Green Roof Evaluation: A Holistic ‘Long Life, Loose Fit, Low Energy’ Approach

Green roofs have potential to improve the social and environmental performance of detached housing in Australia, yet often they are overlooked due to prohibitive capital cost and a range of other perceptions that are difficult to quantify. A classic evaluation problem is invoked that must balance short and long term benefits. Using two distinct designs of the same floor area, green roof and traditional housing prototypes are analysed to determine the relative ‘breakeven’ point when long-term benefits become feasible. It is discovered that green roofs are unlikely to be viable in their own right, but when coupled with an overall design strategy of long life (durability), loose fit (adaptability) and low energy (sustainability) they can deliver least cost (affordability) over time as well as unlock valuable social and environmental rewards. This outcome can be realised within 25% of a home’s expected design life of at least one hundred years. The results demonstrate that residential green roofs, when integrated as part of a holistic approach, can be both individually and collectively justified on key economic, social and environmental criteria, and are therefore able to claim a valuable contribution towards wider sustainable development goals.

Download Full-text

Substrate Depth Influences Sedum Plant Community on a Green Roof

HortScience ◽

10.21273/hortsci.44.2.401 ◽

2009 ◽

Vol 44 (2) ◽

pp. 401-407 ◽

Cited By ~ 45

Author(s):

Kristin L. Getter ◽

D. Bradley Rowe

Keyword(s):

Plant Community ◽

Plant Stress ◽

Green Roof ◽

Green Roofs ◽

Plant Performance ◽

Blue Spruce ◽

Waterproofing Membrane ◽

Substrate Moisture ◽

Substrate Depth

Because the waterproofing membrane beneath green roofs is estimated to last at least 45 years, long-term plant performance beyond initial establishment is critical. Plants that survive initially on a green roof may not exist in the long term because of variability in climate and other factors. This study evaluated the effect of green roof substrate depth on substrate moisture, plant stress as measured by chlorophyll fluorescence, and plant community development and survival of 12 Sedum species over 4 years in a midwestern U.S. climate during 4 years of growth. Plugs of 12 species of Sedum were planted on 8 June 2005 and evaluated biweekly for absolute cover (AC). Most species exhibited greater growth and coverage at a substrate depth of 7.0 cm and 10.0 cm relative to 4.0 cm. For the species evaluated, substrate depths of at least 7.0 cm are highly recommended. AC of Sedum was significantly greater at this substrate depth than at 4.0 cm. Mean volumetric moisture content of the three substrate depths followed the same pattern as AC. When averaged over time, the 4.0-cm substrate depth held less moisture than depths of 7.0 or 10.0 cm, whereas the 7.0- and 10.0-cm substrate depths were statistically the same. Species exhibiting the greatest AC at all substrate depths were S. floriferum, S. sexangulare, S. spurium ‘John Creech’, and S. stefco. In general, species that are less suitable at these substrate depths are S. ‘Angelina’, S. cauticola ‘Lidakense’, S. ewersii, S. ochroleucum, and S. reflexum ‘Blue Spruce’.

Download Full-text

Stormwater Retention and Reuse at the Residential Plot Level—Green Roof Experiment and Water Balance Computations for Long-Term Use in Cyprus

Water ◽

10.3390/w11051055 ◽

2019 ◽

Vol 11 (5) ◽

pp. 1055 ◽

Cited By ~ 5

Author(s):

Katerina Charalambous ◽

Adriana Bruggeman ◽

Marinos Eliades ◽

Corrado Camera ◽

Loukia Vassiliou

Keyword(s):

