Background and general considerations about life cycle thinking in construction
Rakennusteollisuus RT ry (RT) thanks you for the opportunity to express your views on the draft as a method for evaluating the carbon footprint of buildings. Rakennustuoteollisuus RTT ry (RTT), as a part of RT, is responsible as SFS's industry community for European standardization related to the life cycle assessment of buildings (CEN's technical committee TC 350 and its essential standards EN 15643 series, EN 15978 and EN 15804), the application of which has been referred to in YM: in the method instruction. Regarding the standards, RT's considerations are based on familiarity with their rules and in-depth knowledge of their application, but at the same time also on identifying the uncertainty factors of the assessment.
In its statement, RT has also taken into account the ongoing MRL reform work, and especially the discussion related to the life cycle and low-carbon construction in the Construction division, and the already presented draft articles. In addition to evaluating the carbon footprint of buildings, YM's goal is to set emission targets based on the evaluation methods in question (low-carbon limit values for building types). These require transparency from the evaluation method, credibility and clarity from the input data and calculation parameters used in it, and reliability of the results, also from a legal perspective. In addition, the aforementioned the purpose of the regulation is to affect the calculation parameters affecting the essential evaluation results by tabulating/standardizing them.
In the current overall reform of the Land Use and Construction Act, the life-cycle thinking has been strongly emphasized. YM states in its own reasons:
- Life cycle thinking refers to the evaluation of the effects of the building and its use as well as the entire life cycle of construction products from the perspectives of sustainable development. The life cycle of a building includes manufacturing and transportation of building materials, construction, operation and maintenance, repairs, demolition work and utilization or final disposal of demolition waste. The negative and positive effects during the life cycle of the building can be evaluated from the point of view of ecological, social and financial sustainability. Although the focus is often on reducing environmental loads, consumption of natural resources, harmful emissions and indirect effects on human health or biodiversity, life cycle quality includes e.g. quality factors concerning the condition, usability and service life of the building. Quality factors include, for example, the quality of the interior, accessibility, conversion flexibility and the service life of structures and systems. Cultural, aesthetic and architectural values are also part of life cycle thinking. The life-cycle thinking approach embodies the goal of moving from partial optimization to a more comprehensive and sustainable impact and cost analysis in construction.
RT considers it of the utmost importance to find out how important factors related to life cycle quality (or sustainable quality of construction) are actually taken into account and put into practice. The method instruction now in the statement as part of the regulation related to life cycle thinking focuses only on the carbon footprint in a limited and simplified way.
RT considers it worrisome that guidance focusing solely on the carbon footprint is intended to be put into practice by setting low-carbon limit values or by rewarding a smaller carbon footprint, while comparison of different solutions would be allowed (the so-called functional equivalence would be met) if the construction regulations (minimum) were met. Both of the above at worst, these practices would have the effect that all construction exceeding the minimum requirements of the construction regulations and bringing different added value to the life cycle quality would become unattractive. RT considers that this kind of development cannot be considered desirable from the point of view of society, even when aiming for climate-friendly construction.
RT supports the development of standardized baseline data and standardized life cycle assessment tools that cover the entire life cycle of a building in promoting low-carbon construction. However, according to RT's view, the procedure based on life cycle assessment (LCA) according to the instructions in the statement still needs to be developed considerably before it can be used in regulatory guidance promoting construction sustainability and life cycle quality. The several uncertainty factors related to the life cycle assessment of the notes and the problems related to the verification of the results, it is also worth considering the general credibility of the method as a regulatory control tool.
Summary of key considerations
Now, in addition to the limitations of the calculation and the chosen methods, the effects of the quality of the initial data and the analysis of uncertainties affect the interpretation of the results. Since these starting data for the calculation are still incomplete, vague and/or unpublished, RT only comments on the evaluation method itself at this stage. RT will also present its attention to the essential cost-benefit analyzes related to the implementation of the method instruction later.
The procedure should be developed in at least the following ways so that its application would be meaningful, i.e. that it would produce a positive control effect from the point of view of society, also justified in terms of cost effectiveness:
1.
No validation of any kind (accuracy, influence of different factors/parameters, reproducibility) has been required for the evaluation method to demonstrate the reliability of the results. No verification or verification procedure has been assigned to the life cycle assessment results (their reliability) calculated in accordance with the method guideline.
