Byggandet står för en betydande resursanvändning och miljöbelastning. Att uppföra en större andel av byggnadsstommarna av trä har lyfts som ett möjligt sätt att bidra till ett mer hållbart byggande. Städer har engagerat sig i byggande med trä genom att anta särskilda träbyggnadsstrategier. För att fatta välinformerade beslut om val av byggnadsstommar behöver beslutsfattare vetenskapligt grundade kunskaper. Det saknas i litteraturen ett sammanställt vetenskapligt kunskapsunderlag vad gäller trästommars tekniska prestanda och hållbarhet. Den här rapportens syfte är att utgöra ett sådant underlag.

More use of biobased materials has been proposed as important for reducing the high resource use and severe environmental impact of buildings. For increased and sound use of biobased building materials, decision makers need information on their technical and sustainability performance – but there is a lack of an updated synthesis of such information in the scientific literature. Therefore, this project has gathered scientific knowledge on the technical and sustainability viability of biobased building materials, with a focus on load-bearing structures.

Specific objectives were to:

a) Clarify technical challenges that bio-based building frames have been associated with, and how these have been handled.

b) Clarify the sustainability impact of bio-based building frames, in a life-cycle perspective, compared to non-bio-based building frames.

c) Explore the opportunities for bio-based building frames to be part of a circular economy, in terms of their reusability and recyclability.

Production of cotton and synthetic fibres are known to cause negative environmental effects. For cotton, pesticide use and irrigation during cultivation contributes to emissions of toxic substances that cause damage to both human health and the ecosystem. Irrigation of cotton fields cause water stress due to large water needs. Synthetic fibres are questionable due to their (mostly) fossil resource origin and the release of microplastics. To mitigate the environmental effects of fibre production, there is an urgent need to improve the production of many of the established fibres and to find new, better fibre alternatives.

For the first time ever, this reports compiles all currently publicly available data on the environmental impact of fibre production. By doing this, the report illuminates two things:

• There is a glaring lack of data on the environmental impact of fibres – for several fibres just a few studies were found, and often only one or a few environmental impacts are covered. For new fibres associated with sustainability claims there is often no data available to support such claims.
• There are no ”sustainable” or ”unsustainable” fibre types, it is the suppliers that differ. The span within each fibre type (different suppliers) is often too large, in relation to differences between fibre types, to draw strong conclusions about differences between fibre types.

Further, it is essential to use the life cycle perspective when comparing, promoting or selecting (e.g. by designers or buyers) fibres. To achieve best environmental practice, apart from considering the impact of fibre production, one must consider the functional properties of a fibre and how it fits into an environmentally appropriate product life cycle, including the entire production chain, the use phase and the end-of-life management. Selecting the right fibre for the right application is key for optimising the environmental performance of the product life cycle.

The report is intended to be useful for several purposes:

• as input to broader studies including later life cycle stages of textile products,
• as a map over data gaps in relation to supporting claims on the environmental preferability of certain fibres over others, and
• as a basis for screening fibre alternatives, for example by designers and buyers (e.g. in public procurement).

For the third use it is important to acknowledge that for a full understanding of the environmental consequences of the choice of fibre, a full cradle-to-grave life cycle assessment (LCA) is recommended.

The production of cotton and other fibers causes excessive resource use and environmental impacts, and the deployment of these fibers in “fast fashion” is creating large masses of textile waste. Therefore, various industrial researchers are attempting to develop systems to recycle cellulosic materials. This is a challenging undertaking because of the need to handle mixed waste streams. Alkaline hydrolysis has been suggested as a useful textile recycling process, but its sustainability credentials have not been fully examined via life cycle assessment. The aim of this article is to provide such an examination and to guide process developers by scaling up results from recent laboratory work to a small-scale industrial facility. The results indicate that the recycling process is promising from an environmental point of view. The key issue controlling the relative environmental performance of the recycling system in comparison to a single-use benchmark is how the process for converting recovered cotton into a cellulosic fiber is performed. A fully integrated viscose production system or a system that makes one of the newer cellulosic fibers (e.g., lyocell) from the recovered cotton will improve the performance of the recycling system relative to its alternatives.