Water Balance ◽

Plant Species ◽

Rainwater Harvesting ◽

Green Roof ◽

Irrigation Treatment ◽

Stormwater Runoff ◽

Green Roofs ◽

Roof Experiment ◽

Stormwater Retention

Green roofs can provide various benefits to urban areas, including stormwater retention. However, semi-arid regions are a challenging environment for green roofs as long dry weather periods are met with short but intense rainfall events. This requires green roofs to retain maximum volumes of stormwater, while being tolerant to minimal irrigation supplies. The objectives of this study are (i) to quantify the stormwater retention of two substrate mixtures with two plant species under natural rainfall; (ii) to assess the performance of two plant species under two levels of deficit irrigation; and (iii) to compute stormwater runoff reduction and reuse by green roofs and rooftop water harvesting systems for three standard residential plot types in urban Nicosia, Cyprus. A rooftop experiment was carried out between February 2016 and April 2017 and results were used to compute long-term performance. Average stormwater retention of the 16 test beds was 77% of the 371-mm rainfall. A survival rate of 88% was recorded for Euphorbia veneris and 20% for Frankenia laevis, for a 30% evapotranspiration irrigation treatment. A combination of a green roof, rainwater harvesting system and 20-m3 tank for irrigation and indoor greywater use reduced stormwater runoff by 47–53%, for the 30-year water balance computations.

Download Full-text

Monitoring and Modeling the Long-Term Rainfall-Runoff Response of the Jacob K. Javits Center Green Roof

Water ◽

10.3390/w10111494 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1494 ◽

Cited By ~ 7

Author(s):

Noura Abualfaraj ◽

Joseph Cataldo ◽

Yara Elborolosy ◽

Daniel Fagan ◽

Sloane Woerdeman ◽

...

Keyword(s):

New York ◽

Environmental Protection Agency ◽

Green Roof ◽

Substantial Reduction ◽

Cost Effective ◽

Green Roofs ◽

The United States ◽

Rainfall Runoff ◽

Substrate Depth

Drainage from the 27,316-m2 Jacob K. Javits Convention Center (JJCC) green roof was investigated in the field to quantify the system’s long-term rainfall-runoff response. The JJCC hosts one of the largest extensive green roofs in the United States. Utilizing four years of rooftop monitoring data collected using a weather station, custom designed and built drainage systems, three Parshall flumes equipped with pressure transducers, and weighing lysimeters, this study quantified the 25.4-mm-deep green roof’s ability to decrease the volume and peak rate of runoff. With parameters derived from the site, the Environmental Protection Agency Stormwater Management Model (EPA-SWMM) predicted event total runoff volume and event peak runoff rates to within +10% to −20% and +25% to −15% of the observations, respectively. The analysis further indicated that approximately 55% of the cumulative precipitation that fell on the JJCC extensive green roof during the monitoring period (warm weather months, June 2014–November 2017) was captured and retained. The average percent retained on an event-basis was 77%, and average event runoff coefficient was 0.7, implying a substantial reduction in the volume and rate of runoff generated from the roof compared to the pre-green roof condition, when most, if not all, of the precipitated water would have immediately resulted in runoff. Our research suggests that, on average, 96% of rainfall events 6.35 mm or less were retained within the green roof, whereas 27% of the total event volume was retained for events greater than 12.7 mm in depth. A sensitivity analysis suggests if the substrate depth were increased, better stormwater capture performance would be achieved, but only up 127 mm, whereas increased precipitation coupled with warmer temperatures as a result of climate change could decrease the performance by up to 5%, regardless of substrate depth. An equivalency analysis suggested that even shallow green roofs can significantly reduce the required stormwater detention volume that New York City requires on new development. This particular green roof appears to be more than 18 times as cost-effective as a subsurface cistern would be for managing an equivalent volume of stormwater in Midtown Manhattan.

Download Full-text

Hydrological Performance of Green Roofs at Building and City Scales under Mediterranean Conditions

Sustainability ◽

10.3390/su10093105 ◽

2018 ◽

Vol 10 (9) ◽

pp. 3105 ◽

Cited By ~ 8

Author(s):

Ignacio Andrés-Doménech ◽

Sara Perales-Momparler ◽

Adrián Morales-Torres ◽

Ignacio Escuder-Bueno

Keyword(s):

