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Densification through reduced residential space

Created on 16-10-2023

Design, planning and building
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Densification through reduced residential space poses a challenge in designing sustainable and affordable housing projects. This challenge takes different forms. For instance, at the neighbourhood or building block level, housing providers may request architects to maximize the number of units on a single piece of land, turning the design process into a trade-off between adequate housing space and the number of units. Another form of densification is at the unit design level, which involves reducing internal and external spaces by sacrificing balconies and squeezing spaces. This often leads to an uneven distribution of daylight and lack of good views between units, which could potentially affect the long-term health of the population.

Several motives may drive densification, including the need to reduce initial construction costs and overcome the continuing rise in construction prices. This challenge raises the question of what size is acceptable to ensure the presence of appropriate spaces that allow for adaptation. For example, when the family situation changes, such as having a new child, space for study, working from home, and hosting a relative in emergency situations. However, doesn't densification reduce the amount of materials used in construction and, therefore, make the project more environmentally friendly from a resource efficiency perspective?

Systems knowledge

Actors

Housing developers

Non-profit and for-profit housing organisations that undertake various tasks, such as the construction and management of housing.

Method

Interdisciplinary collaboration

Teams from different disciplines or fields work together to tackle complex problems, find innovative solutions and develop a broader understanding of a particular issue. This approach recognises that many real-world challenges cannot be adequately addressed within the confines of a single discipline or field.

Sustainability assessment systems

Frameworks, tools or methodologies used to assess and measure the sustainability performance of various entities, such as buildings, infrastructure projects, organisations and communities. These systems help assess and quantify environmental, social and economic impacts so that stakeholders can make informed decisions and improve sustainability practises.

Tools

Sustainability assessment systems

Frameworks, tools, or methodologies used to assess and measure the sustainability performance of various entities, such as buildings, infrastructure projects, organisations, and communities. These systems help assess and quantify environmental, social and economic impacts so stakeholders can make informed decisions and improve sustainability practices.

Target knowledge

Topic

Building regulations

A set of government-mandated standards, rules, and requirements that define how building and construction projects should be designed and executed.

Building sustainability

The practise of designing, constructing and operating buildings in a way that minimises their negative impact on the environment and promotes long-term environmental, social and economic sustainability.

Dimension

Environmental

This dimension focuses on understanding and addressing the environmental challenges and concerns related to human activities and their impact on the natural world.

Level

Building

The structure, project or development that is directly impacted by the various building regulations.

Transformation Knowledge

No references

Related cases

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Related vocabulary

Affordability

Sustainability

Life Cycle Costing

Area: Policy and financing

Housing is usually deemed unaffordable when it consumes more than a set percentage of a household's monthly income. The Eurostat[1] and the OECD[2]  follow this threshold approach and define households overburdened with housing costs as those spending more than 40% of their disposable income on housing. However, this indicator fails to capture financial hardship, particularly among lower-income households. In fact, lower-income households may be spending less than 40% of their income on housing and yet failing to meet adequate consumption levels for other goods. As a response, the residual income approach ascertains housing (un)affordability by defining a minimum level of consumption for a set of goods according to particular household types. The residual income approach builds on consumption data to define the minimum level of income necessary for a household to survive after housing costs. The main shortcoming of this approach is that relies on subjective measures of what constitutes the necessary minimal expenses for a household. These two definitions of affordability navigate two tensions 1) between housing and other types of consumption and 2) between the individual conceptions and what is affordable and what government considers to be affordable (Haffner & Hulse, 2021). More recently, scholars have emphasized the multi-faceted nature of affordability to include commuting and transport costs together with energy costs (Haffner & Boumeester, 2015). Other approaches focus on supply-side measures, for instance on the share of the housing stock that a household can afford (Chung et al., 2018). Evolutions in the measurement of affordability bear witness to the complexity of housing systems. Affordability is not only dependant on housing consumption but also housing supply, particularly in inelastic markets where providers have considerable power. At the same time, displacement pressures and rising energy costs in an older and inefficient stock add pressure on households to access affordable housing. References Chung C., Evangelou N., Geyer J., Quint R., Keith I., Coates D., Daula T., Frumkin S., Leventis A. v, Doerner W. M., Roderer D., & Barba M. (2018). A New Home Affordability Estimate: What Share of Housing Stock Can Families Afford?. FHFA Staff Working Papers 18-04, Federal Housing Finance Agency. Haffner M., & Boumeester, H. (2015). Housing affordability in the Netherlands: the impact of rent and energy costs. Journal of Housing and the Built Environment, 30(2), 293–312. https://doi.org/10.1007/s10901-014-9409-2 Haffner M., & Hulse K. (2021). A fresh look at contemporary perspectives on urban housing affordability. International Journal of Urban Sciences, 25(S1), 59–79. https://doi.org/10.1080/12265934.2019.1687320   [1] https://ec.europa.eu/eurostat/web/products-datasets/-/tessi165   [2] https://www.oecd-ilibrary.org/sites/624ee022-en/index.html?itemId=/content/component/624ee022-en#section-d1e6271  

