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The possibility of producing binderless panels made of milled coconut husk, a largely available by-product of the coconut oil industry, has been shown in previous researches. Long pressing times and a high risk of blisters have however hindered the industrial implementation of the process. In this study, a more energy-efficient manufacturing process, involving a tailored degassing step, was developed on a laboratory scale and then validated at an industrial size (2 × 1 m2). To achieve mechanical properties close to the European and Japanese standards for fibreboards and to avoid the delamination of the boards, final densities between 900 and 1000 kg m−3 had to be targeted. Similarly, a successful board production was only possible if the moisture content of the husk was between 10 and 25%. The need for a suitable mat-forming technology to avoid the risk of warping of the panel was highlighted.

Purpose The environmental impact of the social building stock is relevant, particularly in emerging economies. Life cycle thinking is not yet established, however. Locally available, alternative building concepts could potentially reduce the environmental impact of the construction segment. This paper examines the environmental performance of Bas-built low-cost housing for an example of the Philippines, and the potential to reduce its environmental impact through use of three alternative building technologies: cement–bamboo frames, soil–cement blocks, and coconut board-based housing. Methods Life cycle assessment models are implemented and evaluated with software SimaPro, using the single-impact indicators global warming potential (GWP) and cumulative energy demand (CED) and the multi-impact indicator Impact2002+. According to EN 15978, the life cycle phase product and construction process (A), use stage (B), end-of-life (C) and supplementary information beyond the building life cycle (D) have been assessed. Theoretically calculated inflows from standard construction procedures used in phase A have been verified with 3 years of empirical data from implemented construction projects. For phases B, C and D, attention was given to service life, use-phase, allocation of waste products, biogenic carbon and land-use assumptions. Scenarios reflect the actual situation in the emerging economy. Processes, such as heat recovery from thermal utilization, which are not existing nor near to implementation, were excluded. Results and discussion For an assessment of the phases A–B–C–D with GWP, a 35% reduction of environmental impact for soil–cement blocks, 74%for cement–bamboo frame, and 83% for coconut board-based houses is obtained relative to a concrete reference house. In absolute terms, this relates to a reduction of 4.4, 9.3, and 10.3 t CO2 equivalents over a service life of 25 years. CED showed higher impacts for the biogenic construction methods coconut board and cement–bamboo frames of +8.0 and +4.7%, while the soil–cement technology was evaluated −7.1% compared to GWP. Sixteen of 17 midpoint categories of Impact2002+ confirmed an overall reduction potential of the alternative building methods, with the midpoint category land occupation being the exception rating the conventional practice over the alternatives. Conclusions It is concluded that the alternative construction technologies have substantial potential to reduce the environmental burden caused by the social housing sector. The service life of the alternative technologies plays a vital role for it. LCA for emerging economies needs to incorporate realistic scenarios applicable at their current state or belonging to the most probable alternatives to ensure valuable results. Recommendations for further research are provided.

The common testing protocol to determine the shear strength of bamboo parallel to grain is ISO 22157. However, widely documented limitations of this test procedure calls for an alternative testing protocol. This study compared ISO 22157 (TP1) and 2 alternative testing protocols proposed by Base Bahay (TP2a and 2b) in determining shear strength of bamboo parallel to grain. The study used a local bamboo known as “kawayang tinik” (Bambusa blumeana). Results showed that TP1 produced more pure shear failures at 65% compared to TP2a and TP2b at 55% each. Shear strength values between the three methods were not significantly different, although, TP2b resulted in the lowest coefficient of variation at 18%. Also, TP2b was found to be the most effective in terms of specimen preparation, ease of assembly of testing equipment, and low variability in data.

The use of cellulosic materials in the construction of low-rise housing in tropical climates has great potential. Bambusa blumeana (B. blumeana, J.A. and J.H. Schultes), the most abundantly available bamboo species in the Philippines, is a promising alternative material for the construction of cost-efficient buildings. However, to comply with municipal rules and regulations for construction, a comprehensive understanding of the organic raw material is needed to permit its application as a load-bearing structural member. In this study, the physical and mechanical properties of B. blumeana bamboo from a typical growth region of the Philippines were tested according to ISO 22157-1 (2004) and ISO 22157-2 (2004). The characteristic strength values of B. blumeana were as follows: compressive and tensile strengths parallel to the grain of 20 and 95 MPa, respectively; shear strength of 5 MPa, bending strength of 34.6 MPa, and the mean and fifth percentile modulus of elasticity of 13100 and 8600 MPa, respectively. Based on these results, a recommendation for permissible stresses for structural design was made in line with ISO 22156 (2004).

International bodies such as the Intergovernmental Panel on Climate Change or the United Nations agree in seeing the built environment as one of the key sectors to mitigate emissions. Cost abatement curves as generated by McKinsey list a number of technologies in the building sector, which are already cost effective and are together potentially allowing for carbon mitigations of 2,0-3,0 Gtons of CO2eq per annum. Despite being economically attractive as well as desirable from a climate change mitigation viewpoint, almost none of these technologies are massively upscaling. The European Union requires the individual member countries to implement measures to speed up energy efficiency in the building sector. Each country however is free on the exact way how to do so as long as its specific approach is in line with the general EU road-map. This paper assesses the effect of the implemented frameworks for France and Germany and draws conclusions regarding immediate and future phenomenon. Findings are that both countries have implemented holistic frameworks that include legal standards, financial incentives and market education. While the German setup focuses on systemic solutions though, France promotes a component based subsidy scheme. In both countries the refurbishment rate on a component level is substantially higher than for deep renovation with window exchange and roof refurbishment being the most commonly implemented ones. Component based measures are higher in France than in Germany, in some cases even meeting the aimed for 3% needed for a refurbishment of the complete building stock by 2050 on an EU level. In general however both countries fail to achieve refurbishment and renovation rates that enable them to stand up to the EU 2050 targets yet, indicating that the market barrier and mechanisms have to be monitored and understood better to implement massive up-scaling of energy efficient technologies.

This paper highlights the need for a more inclusive and sustainable development of social housing in rapidly developing countries of Asia, Latin America, and Africa. At the example of the Philippines, a multi-perspective development process for a bamboo-based building system is developed. Sustainability Assessment Criteria are defined through literature review, field observations and interviews with three stakeholder clusters: (1) Builders and users of traditional bamboo houses in the Philippines; (2) Stakeholders involved in using forest products for housing in other countries around the world; and (3) Stakeholders in the field of social housing in the Philippines. Through coding and sorting of data in a qualitative content analysis, 15 sustainability assessment criteria are identified clustered into the dimensions society, ecology, economy, governance, and technology. Guided by the sustainability criteria and four implementation strategies: (A) Research about and (B) Implementation of the building technology; (C) Participation and Capacity Building of Stakeholders; and (D) Sustainable Supply Chains, a strategic roadmap was created naming, in total, 28 action items. Through segmentation of the complex problem into these action items, the paper identifies one-dimensional methods leading to measurable, quantitative endpoints. In this way, qualitative stakeholder data is translated into quantitative methods, forming a pathway for a holistic assessment of the building technologies. A mid-point, multi-criteria, or pareto decision-making method comparing the 28 endpoints of the alternative to currently practiced conventional solutions is suggested as subject for further research. This framework paper is a contribution to how sustainable building practices can become more inclusive, incorporating the building stock of low-income dwellers. It bridges the gap between theoretical approach and practical applications of sustainability and underlines the strength of combining multi-dimensional development with stakeholder participation.