intrinsic value of having a standard will make the biggest impact, reducing the number of EPDs necessary down to one per product. However, investigations and thorough deliberations have resulted in solutions which has the potential of dramatically reducing the unnecessary burden on the manufacturers, even when compared to the most cost-efficient and rational local EPD setups today.

EPD Type

The recommended EPD type in the core standard will mandate the inclusion of A1-A4, and C1-C4 and D, leaving the B-stages and other modules optional for the manufacturer to declare.

Common Use stage scenarios are not defined in the WG 26 core standard. Instead, the B modules are to be addressed in connected product group specific standards where relevant. Until such standards are available, EPDs should be possible to develop on the basis of the WG 26 core standard, utilising the Additional technical information in the EPDs for inclusion of key product performance parameters (or the sources to such), for the proper project specific assessment of the Use stage (Figure 1).

Figure 1. EPD type & Life Cycle Modules included.

Additional information

The quantified environmental impact data is not the only format available in the EPDs. The calculated environmental impact is accompanied with “Additional information not derived from LCA”, including “Additional technical information” which is defined as “information …characterising the product’s technical and functional performance during the life cycle stages other than the product stage…”.

Additional technical information could be addressed as a mandatory requirement in the core standard. Smartly applied and described for the respective ventilation components, this provision provides a suitable vessel within the EPDs for communicating key product performance characteristics relating to energy efficiency, energy use and last but not least heat recovery. It also provides a practical bridge between the WG 26 core rules and the connected product group specific standards to be developed for the possible inclusion B-stage scenarios.

The environmental impact from energy consumption and heat recovery must be handled with the required precision and care, calculated on a building level through detailed project specific energy calculations. This is indeed a mandatory part of the building LCAs. In addition to the embedded environmental footprint of the products, the recommended approach ensures that EPDs will contain information (or information sources) necessary to promote and enable such calculations on a building level - also when EPDs are produced on the basis of the core standard, before potential product group specific standards are available.

Some examples of suggested Additional information are listed in Table 1.

Table 1. Proposed mandatory Additional information.

Declared units

The quantified environmental impact data in EPDs, including all the prementioned environmental indicators, are declared per a defined unit of measure (unit of declaration).

Ventilation products are usually grouped in product families, where essentially the same product is offered in different sizes and capacities. Passive products are typically offered in a wide range of nominal duct sizes, while active products cover broad capacity ranges. Today, EPDs are usually issued per piece of product, with one EPD per size.

However, WG 26 has shown, through analysing existing ventilation product EPDs, that weight and embedded emissions have a close to linear relationship within product families, across all environmental indicators in the EPDs. This has been demonstrated for both passive and active components, with one example in Figure 2 (extract from twelve separate EPDs within the same AHU product family).

Figure 2. Example of weight and emissions linearity.

The conclusion from this finding is stark: In a twelve size AHU range within the same family and basic configuration, as shown in Figure 2, all but one EPD constitutes an inefficient use of time, resources and effort. The same is of course true for less complex products as well.

The possible solution is simple: For ventilation all components, WG 26 recommends declaring EPDs on the basis of weight (per kg of product). This enables product family EPDs as opposed to one EPD per size (Figure 3).

Figure 3. Product family EPDs.

This approach would dramatically reduce the bureaucratic burden on the European ventilation industry, potentially reducing the number of EPDs required by order of magnitude. The use of EPDs is made equally simple: In a building LCA setting, the environmental information in the EPD is simply multiplied with the specific weight of the product in question. Weight is readily available in all types of documentation and BIM-objects, and if needed, the weights can be listed in the EPDs themselves.

There are exceptions to this approach, which need to be accounted for. Not all product families have a linear enough relationship between weight and material composition. For variants that falls outside of the required linearity of “family EPDs”, the possibility to declare “per piece” EPDs will also be available.

A prerequisite for this cost-efficient and highly rational approach is the EPD type prescribed, and that the LCA derived information (declared life cycle stages and modules) is limited to embedded environmental impact, as mandated by the core standard.

Structure

The structure for the c-PCR framework (Figure 4), as recently decided by CEN/TC 156, will be as follows; One “core” standard from WG 26, supplemented with additional standards for product group specific Use stage requirements developed by the respective CEN/TC 156 Working groups. EN 15804 still apply, in full.