Justification:
It is a method description, which should present the accuracy and repeatability of the method, etc. related factors and means that improve the reliability of the calculation and guarantee reliability (verification). If different calculators use the method to evaluate the same object, how big can the difference between the results be without one or more calculating incorrectly. The evaluation method referred to in the legislation should also be defined and described in such a way that the work of those acting according to the instructions is not questioned, especially in peer evaluations. The starting point for improving the reliability of the results of the assessment method cannot be the tabulation/standardization of everything, which only leads to worse unreliability and speculativeness of the results (as the simplified method does).
Solution:
A validation program is drawn up for the evaluation method before implementation, which demonstrates the general usability of the method as part of the regulation and the reliability of the results given by different calculation methods. The issue is of great legal importance, as well as in terms of setting and credibility of low-carbon limit values.
2.
The draft of the method instruction lacks a clear description of on what basis and at what stage the different calculation methods presented and permitted by the method instruction are used, especially from the point of view of the reliability and credibility of the calculation results. This observation is also essentially related to the previous point 1).
Justification:
the assessment method actually includes three different calculation methods: Simplified and detailed assessment and a "hybrid" that applies both. The method instruction states that "a simplified carbon footprint assessment can be used at the beginning of the planning project" and that "when the building is commissioned, the assessment can be updated with more detailed information". What is the basis and ultimately the goal for a simplified and on the other hand a more detailed evaluation? The decision about the building's main materials is made early on, and then the "emissions ceiling" for such an assessment is also fixed. The measures and sanctions remain unclear in a situation where the detailed assessment that may be made in connection with the commissioning of the building shows that the emission ceiling has been exceeded. It also remains unclear who will ensure the correctness of the evaluation result based on theoretical calculation and staying within the set low-carbon limit values throughout the building's long service life.
A simplified assessment does not even require a quality assurance procedure, whereas in a detailed assessment it is required in some form. However, both calculation methods can be used in the essential decision-making stages and in the building permit stage to meet the low-carbon limit value requirements specific to the building type.
Solution:
The simplified assessment method should be removed from the method instruction as it is imprecise. Before implementing the refined method, it must be clarified how the important factors related to life cycle quality are actually taken into account and included in the evaluation method.
3.
The standard lifetimes presented in the draft guide you to optimize the lifetime to the given dimension. However, 50 or 75 years is a rather short target age for buildings, which can be seen in the current debate about the major renovation and demolition needs of buildings of that age.
Argument:
If we only look at the carbon footprint in building control, the standardized service lives lead to optimizing the service life to the given dimension, because a large part of the factors affecting the longer and more flexible use of buildings (e.g. improving conversion flexibility, facades resistant to weather stress, comfort, safety and health factors) increase the carbon emissions of materials; their benefits only come to the fore at different stages of the long usage phase, and especially at the end of the first life cycle. There are already builders in Finland who build on their own balance sheet and require their buildings to have a useful life of at least 100 years.
Similarly, standardizing the service life removes the incentive to produce service life information that is inevitably required for reasonable life cycle calculations and gives an incorrect picture of the service life of structural solutions that actually have a shorter service life than the standard service life.
Solution:
The best solution would be for the standard lifetimes of buildings to be removed and replaced with actual life cycle lengths of the structural solutions used at any given time, verified by generally accepted procedures (credible standardized lifetime measurement). If this is not possible, the calculation should at least be changed so that the standardized service life requirement is the minimum of the calculation and it would be possible to do the calculation with the service life requirement set by the customer.
In addition, the life cycle carbon footprint must be divided by the life of the building, so that the procedure would meaningfully give a true picture of the building's carbon footprint.
4.
The procedure according to the preliminary guideline draft (section 2.14), in which all solutions that meet the construction regulations are considered functionally equivalent and the evaluation results would be compared with each other in relation to the emission ceiling specific to the building type, would produce a very strong negative effect on the quality of construction. It would also have a negative impact on innovations that develop life-cycle quality, without even a 1% reduction in Finland's greenhouse gas emissions being achieved.
Argument:
The guidance, which only looks at CO2 emissions, encourages the construction of buildings that precisely meet the minimum requirements. Construction that exceeds all the minimum requirements of the construction regulations becomes unattractive with this kind of control, because a large part of the real improvements in durability are achieved by increasing the amount of materials.
The evaluation method does not take into account and at the same time the control effect penalizes, for example, the construction of better structural safety, frame flexibility, higher floor height or span that serves functionality, or better sound insulation. Similar examples of a very harmful control effect can be found in countless numbers.
Against this background, setting the low-carbon limit values proposed by the legislation for each type of building is very demanding and difficult to justify.
