Historic buildings and refurbishment.

This article forms part of a legacy document containing short overviews written by the forum leaders of 31 different topics which took place during PLEA 2017. This article is from Forum 13, Historic and Vernacular Buildings and examines the topic of historic building and refurbishment. The majority of the buildings that will exist in 2050 are already built. The greatest challenge we face today is to ensure that these buildings are brought up to a standard that can not only ensure they continue to provide safety and comfort of their occupants over time but also that the energy used to do so does not have too great an impact on our climate and environment

The UK's experience in mitigating climate change: a planned strategy or a learning curve?

Reducing the CO2 emission by 80% from 1990 level by 2050 is a challenging operation for the UK. This challenge has embarked the whole nation in a national exercise that involves professionals in all sectors, corporations, SMEs, families and individuals. The nation meets every day with new tasks, initiatives and incentives designed to meet that target. The built environment is one aspect of this multi-faceted exercise and within the built environment itself many aspects are being tackled. This paper evaluates the current legislations, initiatives and incentives introduced in the UK to reduce the energy demand in the Built Environment and how they contribute to meeting the UK's international obligation in cutting CO2 emission. Incentives such as feeding tariff for renewable energy, Green Deal for upgrading buildings and many other initiatives; have been withdrawn, revised or replaced after their excessive success or unexpected failure. These actions reflect the lack of clear plan and strategy. This paper won't examine the reasons of these success or failures but will use these disruptions as a call for the establishment of serious tools and mechanisms as a platform for discussion in mitigating climate change. Although the theme of this conference is dedicated to developing world, we believe that exchanging our experiences will benefit developing countries in avoiding our mistakes and follow successful steps. There is certainly no benefit in re-experiencing same failures as the world is embarked in the same climate change mitigating exercise

Multi-criteria evaluation of renewable energy alternatives for electricity generation in a residential building.

The residential sector is well known to be one of the main energy consumers worldwide. The purpose of this study is to select the best renewable energy alternatives for electricity generation in a residential building by using a new integrated fuzzy multi-criteria group decision-making method. In renewable energy decision-making problems, the preferences of experts and decision-makers are generally uncertain. Furthermore, it is challenging to quantify the reel performance of renewable energy alternatives using a set of exact values. Fuzzy logic is commonly applied to deal with those uncertainties. The method proposed in this paper combines different methods. First, the Delphi method is used in order to select a preliminary set of renewable energy alternatives for electricity generation as well as a preliminary set of criteria (economic, environmental, social, etc.). Then, the questionnaire is used to study the renewable energy alternatives preferences of the residents of the residential building’. Later, the FAHP (Fuzzy Analytical Hierarchy Process) is implemented to obtain the weighs of the criteria taking into consideration uncertainties in expert's judgments. Finally, the FPROMETHEE (Fuzzy Preference Ranking Organization Method for Enrichment Evaluation) global ranking is performed in order to get a complete ranking of the renewable energy alternatives taking into account uncertainties related to the alternatives' evaluations. The originality of this paper comes from the application of the proposed integrated Delphi- FAHP- FPROMETHEE methodology for the selection of the best renewable energy alternatives for electricity generation in a residential building. A case study has validated the effectiveness and the applicability of the proposed method. The results reveal that the proposed integrated method helps to formulate the problem and is particularly effective in handling uncertain data. It facilitates the selection of the best renewable energy alternatives in a manner that is participatory, comprehensive, robust, and reliable

Energy efficient homes: implementation of renewable energies in retrofitted buildings.

According to the Climate change (Scotland) Act 2009, by 2020 total carbon emission should be reduced 42% respect 1990 levels (and 80% lower than the baseline by 2050). In this context, it is important to highlight that buildings are responsible of 45% of total CO2 emissions (RAENG 2010) and just residential buildings represent 26% of UK CO2 emissions (Moran, Nikolopoulou and Natarajan 20212). Moreover, due to the low average renovation rate in Europe, 1.2-1.4% per year (Dyrbøl, Thomsen, et al. 2010), it is estimated that between 80% (RAENG 2010) AND 85% (Palmer et al. 2006) of the buildings we will occupy by 2050 are already built. Consequently, energy efficiency could be achieved working on the equipments substitution and improving the factors that affect the demand. To achieve the low energy demand rates of new buildings in retrofitted properties is almost impossible. However, combination of energy demand reduction measures and use of renewable energies could lead to a high efficient homes with low rates of fuel consumption and thus low greenhouse gases emissions

Decision making criteria in adopting renewable energies in the built environment.