Created on 15-07-2021

Author: A.Fernandez (ESR12), M.Haffner (Supervisor)

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Area: Community participation

To establish a definition of sustainability, what is first and foremost needed is to pinpoint the differences between two very similar terms: sustainability and sustainable development. While sustainability is the overall vision, sustainable development underlines the process of achieving it (Diesendorf, 2000). The UN has defined sustainable development as the effort to “meet the needs of the present without compromising the ability of future generations to meet their own needs” (WCED, 1987). While the 1987 definition is a highly generalised term, it has undoubtedly kickstarted several debates around relevant terminology. However, it still fails to profoundly address the multiplicity of factors and variables that come in play when talking about sustainable development (Mebratu, 1998); what and whose needs? How are these needs shaped and influenced by the nature-culture and local-global spectrums as well as the socio-political realities from which they emerged?   To tackle the first question, “what and whose needs” what is needed is simply to ask; participation and inclusion in decision-making have been identified as inherent values in empowering communities (Jenkins & Forsyth, 2010), while the equitable inclusion of communities in all facets of creation (concept, decision-making, construction) and post-creation (maintenance & management) can enhance “individual and social well-being” (Turner, 2000). Participation can therefore be a key element in “repairing the natural relationship between people and place” (Hamdi, 1995).   When it comes to understanding and situating those needs within the complex realities in which they occur, a crucial asset is empathy. Empathy signifies the ability to shift between perspectives and form emotional bonds while enhancing the cognitive capacity of processing the emotional state of the other. This “can bring significant advances to understanding sustainability challenges” (Brown et al., 2019).   Finally, to provide a more specific term for sustainable development, the 1987 UN term can be rephrased as not only the effort to meet one’s needs of the present without compromising the ability of future generations to do the same, but also the effort to identify, understand and contextualise those needs, connect and empathise with the people voicing them, and ultimately challenge the status quo, whenever needed ”.     Effrosyni Roussou - DRAFT     Reference List:   Brown, K. et al. (2019) Empathy, place and identity interactions for sustainability, Global Environmental Change, 56, pp. 11-17   Diesendorf, M. (2000), ‘Sustainability and sustainable development’, in Dunphy, D. Benveniste, J. Griffiths, A. and Sutton, P. (eds.) Sustainability: The corporate challenge of the 21st century, Sydney:  Allen & Unwin, pp. 19-37   Hamdi, N. (1995) Housing without Houses: Participation, Flexibility, Enablement Warwickshire: Practical Action Publishing   Jenkins, P., Forsyth, L. (eds.). (2010) Architecture, Participation and Society. New York: Routledge   Mebratu, D. (1998) ‘Sustainability and sustainable development: Historical and conceptual review’, Environmental Impact Assessment Review, 18(6), pp. 493–520   Turner, J.F.C. (2000) Housing by People: Towards autonomy in building environments. London: Marion Boyars Publishers Ltd   World Commission on Environment and Development. (1987). Our common future. Oxford: Oxford University Press

Created on 08-09-2021

Author: E.Roussou (ESR9)

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Area: Design, planning and building