Solution:
As part of the procedure, a functional way must be created to take into account the functional properties of the solutions/structures under consideration as part of the life cycle quality of construction and buildings. It is essential to take into account the harmful emissions highlighted by YM itself, both during the use phase and at the end of the life cycle, indirect effects on human health or biodiversity, and life cycle quality-related e.g. quality factors concerning the condition, usability and service life of the building. Further quality factors include, for example, the quality of the interior, accessibility, conversion flexibility and the service life of structures and systems.
Taking into account the above, several low-carbon limit values given by building type have to be determined and in such a way that their levels depend on the above. of quality factors. This means that the limit values can be at most goal-oriented, not binding.
5.
When viewed in the manner presented in the method guide, one key goal of construction control, the promotion of the circular economy, is not realized.
Argument:
In the evaluation procedure, the net benefits resulting from the use of reusable building parts or recyclable materials are reported as separate additional information, which is not deducted from the carbon footprint of the building's life cycle. The control effect of this does not encourage looking for solutions for the reuse of materials.
The evaluation procedure also does not take into account the real utilization potential of the building materials according to the waste hierarchy, nor the real recycling rate, nor the impact of harmful substances contained in the building materials on material recycling or reuse, although it requires the presentation of detailed, implausible end-of-life environmental impact information (so-called module C). If, as a result of the simplified procedure, decisions about structural solutions and other choices were made on the basis of table values alone, how could the assessment take any position on the benefits/disadvantages of the end of the life cycle.
Solution:
The examination of the portion that comes after the end of the building's life cycle (so-called module D) should be changed to such that it encourages an increase in the recycling rate of building products and, if possible, also an increase in the utilization rate of the building (convertibility and reuse of the building/building frame). Co. the module should also take into account the characterization of materials as waste and its effect on utilization as material/waste.
6.
When referring to EN standards, the requirement is compliance with their rules; the making of deviations must be justified and indicate the potential shortcomings of the standard.
The method instruction also questionably interprets the requirements of the standards regarding the fulfillment of functional equivalence. Comparability of buildings requires that they are functionally equivalent. The method guideline states that functional equivalence is fulfilled when the building regulations are fulfilled by building type. This cannot be considered as the starting point for sustainable construction and the development of life cycle quality, as RT states in section 4.
The essential factors and requirements related to service life (service life dimensioning) have been left unsubstantiated and presented vaguely; however, they are one of the most essential parts in the development and improvement of sustainable construction and life cycle quality (see section 3).
According to the method instructions, scenarios deviating from the rules of the EN standards can be prepared for the use of energy, but e.g. for end-of-life (module C) and non-life-cycle (module D) benefits no; the matter has not been adequately and credibly justified. The method of calculating energy use is unclear as a whole and requires a wider expert discussion.
Other considerations
RT also wants to draw the attention of the Ministry of the Environment to the magnitude of the emission reduction that can be achieved by regulating the carbon footprint of new construction and to the cost-benefit analyzes of regulatory development that are still missing. This is essential when motivating different actors to produce the relatively expensive initial data required by the evaluation method.
According to independent studies, the lifetime emissions of apartment buildings built from different materials are practically the same; if differences do arise, they are also underpinned by different calculation parameters and speculative default values that increase the uncertainty of the results. This is the case even if the energy during use would already become low-emission in the near future (reference: Sitra report 63).
YM states in its background memorandum that different control methods for promoting low-carbon construction have been studied in different studies (Bionova, 2017, RTY, 2017 and VTT, 2018)). According to the assessment of the impact of different control measures for low-carbon construction, the most effective results would be obtained by setting carbon footprint limit values for each building type. RT considers that the aforementioned the reports have been prepared by life cycle consultants under the guidance of YM and without sufficient evaluation and commenting by relevant stakeholders. Their conclusions only partially represent the construction sector's view on the development of sustainable construction and life-cycle quality, the promotion of low-carbon building stock and the key factors influencing it.
RT also points out that the background memo of the evaluation method incorrectly states that RTT was represented in the method work. RTT's expert has participated in the work as an expert of the relevant life cycle assessment EN standards (CEN Technical Committee TC 350) and has not represented RT and RTT in the work. Finally, RT suggests that in the further development of the method instruction, a broader knowledge of the real estate and construction sector and its processes as well as construction material technology should be represented.
In addition to the fundamental development needs mentioned above, the evaluation procedure contained in the opinion has a significant number of smaller points that require clarification. RT will comment on these in the future in the further development work of the method instruction, in which it will gladly participate.
More information about the statement:
Pekka Vuorinen
pekka.vuorinen@rakennusteollisuus.fi
Statement in pdf format:
Statement on the draft carbon footprint assessment method for buildings