Poorang Piroozfar

An Investigation into GHG and non-GHG Impacts of Double Skin Façades in Office Refurbishments

The building sector is a major contributor to energy consumption, greenhouse gas (GHG) emissions, and depletion of natural resources. In developed countries, existing buildings represent the majority of the stock, their low‐carbon refurbishment hence being one of the most sensible ways to mitigate GHG emissions and reduce environmental impacts of the construction sector. This article has investigated and established the GHG and non‐GHG life cycle impacts of several double skin facade (DSF) configurations for office refurbishments by means of a parametric comparative life cycle assessment against up‐to‐standard single skin facade (SSF) refurbishment solutions. Two different methods were used to assess both GHG emissions and other environmental impacts. Results show that if, on the one hand, most of the DSF configurations assessed actually reduce GHG emissions compared to SSFs over their life cycle — thus supporting a wider adoption of DSFs for low‐carbon refurbishments — on the other hand, there exist non‐negligible ecological and environmental impacts that the DSF generates, specifically in terms of some materials of the structure and their final disposal. Research attention is thus needed regarding the environmental impacts of the materials used for DSFs and not only in minimizing the energy consumption of the operational phase.

The impact of design decisions on post occupancy processes in school buildings

Purpose – This paper aims to review the impact of design and specification decisions for major works during post‐occupancy processes; the routine maintenance and management of school premises. It also seeks to explore the relationship between the main stakeholders and how this impacts decision‐making and the post‐occupancy operation of school buildings.Design/methodology/approach – In addition to a literature review, qualitative data were also obtained through a focus group; a steering group. The steering group consisted of stakeholders tasked with delivering and managing school premises in the Sussex County.Findings – The findings contribute to understanding the impact of design decisions on post‐occupancy processes in schools. A basic model is also presented as a guide for requirements and decision mapping in post‐occupancy design decision processes in schools.Research limitations/implications – The study was conducted with the participation of a representative sample of stakeholders. There may be the n...

Evolution of Nontraditional Methods of Construction: 21st Century Pragmatic Viewpoint

AbstractTechnology has played a major role in the process of forming the architectural theory and practice during the twentieth century. The discourse on technology is well received both in hermeneutics and in architectural theory. What has been paid very little attention is how the notion has evolved and developed pragmatically. This paper will focus on the paradigm shift from the established ways of building on-site to the new methods of production of space off-site. The focus, however, is not the shift itself but rather how the destination paradigm has been comprehended and translated into practical solutions and how those solutions have established a dialogue with architecture both as a profession and as the final product. The milestone in this study is the Industrial Revolution, known as the architect of change in this transition. This paper does not provide a chronology of construction technology. By contrast, it focuses on the evolution both of the concepts from a semantic viewpoint and of the appl...

A co-creation platform for post-occupancy decision support

Purpose – The purpose of this paper is to report on partial findings of a research project on post‐occupancy design in school projects. It provides a brief review of key factors, and major players in post‐occupancy processes.Design/methodology/approach – Subsequent to literature review for the research, the primary data was obtained from a steering group (stakeholder forum) comprising of a sample of primary and secondary school representatives, local authorities and building professionals. Following the data collection, visits were arranged to the selected schools, and local councils and semi‐structured interviews with school and council authorities were carried out. At the same time, research meeting and directed studies were held to best explore the applications for devising the toolkit. Simulated and real cases for making decisions in post‐occupancy design were selected to devise a model‐base to test out the applicability of the devised prototype of the toolkit.Findings – This study provided clarificat...

Integrated Façade System for Office Buildings in Hot and Arid Climates: A Comparative Analysis

High solar gain in hot and arid climates causes overheating in summer and increases the demand for air conditioning, energy and carbon footprints of buildings. There are different strategies, tools and solutions to address this problem, but Integrated Facade Systems (IFSs)—facade systems where different technological solutions are integrated to improve performance and to lower the impact of the building—are still an underdeveloped yet a fast-growing field of research. Such systems can reduce solar heat gain, lower air conditioning costs and lessen glare, while maximising the use of natural light and help produce energy if combined with PV technology. Previous research has addressed one or a combination of some of the influential factors on performance of such systems, yet there still is a gap in the state-of-the-art research in comprehensive systematic approach not only to help gauge the impact of alteration of parameters on the IFS performance, but also an approach which can be deployed in other studies where the focus is on facade systems. With a special reference to office buildings in hot and arid climates, this chapter sets out to systematically identify IFS parameters which have potential impacts on energy, lighting, glare and heat gain. Then as a part of a comprehensive ongoing research in this area, this chapter presents a proof of concept to demonstrate the application of such methodology to a parametric study of IFS technology. In doing so, it chooses only one of the parameters indicated in this systematic review and uses building simulation as its core method to investigate the influence and impacts of those variations on performance of IFS. It will indicate how this approach provides high flexibility to adjust or configure any combination of those parameters and to measure, subjectively, how this will result in change in facade performance.