Life Cycle Costing (LCC) is a method used to estimate the overall cost of a building during its different life cycle stages, whether from cradle to grave or within a predetermined timeframe (Nucci et al., 2016; Wouterszoon Jansen et al., 2020). The Standardised Method of Life Cycle Costing (SMLCC) identifies LCC in line with the International Standard ISO 15686-5:2008 as "Methodology for the systematic economic evaluation of life cycle costs over a period of analysis, as defined in the agreed scope." (RICS, 2016). This evaluation can provide a useful breakdown of all costs associated with designing, constructing, operating, maintaining and disposing of this building (Dwaikat & Ali, 2018). Life cycle costs of an asset can be divided into two categories: (1) Initial costs, which are all the costs incurred before the occupation of the house, such as capital investment costs, purchase costs, and construction and installation costs (Goh & Sun, 2016; Kubba, 2010); (2) Future costs, which are those that occur after the occupancy phase of the dwelling. The future costs may involve operational costs, maintenance, occupancy and capital replacement (RICS, 2016). They may also include financing, resale, salvage, and end-of-life costs (Karatas & El-Rayes, 2014; Kubba, 2010; Rad et al., 2021). The costs to be included in a LCC analysis vary depending on its objective, scope and time period. Both the LCC objective and scope also determine whether the assessment will be conducted for the whole building, or for a certain building component or equipment (Liu & Qian, 2019; RICS, 2016). When LCC combines initial and future costs, it needs to consider the time value of money (Islam et al., 2015; Korpi & Ala-Risku, 2008). To do so, future costs need to be discounted to present value using what is known as "Discount Rate" (Islam et al., 2015; Korpi & Ala-Risku, 2008). LCC responds to the needs of the Architectural Engineering Construction (AEC) industry to recognise that value on the long term, as opposed to initial price, should be the focus of project financial assessments (Higham et al., 2015). LCC can be seen as a suitable management method to assess costs and available resources for housing projects, regardless of whether they are new or already exist. LCC looks beyond initial capital investment as it takes future operating and maintenance costs into account (Goh & Sun, 2016). Operating an asset over a 30-year lifespan could cost up to four times as much as the initial design and construction costs (Zanni et al., 2019). The costs associated with energy consumption often represent a large proportion of a building’s life cycle costs. For instance, the cumulative value of utility bills is almost half of the cost of a total building life cycle over a 50-year period in some countries (Ahmad & Thaheem, 2018; Inchauste et al., 2018). Prioritising initial cost reduction when selecting a design alternative, regardless of future costs, may not lead to an economically efficient building in the long run (Rad et al., 2021). LCC is a valuable appraising technique for an existing building to predict and assess "whether a project meets the client's performance requirements" (ISO, 2008). Similarly, during the design stages, LCC analysis can be applied to predict the long-term cost performance of a new building or a refurbishing project (Islam et al., 2015; RICS, 2016). Conducting LCC supports the decision-making in the design development stages has a number of benefits (Kubba, 2010). Decisions on building programme requirements, specifications, and systems can affect up to 80% of its environmental performance and operating costs (Bogenstätter, 2000; Goh & Sun, 2016). The absence of comprehensive information about the building's operational performance may result in uninformed decision-making that impacts its life cycle costs and future performance (Alsaadani & Bleil De Souza, 2018; Zanni et al., 2019). LCC can improve the selection of materials in order to reduce negative environmental impact and positively contribute to resourcing efficiency (Rad et al., 2021; Wouterszoon Jansen et al., 2020), in particular when combined with Life Cycle Assessment (LCA). LCA is concerned with the environmental aspects and impacts and the use of resources throughout a product's life cycle (ISO, 2006). Together, LCC and LCA contribute to adopt more comprehensive decisions to promote the sustainability of buildings (Kim, 2014). Therefore, both are part of the requirements of some green building certificates, such as LEED (Hajare & Elwakil, 2020).     LCC can be used to compare design, material, and/or equipment alternatives to find economically compelling solutions that respond to building performance goals, such as maximising human comfort and enhancing energy efficiency (Karatas & El-Rayes, 2014; Rad et al., 2021). Such solutions may have high initial costs but would decrease recurring future cost obligations by selecting the alternative that maximises net savings (Atmaca, 2016; Kubba, 2010; Zanni et al., 2019). LCC is particularly relevant for decisions on energy efficiency measures investments for both new buildings and building retrofitting. Such investments have been argued to be a dominant factor in lowering a building's life cycle cost (Fantozzi et al., 2019; Kazem et al., 2021). The financial effectiveness of such measures on decreasing energy-related operating costs, can be investigated using LCC analysis to compare air-condition systems, glazing options, etc. (Aktacir et al., 2006; Rad et al., 2021). Thus, LCC can be seen as a risk mitigation strategy for owners and occupants to overcome challenges associated with increasing energy prices (Kubba, 2010). The price of investing in energy-efficient measures increase over time. Therefore, LCC has the potential to significantly contribute to tackling housing affordability issues by not only making design decisions based on the building's initial costs but also its impact on future costs – for example energy bills - that will be paid by occupants (Cambier et al., 2021). The input data for a LCC analysis are useful for stakeholders involved in procurement and tendering processes as well as the long-term management of built assets (Korpi & Ala-Risku, 2008). Depending on the LCC scope, these data are extracted from information on installation, operating and maintenance costs and schedules as well as the life cycle performance and the quantity of materials, components and systems, (Goh & Sun, 2016) These information is then translated into cost data along with each element life expectancy in a typical life cycle cost plan (ISO, 2008). Such a process assists the procurement decisions whether for buildings, materials, or systems and/or hiring contractors and labour, in addition to supporting future decisions when needed (RICS, 2016). All this information can be organised using Building Information Modelling (BIM) technology (Kim, 2014; RICS, 2016). BIM is used to organise and structure building information in a digital model. In some countries, it has become mandatory that any procured project by a public sector be delivered in a BIM model to make informed decisions about that project (Government, 2012). Thus, conducting LCC aligns with the adoption purposes of BIM to facilitate the communication and  transfer of building information and data among various stakeholders (Juan & Hsing, 2017; Marzouk et al., 2018). However, conducting LCC is still challenging and not widely adopted in practice. The reliability and various formats of building related-data are some of the main barriers hindering the adoption of LCCs (Goh & Sun, 2016; Islam et al., 2015; Kehily & Underwood, 2017; Zanni et al., 2019).