Green Roof ◽

Drainage System ◽

Green Roofs ◽

Hydrological Models ◽

The Mediterranean ◽

Dry Climates ◽

One Year ◽

The City ◽

Mediterranean Conditions

Green roofs are one specific type of sustainable urban drainage system (SUDS); they aim to manage runoff at the source by storing water in its different layers, delaying the hydrological response, and restoring evapotranspiration. Evidence of their performance in the Mediterranean is still scarce. The main objective of this paper is to analyse the hydrological performance of green roofs at building and city scales under Mediterranean conditions. A green roof and a conventional roof were monitored over one year in Benaguasil (Valencia, Spain). Rainfall and flow data were recorded and analysed. Hydrological models were calibrated and validated at the building scale to analyse the hydrological long-term efficiency of the green roof and compare it against that obtained for the conventional roof. Results show that green roofs can provide good hydrological performances, even in dry climates such as the Mediterranean. In addition, their influence at the city scale is also significant, given the average runoff coefficient reduction obtained.

Download Full-text

Investigating green roofs’ CO2 sequestration with cold- and drought-tolerant plants (A short- and long-term carbon footprint view)

10.21203/rs.3.rs-308004/v1 ◽

2021 ◽

Author(s):

Mohammad Reza Seyedabadi ◽

Mohsen Karrabi ◽

Jafar Nabati

Keyword(s):

Carbon Footprint ◽

Carbon Emission ◽

Green Roof ◽

Green Roofs ◽

Gas Analysis ◽

Construction Process ◽

Long Term Effects ◽

Light Intensities ◽

Short And Long Term

Abstract In recent years, green roofs have become the subject of increasing interest because of their good aesthetic qualities, energy conservation, and ability to reduce thermal island effect and absorb greenhouse gases, especially carbon dioxide (CO2). Given the typically significant carbon emission of construction activities, adding any extra component to a structure increases the amount of carbon to be released during the execution stage. This also applies to green roofs, which require more materials and more extensive construction activities than traditional roofs. However, plants of green roofs absorb substantial amounts of CO2 during their lifetime, thus leaving both short- and long-term positive impacts on the building’s carbon footprint. This study investigated the short- and long-term effects of green roofs on carbon footprint, as compared to conventional roofs. For this investigation, the CO2 uptake of eight plant species with suitable drought- and cold-resistant properties was measured by Infrared Gas Analysis (IRGA) and the effect of green roof on the building’s carbon footprint was analyzed using the software Design Builder. The results showed that building a green roof instead of a traditional roof increases the carbon emission of the construction process by 4.6 kilograms per square meter of roof area. Investigations showed that, under high light intensities (1500–2000 µmol/m2.s), Sedum acre L has the best performance in compensating the extra carbon emission imposed on the construction process (in 264 days only). Under low light intensities (1000–1500 µmol/m2.s), Frankenia laevis showed the best increase in the amount of carbon uptake (2.27 kg/m2.year).

Download Full-text

Analysis of pre-service teachers’ perception towards the economic, environmental, social and cultural dimensions of Education for Sustainable Development

Think India ◽

10.26643/think-india.v22i3.8435 ◽

2019 ◽

Vol 22 (3) ◽

pp. 972-978

Author(s):

Manisha Jetly ◽

Dr. Nandita Singh

Keyword(s):

Sustainable Development ◽

Environmental Sustainability ◽

Qualitative Content Analysis ◽

Holistic Approach ◽

Education For Sustainable Development ◽

Cultural Dimensions ◽

The Sustainable Development ◽

Depth Study ◽

Development Goals ◽

Class Room

Education for sustainable development (ESD) enjoys a huge momentum worldwide in which the role of teachers for making sustainable development goals a reality has been recognized significantly. Teachers through their knowledge, attitudes and skills can bring the learning about these concepts to the curriculum and class room interaction and are in a position to influence their students. Therefore it is pertinent, that teachers are sensitised towards these issues, so that they prepare and nurture their students for making appropriate and responsible choices which contribute to a sustainable future. At this juncture it becomes crucial to understand their priorities and awareness level in context of the sustainable development. The present research paper aims to analyse the perception of forty post graduate pre-service teachers of the Chandigarh region, towards ESD through the dimensions of economic sustainability, environmental sustainability, social sustainability and cultural sustainability. For this researchers have adopted qualitative content analysis methodology for an in-depth study of the subjective responses through an open ended question. The findings suggest that most of the respondents associated the perception of ESD strongly with environmental sustainability. It is noted that the pre-service teachers lack a holistic approach towards ESD. On the basis of the findings it is recommended that there is an urgent need of integrating the concept of ESD consciously and conscientiously in India’s teacher education programmes.