Figure 4. Structure & c-PCR standard series.

All common issues should be covered horizontally for all product types in order to minimize vertical (branch specific) deviations. The decision to organise the work as a standard series does not change this principle. Rather, it makes it even more important to distinguish between rules that can be solved in common, and rules that require product group specific provisions. Presumably this is to maintain a manageable and efficient setup for all stakeholders involved, including legislators, manufacturers and users of EPDs. The complex and hard to manage situation which emerges, if every ventilation product category should have its own distinct set of special requirements - beyond what is necessary - is not hard to imagine.

For the ventilation components within the scope of CEN/TC 156, there are some very important common denominators that enables a horizontal approach. Individually, and on their own, ventilation components usually provide limited value. However, when combined into functioning systems in buildings, they become crucial. Not only for achieving healthy indoor environments, but also crucial for energy efficient buildings, and indeed also crucial for achieving a more sustainable construction sector. This context is key, especially within the new paradigm of Life Cycle Assessments and EPDs.

Other common denominators include manufacturing companies, material makeup, production methods, upstream and downstream supply chains, where large overlaps can be found between the respective product groups.

Depending on the approach of other WGs, the scope of LCA information in the EPDs and mandatory declared Life Cycle modules can still be solved with a common approach, enabling the holistic assessment of products in their right context based on accurate and non-misleading information. The common core WG 26 framework is equally suitable for both active and passive components. It also enables and promotes the proper assessment of the all-important Use stage Operational energy use, calculated for the building with project specific variables. This includes taking into account the positive effects of heat recovery.

Using weight as basis for the LCA derived quantified environmental data (LCA results) is equally beneficial for all product groups, enabling cost-efficient creation and maintenance of EPDs on behalf of the manufacturers. Declaring impact “per piece” will be available when single products fall outside the required linearity for a family EPD. Ducts are the exemption, best declared “per meter” as opposed to “per piece”. Any additional Use stage requirements imposed by the additional standards will require a re-assessment of this.

Closing comments

Having EPDs will be optional from a regulatory standpoint. However, from a market perspective, EPDs are likely to become a question of purchasing hygiene in several key markets in Europe. With ventilation systems representing large quantities of materials being delivered to the building site, required inclusion in the building LCA should be expected. A large and steadily growing portfolio of ventilations component EPDs exist already.

With the EPBD deadline for building LCAs looming (1 January 2028), timeline and standardisation efficiency is also an underlying goal for WG 26. It has therefore been decided to tackle the most urgent issues in the first draft and postpone other issues to later revisions. For European manufacturers, and indeed also users of EPDs, it is important to get the first core standard issued as soon as possible, enabling the cost-efficient inclusion of ventilation components in building LCAs – which sooner or later will be required. The immediate objective should be that the WG 26 core standard enables EPDs to be developed on its basis, until product group specific standards with additional requirements become available.

The proposed approach aims to support the intended use of EPDs in building LCAs, while at the same time reducing unnecessary cost and complexity for manufacturers. The purpose is not to simplify the assessment of environmental impact, but rather to ensure that the assessment is conducted in the right context, based on accurate and non-misleading information.

The Use stage environmental impact from ventilation systems must ultimately be assessed on a building level, through detailed project specific energy calculations considering the effects of heating, cooling and heat recovery. The role of the ventilation component EPDs should not be to replace such calculations, but to support them through coherent and reliable environmental information suitable for use in the broader building LCA framework.

To have any purpose at all, it is important that ventilation component EPDs ends up supporting the goal of continuous environmental improvement for the construction sector. This requires a principled approach to both ventilation components and ventilation systems, and the role that accurate product performance data and energy calculations must play in order to achieve optimised solutions on a building level.

The whole standard series should be developed with this same objective, maintaining the principle of one EPD per product, valid across Europe. To this end, the other Working groups are invited to adopt the four Overarching goals in their upcoming endeavours. When evaluating how to deal with the Use stage for their respective products, they should keep in mind that a complex and expensive calculation procedure that produces figures with seemingly high precision - but with no validity in any project - inevitably undermines trust. The industry has a shared responsibility to state this clearly.

The context and backdrop of these recommendations is presented in part 1 of this article series.