The best system for a particular property is strongly linked to the occupiers. User’s energy needs vary depending on type and size of building they occupy. A deeper analysis of the heating and electricity demand should include detailed assessment of activities carried out in the building. Physical constraints due to the site’s characteristics will determine the viability of the different technologies. A complete assessment will require a detailed evaluation of location and orientation of the buildings and the potential obstacles that might reduce the solar radiation or wind speed. The assessment should also include the evaluation of the visual, sound and environmental impact. The chosen solution should be compatible with the building typology, structure, fabric and type of roof. Moreover, some microgeneration technologies can work well even if a property has relatively low insulation and air tightness levels while others will not. When installing new systems in existing buildings, care must be taken to avoid damage or excessive loss particularly where the materials are fragile. The financial viability of a renewable energy system depend not only on the efficiency of the technology, but also on the available budget, the maintenance costs or the estimated lifespan. To evaluate the effectiveness of any system would be necessary to include both the grants funding and the feed-in tariff available for each system

Visual documentation process of historic building refurbishment: improving energy efficiency by insulating wall cavity.

The North East of Scotland's construction method is similar to most popular building typologies in the UK. This typology can vary in term of external material (Granite, brick or stone) but with a secondary, usually timber sub frame with a lining on its interior. Insulation was seldom a consideration when such buildings were completed. Statistics shows that 80% of existing buildings in the UK will need to be upgraded. The lack of knowledge in dealing with old building fabric's manipulation has a negative impact on buildings' integrity. The documentation of such process seems to be an important step that buildings' actors should undertake to communicate a practical knowledge that is still at incubation stage. We wanted for this documentation to be visual, as descriptions might mislead none specialised and specialised in the field due to the innovative approach our method was conducted with. For the Scottish context this research/experiment will concentrate on existing granite wall buildings with plastered lath internal wall. It is unfortunate to see the commonly beautiful interiors of Scottish buildings disappearing, when the internal linings are removed. Skips are filled with old Plaster and Lath and new linings have to be supplied and fitted. Excessive waste is created in this change. This paper is based on a historic building energy improvement case study financed by the European commission and the Scottish Government. The pilot study consists of insulating an 18th century house using an innovative product and method. The project was a response to a call by the CIC start (Construction Innovation Club), aiming to establish a link between SMEs and the Universities. The project saw the day in collaboration with Icynene Canada, KDL Kishorn (see full list in the acknowledgment). This paper describes the process through which the team went through to improve the building envelope without damaging the buildings original features (Loveday et all). The energy efficiency improvement consists on improving the walls U-val by introducing an insulation material Icynene (Sadineni, France & Boehm 2011) into the cavity wall. The U-val was improved by 50% and no redecoration was needed after the operation and no disturbance to the building's occupants

Barriers to the adoption of energy efficiency measures in Mostaganem, Algeria.

The residential sector of Algeria consumes 29% of the total energy consumption. In order to reduce and address this consumption along with the challenges of climate change, the Algerian public policy considers energy efficiency investment measures (EEIMs) in the residential sector as a key factor. However, despite the recommendations and incitement measures from the government, the adoption of EEIMs of Algerian homeowners is too low. In 2018, EEIMs have been implemented in 4,000 houses. This number represents only 4% of the government's target which is the implementation of EEIMs in 100,000 houses per year. The present article, accordingly, attempts to explore the barriers to the adoption of EEIMs. To this effect, a questionnaire survey with 150 randomly selected Algerian single-family homeowners in Mostaganem area was used for the study. It was found that the five greatest barriers to the adoption of EEIMs were: (1) the lack of subsidies and rebates on energy efficient equipment, (2) the high initial prices of energy efficient equipment, (3) the lack of techniques and tools for the estimation of saved energy, (4) the unwillingness to borrow money and (5) the difficulty of identifying, procuring, installing, operating and maintaining energy efficiency measures. The principal component analysis categorised 16 barriers around four components: (1) “Financial” barriers, (2) “Technological” barriers, (3) “Lack of time and knowledge” barriers and (4) “Attitude towards energy efficiency improvements” barriers. Finally, the multivariate analysis of variance (MANOVA) analysis has shown that the perception of barriers to the adoption of EEIMs also differs in accordance with certain personal characteristics of the homeowner

Technology and innovation in adapting architectonic tradition aiming for a sustainable future in the Middle East.