Life cycle assessment of domestic hot water systems: a comparative analysis

On average, hot water is responsible for 18% of residential energy consumption and corresponding greenhouse gas (GHG) emissions. Several domestic hot water systems (DHWSs) are commonly used but their life cycle impacts are yet to be established comprehensively. This is due to those impacts varying significantly within the context and the system boundaries of the assessment. This article reports findings from a comparative cradle-to-grave life cycle assessment (LCA) of five DHWSs in the UK context. Primary data acquired from a case study contributed to achieving accurate life cycle inventories that were then modelled in SimaPro through the ecoinvent database. Global Warming Potential (GWP) is the impact assessment method used. Amongst the five types, solar heater with electric backup appears to be the least damaging alternative. The study also reinforces the importance of adopting a cradle-to-grave approach if LCA results are to accurately reflect environmental impacts holistically and lead to better, more informed decisions.

Visual perception and the choice of systemised building façades

Prefabricated building systems can offer benefits in many different respects, including but not limited to cost control of a project. However, there are also some restrictions that, if not understood properly and adopted accordingly, may have some adverse effects on design, construction and post-occupancy stages of buildings. As limited as any system is in replicating complex forms, they may still be utilised depending on many factors. Briefly drawing upon key theories of perception such as Gestalt, Hebbs Theory and Information Theory, this study investigates how visual perception will determine the resemblance of a systemised façade to the building envelope it represents, at relevant sensory thresholds. It will be shown that regardless of a systems flexibility, the minimum distance from which a façade is perceived has a substantial effect on offering that resemblance. It will also be shown that at different distances, depending on the size, an object cannot be recognised and hence a systemised façade may be identically perceived as its generating façade. The paper starts with a brief review of different theories with an emphasis on their implications for visual perception and explains how the experience of an observer may be underpinned by the way the visual experiment has been conceived. At the next stage we use a methodology to show how size is perceived at a distance. This has been developed based on practical studies to establish thresholds of recognition and discrimination of the human eye. We will then examine this in an existing building and develop this methodology into a hypothetical case where a systemised façade would be needed to conclude on this practical method. Consequently, future research will be suggested to help take into account a series of other factors which might have an effect on visual perception in the field of architectural design, system design and construction of prefabricated building façades.

Design for sustainability: A comparative study of a customized modern method of construction versus conventional methods of construction

Emergent methods of construction are believed to have achieved higher standards, thereby delivering improved building performance. Added to the higher living standards however, this sometimes proves to be very difficult to evaluate. In addition, the state-of-the-art strategies and methods applied elsewhere, if employed in the construction industry, might not prove as environmentally friendly as they might need to be. This has been used as our core discussion to evaluate new buildings against refurbishment with reference to environmental performance. This article investigates an offsite construction method offering customization against its conventional counterpart in a fairly controlled context. The comparison has been normalized to guarantee most realistic results. We start with a brief introduction to the two educational buildings, followed by a brief overview of customization strategy. We will then argue why the new building can be accounted for as a mass customizable system. The data was collected, collated and analysed, and the environmental impact of two buildings was measured using two different open-source applications. The result shows that despite the higher standards required by law, which in return increases the environmental impacts, the new school building is performing significantly better with a slightly lower environmental impact compared to the old building.

Double skin façade (DSF) technologies for UK office refurbishments: A systemic matchmaking practice

Purpose – The purpose of this paper is to establish how UK offices and double skin facade (DSF) technologies can be best matched for refurbishment purposes. Design/methodology/approach – This research uses a mixed methodology including primary and secondary data collection, analysis and interpolation through document analysis, comprehensive critical literature review, and case study approach. Findings – In total, 22 benchmarks have been developed to represent 75 per cent of the existing office stock in the UK. Through a comparison with 36 case studies of European buildings refurbished with DSFs, two benchmarks showed to be most suitable for a DSF refurbishment and most appropriate configurations for a successful DSF refurbishment have been identified. Findings have been also checked against a large sample of DSF buildings in the UK. Research limitations/implications – The benchmarks delivered in this study can be developed further into parametric models, where variations can be obtained by changing the pa...

Double-Skin Façades for the Sustainable Refurbishment of Non-domestic Buildings: A Life Cycle Environmental Impact Perspective

In developed countries, existing buildings have the biggest share in the building stock. Given the age of construction, the property versus land values, and their slow replacement rate, low-carbon refurbishments are arguably one of the most sensible ways to mitigate environmental impacts (EIs) in the construction sector and meet the greenhouse gas (GHG) reduction targets. In this respect, Double-skin facade (DSF) has been defined as one of the most effective ways to efficiently manage interactions between outdoors and indoors, and its benefits span from passive heating and cooling to the enhancement of thermal comfort of the occupied spaces. A plethora of research does exist on the operational behaviour of the DSF. However, life cycle energy figures and EIs are yet to be established fully and comprehensively. This paper reports on findings of an on-going research project aimed at filling such a gap. More specifically, life cycle assessment (LCA) and building energy modelling (BEM) have been combined to build a methodology to help assess life cycle energy figures in a more holistic manner. Primary data have been collected from manufacturers from across Europe about all the life cycle stages and processes related to a DSF refurbishment. Results show that if on the one hand, the life cycle energy balance actually is negative, hence supporting a wider adoption of DSFs in refurbishments, on the other hand, there exists ecological and EIs that the DSF bears; that cannot be easily overlooked if a more responsive approach to the EIs is to be undertaken. Not only do these findings inform a more energy-efficient deployment of DSFs, but they also highlight the need for a more holistic and impact-driven design approach to ensure that the environmental burdens are not just shifted from one impact category to another.