Created on 05-12-2022

Author: A.Elghandour (ESR4)

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A Turning Point Conversation on Portuguese Public Dwellings Design, Is it some kind of Feminism?

Posted on 06-09-2022

You know those kinds of conversations that are filled with enthusiasm and passion. It's one of those moments that proves to you: yes! Passion exists and it works!   This time it was passion for design as a tool to indirectly empower people and their sense of belonging. It's about promoting social justice!   Currently in Lisbon, there are several affordable rent programmes "Programa de Renda Acessível" (PRA) run by the City Council in view of the high rent prices in the city. Some programmes are public-private partnerships like this initiative. Other programmes are purely public investments from start to finish, where people can apply for rental housing through this website, for example.   My co-supervisor Dr Vasco Moreira Rato from ISCTE - where I had my secondment - is also chief advisor to Lisbon City Councillor on Housing and Public Works, Filipa Roseta. Dealing at the front line with housing issues, the discussions with him were very informative, practical and honest, both from the research and the authorities' point of view. In the process, he wanted to show me an example of how parametric design can benefit public housing in the context of affordability to determine the suitable design parameters within a certain budget while responding to various requirements.       And here comes one of those memorable and inspiring conversations as a Marie Curie ESR.   I had a fruitful conversation with the architects Susana Rato and Joana Couto from SRU (Sociedade de Reabilitação Urbana). They were responsible for preparing the Public Housing concept design for low-cost housing projects that are fully financed by the public sector.  They explained what, why and how they created this schematic design to achieve ambitious design goals within a certain given construction budget. They had a limited budget of about 1000 euros per square metre for construction. Thus, they exploited the power of geometric parametrisation to determine appropriate modern design parameters while meeting the various requirements such as space ratios, areas, technical requirements and regulations.       It is interesting to note that one of the main objectives of this schematic design process is to ensure that future residents feel comfortable where they live and to support their right to live in affordable, durable and beautiful homes.   How did they do so?   They ensured that the spatial needs of different family structures were accommodated by adhering to Portuguese building codes and regulations. As two Portuguese ladies, they questioned the design as if this house would be their own house, that of their relatives or the future home of their children. They insisted on providing terraces for each living unit as an extension of the house to connect the residents with nature, which benefits their soul and mind. They also know that Portuguese people love being outside. Various services have also been proposed, such as a shared laundry room and a communal room. For buildings in neighbourhoods where there are no kindergartens, a kindergarten on the ground floor was proposed.   They worked with energy specialists to design energy-efficient building envelopes, define the technical requirements for walls, doors and windows, and decide on the appropriate renewable energy and water heating techniques. In addition, the distribution of daylight in the interior spaces was investigated. A construction economist accompanied all steps of their design journey, simultaneously calculating construction costs and investigating economic feasibility to modify the design accordingly without compromising the quality and performance requirements of the residential building. This hard work does not negate the fact that they were unable to work with the community itself during the design process due to the tight timeframe of the project. This reflects the reality of many architects in practise. They also expressed their interest in using the possibilities of Building Information Modelling (BIM) in the future, as it would have saved them a lot of time in working with other disciplines to complete this project. It would also be an important tool for management and cost control during construction.       When I returned to Sheffield and while attending Doina Petrescu class on feminism research as part of my PhD training.   I immediately remembered Susana and Joana! Now I see their work and enthusiasm as a kind of feminist action – consistent, practical and balanced - advocating the public housing residents' rights and doing the best in the area under their control. I cannot deny that it was admirable and inspirable.       To sum up!   This conversation triggered the turning point of my PhD research. Currently, I am passionately investigating literature to answer how to design a house that promotes household health and wellbeing?   But, Why?   I dream of Affordable Happy Healthy Housing [Why not?]. Can you label a house as sustainable if it is negatively impacting your physical and mental health?   Hmmm, nope. But in reality, it does not sound that simple …   Sim Senhor [Yes Sir in Portuguese] and that is what we are here to contribute to ? See you in the next blog post! Goodbye!       Relevant Sources https://www.lisboaocidentalsru.pt/ https://www.lisboa.pt/atualidade/noticias/detalhe/camara-constroi-476-casas-destinadas-ao-programa-de-renda-acessivel https://www.publico.pt/2019/12/04/local/noticia/lancado-concurso-construcao-renda-acessivel-entrecampos-1896237

Author: A.Elghandour (ESR4)

Secondments

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