With relation to the communities' shift in the ME from being mainly concerned of adapting and maintaining quality of life correlated with ATA, towards global trends adaptation, the presence of ATA has been a significant feature in private and public buildings. This investigation will highlight the socio-psychological, physical and behavioral effects that have emerged as builders seek to better contemporary living standards. The indicated paradigm will impact the well-being of individuals, while they remain attached to their culture. In Dr. Gerda's Thesis (2000), she stated that a place attachment is a valuable element that has an impact on the society and the individual, attributing to their development form an essential relationship. Another trigger is how traditional features of buildings adapted to technology, can be described as better living standards in indoor environments. Aforementioned collaboration will require a consideration of functional parameters. The research will accumulate daylighting performance in relation to ATA through the level of comfort, privacy, and technology. Bennadji (2003), implies that the effect of the amount of daylight on sociocultural needs of the habitant is worth noting. This exploration will emphasis the consideration of occupants and their social needs, and human emotions; Alkahlidi (2012), states that traditional architecture in the Arab World represents a living witness for the perseverance of this architecture to the local environment

Existing housing stock in the UK and the thermal insulation challenge: case of granite traditional constructions in the United Kingdom.

The increase in energy price has sparked a debate in the UK as to what would be the best way to address this problem. Various political parties and civil societies are also concerned and various responses to the crisis are being suggested and debated. The British Prime Minister; after a long debate about waiving the tax related to the cost of energy; gave a straightforward and radical answer. It was suggested that the existing building stock should be improved to reach a certain standard. The goal is to reduce the energy consumption which will ensure a reduction in the running cost of household and commercial assets in the UK. The government initiative was to make grants available to dwellings that shows a lack of energy efficiency this includes the increase of insulation of the buildings' envelop as well as renewable energy generator and end use equipments. The CO2 emissions per capita and the reduction of the national dependency of finite fossil fuel resources are achievable via major refurbishment programmes of both owners occupied and rented properties. Many of the easy measures have been done, leaving only the major areas that need addressing. These areas are complex and expensive therefore home owners and private landlords are deterred from addressing them. Incremental improvements are no longer cost or physically effective, however; therefore a holistic and integrated approach to buildings' refurbishment is required. The aim of this research is to present the different possible scenarios of refurbishment based on the most popular building typologies in the UK, focusing on typical case studies in Aberdeen as exemplars

Investigating the major causes of morphological transformations in the CBD of Accra and the impact on urban heat island intensity.

Tropical urban sites are constantly under the threats of the adverse effects of urban heat island (UHI) - a situation which is aggravated by climate change. Urban morphology comprises a large set of factors that play an important role in modifying urban climate and, consequently, the potential energy demand and supply in cities. Ghana has since independence, experienced a rapid population growth, which has resulted in the urbanisation of many of its towns. The influx of people into the urban areas means there is a high demand for more housing, commercial and other infrastructural developments. For Accra however, this drive has resulted in drastic reduction in urban greenery. The aim of this study is to investigate the main causes of morphological transformations that have occurred in Accra over the past few decades, with the view to identifying possible measures for UHI mitigation. This study employs a mixed-methods research approach. First, to gain an in-depth understanding of the underlying causes of the morphological transformation the city has undergone, qualitative data are gathered through desktop studies and face-to-face semi-structured interviews with some experienced Ghanaian built environment professionals. The quantitative study involves the collection of weather data from selected monitoring points in the city. Upon analysing the qualitative data, other major causes of the morphological transformations that have emerged include poor enforcement of development control, non-adherence to building regulations; inadequacies in the existing building regulations; architects and building designers lacking the motivation for sustainable design etc. It is evident that areas with large expanse of hardscapes and significantly reduced greenery are experiencing high UHI intensities. Recommendations include measures which address the identified challenges as well as urban regeneration