Purpose: This article aims to explore how different assumptions about system boundaries and setting of baselines for forest growth affect the outcome of climate impact assessments of forest products using life cycle assessment (LCA), regarding the potential for climate impact mitigation from replacing non-forest benchmarks. This article attempts to explore how several assumptions interact and influence results for different products with different service life lengths. Methods: Four products made from forest biomass were analysed and compared to non-forest benchmarks using dynamic LCA with time horizons between 0 and 300 years. The studied products have different service lives: butanol automotive fuel (0 years), viscose textile fibres (2 years), a cross-laminated timber building structure (50 years) and methanol used to produce short-lived (0 years) and long-lived (20 years) products. Five calculation setups were tested featuring different assumptions about how to account for the carbon uptake during forest growth or regrowth. These assumptions relate to the timing of the uptake (before or after harvest), the spatial system boundaries (national, landscape or single stand) and the land-use baseline (zero baseline or natural regeneration). Results and discussion: The implications of using different assumptions depend on the type of product. The choice of time horizon for dynamic LCA and the timing of forest carbon uptake are important for all products, especially long-lived ones where end-of-life biogenic emissions take place in the relatively distant future. The choice of time horizon is less influential when using landscape- or national-level system boundaries than when using stand-level system boundaries and has greater influence on the results for long-lived products. Short-lived products perform worse than their benchmarks with short time horizons whatever spatial system boundaries are chosen, while long-lived products outperform their benchmarks with all methods tested. The approach and data used to model the forest carbon uptake can significantly influence the outcome of the assessment for all products. Conclusions: The choices of spatial system boundaries, temporal system boundaries and land-use baseline have a large influence on the results, and this influence decreases for longer time horizons. Short-lived products are more sensitive to the choice of time horizon than long-lived products. Recommendations are given for LCA practitioners: to be aware of the influence of method choice when carrying out studies, to use case-specific data (for the forest growth) and to communicate clearly how results can be used.

This paper reviews studies of the environmental impact of textile reuse and recycling, to provide a summary of the current knowledge and point out areas for further research. Forty-one studies were reviewed, whereof 85% deal with recycling and 41% with reuse (27% cover both reuse and recycling). Fibre recycling is the most studied recycling type (57%), followed by polymer/oligomer recycling (37%), monomer recycling (29%), and fabric recycling (14%). Cotton (76%) and polyester (63%) are the most studied materials.

The reviewed publications provide strong support for claims that textile reuse and recycling in general reduce environmental impact compared to incineration and landfilling, and that reuse is more beneficial than recycling. The studies do, however, expose scenarios under which reuse and recycling are not beneficial for certain environmental impacts. For example, as benefits mainly arise due to the avoided production of new products, benefits may not occur in cases with low replacement rates or if the avoided production processes are relatively clean. Also, for reuse, induced customer transport may cause environmental impact that exceeds the benefits of avoided production, unless the use phase is sufficiently extended.

In terms of critical methodological assumptions, authors most often assume that textiles sent to recycling are wastes free of environmental burden, and that reused products and products made from recycled materials replace products made from virgin fibres. Examples of other content mapped in the review are: trends of publications over time, common aims and geographical scopes, commonly included and omitted impact categories, available sources of primary inventory data, knowledge gaps and future research needs. The latter include the need to study cascade systems, to explore the potential of combining various reuse and recycling routes.

Purpose: A cradle-to-gate, input/output-based social life cycle assessment (SLCA) was conducted using the Swedish clothing consumption as a case study. The aim was to investigate the influence of the cut-off rule and the definition of “hotspots” in social hotspot assessment. A second aim was to identify social hotspots of Swedish clothing on a national level. Methods: The case study was based on the SLCA methodology provided in the Guidelines for Social Life Cycle Assessment of Products (Benoît and Mazijn 2009). An input/output model was used to define the product system from cradle to gate. The negative social hotspots were evaluated for a set of social indicators that were selected by consumers. The impact assessment was conducted on a sector and country level by using the Social Hotspots Database. The identified sectors of the economy with high and very high levels of risk were listed for each social indicator. Results and discussion: The results pinpointed some hotspots throughout the supply chain for Swedish clothing consumption. Some unexpected sectors such as commerce and business services in Bangladesh were identified as important hotspots as well as main sectors in the production phase such as plant fibres, textiles and garments that would be expected also on the bases of a traditional process analysis. A sensitivity analysis on different cut-off values showed the extent to which the choice of cut-off rule can directly affect the results via influence over the number of country-specific sectors (CSSs) in the product system. The influence of the hotspot definition was investigated by evaluating the working hour intensity for low- and medium-risk levels for three different indicators. The results show that for child labour, 92 % of the share of working hours was associated with low- and medium-risk levels. Therefore, the evaluation of risk levels other than high and very high can provide a more complete picture of the hotspots. Conclusions: The application of input/output-based SLCA on the clothing production supply chain provided a more complete picture of the social hotspots than with traditional process-based SLCA. Some unexpected sectors related to commerce and business appeared as social hotspots in the clothing industry. The study explored some important parameters in applying an input/output-based SLCA. The results show that the cut-off values and definition of hotspots in relation to risk levels can directly influence the results. 

This report summarises the environmental assessment work done in the Mistra Future Fashion program focussed on the potential to improve the environmental performance of garments and adapt them to a circular economy. The approaches examined in this report include reducing the environmental impacts from fast-fashion trends by making garments from paper-based materials, or by extending garment life cycles.

This assessment considers two paper-based garments. One is made primarily from paper pulp but enhanced with a polylactic acid polymer. This garment is worn between two to five times before being recycled as newspaper. The other fast garment is made of paper pulp, polylactic acid and nanocellulose. It has a similar life cycle but is composted after use life. These garments are compared with a standard t-shirt. The report also considers a slow-paced scenario in which a polyester garment passes between several owners and is regularly changed to maintain its appeal. It is updated with a transfer sublimation overprint three times, making the garment darker each time. Later it is joined with an outer shell of new material using laser technology to make a cropped, box-cut jacket.

The assessment was performed using environmental life cycle assessment. More particularly, the assessment was based on attributional process analysis with cutoff allocation procedures and comparison with a traditional reference garment life cycle. Key environmental effect categories considered here include climate change (greenhouse gas emissions), freshwater eutrophication, freshwater ecotoxicity and human toxicity (cancer and non-cancer).

The results indicate that the environmental outcomes of the paper-based garments can be competitive with the reference garment, particularly when the user is assumed to throw away a fully functional reference garment after five uses. This assumption may be true for some users, but the number of uses is considerably lower than the typical or the potential lifespan of the reference garment. The main factor assisting the paper-based garments is the reduction in the impacts per mass associated with material manufacturing (fibres, spinning, knitting), and also their lighter masses. Avoided impacts in the use phase play a secondary role on account of their location in Sweden with its low-carbon energy mix. The long-life garments are also competitive compared with their reference garments. This is primarily a consequence of how extending garment life avoids the production of new garments. The environmental impacts associated with transfer sublimation dye reprinting and laser processing do not significantly impact the overall environmental performance of the extended longlife garments, though confidentiality of data prevents a full assessment of these.

The garments in this report are pilot products and explorative scenarios rather than attempts to model existing business or behavioural patterns. The reader should therefore take care to keep the results in context when interpreting them. Nevertheless, the results suggest the value of pursuing the potential associated with these garment life cycles. We should also bear in mind that while the reference garments in this assessment are based on typical usage patterns, other more sustainable patterns are feasible.

This is to our knowledge the first ever corporate Planetary Boundaries analysis. It is an explorative collaboration between Houdini Sportswear, Albaeco and Mistra Future Fashion with the long-term ambition to create an open-source approach that will provide Houdini and other similar companies with a more holistic view on their sustainability efforts. Albaeco is closely tied to the Stockholm Resilience Centre (SRC), an international research centre for sustainability science at Stockholm University, known among other things for its work on planetary boundaries, resilience and ecosystem services.

This report aims to operationalize the Planetary Boundaries framework in a business context. The framework was established in 2009 when a group of scientists (Rockström and others, 2009) identified nine global environmental boundaries we should remain within so that our societies can continue to develop in a positive way. As such the Planetary Boundaries provide a holistic way of analysing sustainability that has acquired international recognition and contributed to the UN’s Sustainable Development Goals (SDGs). Rather than a narrow focus on for example water, chemicals or energy use, a planetary boundaries approach implies covering a larger set of critical environmental factors.

The manufacturing and consumption of clothes, like every other industry, plays a role in relation to all of the nine boundaries. For example, cotton is one of the most pesticide and water demanding crops grown; chemicals used when treating fabrics risk polluting water downstream from factories; and shell layer garments are often produced using compounds that stay in the environmental indefinitely and accumulate in the fatty tissues of wildlife and humans

Albaeco, Houdini and Mistra Future Fashion believe that analysing the textile industry from a Planetary Boundaries perspective is an important part of a larger ambition to integrate scientific analysis and resilience thinking into projects focused on accelerating business solution for sustainability.