Download Full-text

Seismic Performance of a Green Roof Structure

Sustainability ◽

10.3390/su13084278 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4278

Author(s):

Svetlana Tam ◽

Jenna Wong

Keyword(s):

Green Roof ◽

Time History ◽

Green Roofs ◽

Moment Frame ◽

Steel Moment Frame ◽

Roof Structure ◽

Nonlinear Time History Analyses ◽

Vegetated Roofs ◽

Nonlinear Time History ◽

The Impact

Sustainability addresses the need to reduce the structure’s impact on the environment but does not reduce the environment’s impact on the structure. To explore this relationship, this study focuses on quantifying the impact of green roofs or vegetated roofs on seismic responses such as story displacements, interstory drifts, and floor level accelerations. Using an archetype three-story steel moment frame, nonlinear time history analyses are conducted in OpenSees for a shallow and deep green roof using a suite of ground motions from various distances from the fault to identify key trends and sensitivities in response.

Download Full-text

COVID-19 Response in Thailand and Its Implications on Future Preparedness

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18031089 ◽

2021 ◽

Vol 18 (3) ◽

pp. 1089

Author(s):

Wijitbusaba Marome ◽

Rajib Shaw

Keyword(s):

Early Stage ◽

Health Resources ◽

Holistic Approach ◽

Disaster Risk ◽

Community Level ◽

Multilateral Cooperation ◽

First Case ◽

Multiple Dimensions ◽

Economic And Social Impacts

Thailand has been affected by COVID-19, like other countries in the Asian region at an early stage, and the first case was reported as early as mid-January 2020. Thailand’s response to the COVID-19 pandemic has been guided by the “Integrated Plan for Multilateral Cooperation for Safety and Mitigation of COVID-19”. This paper analyses the health resources in the country and focuses on the response through community-level public health system and legislative measures. The paper draws some lessons on future preparedness, especially with respect to the four priorities of Sendai Framework for Disaster Risk Reduction. At the end, the paper puts some key learning for future preparedness. While Thailand’s response to COVID-19 has been effective in limiting the spread of the disease, it falls short at being able to address the multiple dimensions of the crisis such as the economic and social impacts. The socioeconomic sectors have been hardest hit, with significant impact on tourism sectors. Sociopolitical system also plays an important role in governance and decision-making for pandemic responses. The analysis suggests that one opportunity for enhancing resilience in Thailand is to strive for more multilevel governance that engages with various stakeholders and to support grassroots and community-level networks. The COVID-19 pandemic recovery is a chance to recover better while leaving no one behind. An inclusive long-term recovery plan for the various impacted countries needs to take a holistic approach to address existing gaps and work towards a sustainable society. Furthering the Health Emergency Disaster Risk Management (HEDRM) Framework may support a coordinated response across various linked sectors rather than straining one particular sector.

Download Full-text

EU Labor Market Inequalities and Sustainable Development Goals

Sustainability ◽

10.3390/su13052675 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2675

Author(s):

Elena Jianu ◽

Ramona Pîrvu ◽

Gheorghe Axinte ◽

Ovidiu Toma ◽

Andrei Valentin Cojocaru ◽

...

Keyword(s):

Sustainable Development ◽

Labor Market ◽

Policy Issue ◽

Policy Makers ◽

Public Policy Issue ◽

Development Goals ◽

To Come ◽

Business Practitioners ◽

The Eu

Reducing inequalities for EU citizens and promoting upward convergence is one of the priorities on the agenda of the European Commission and, certainly, inequality will be a very important public policy issue for years to come. Through this research we aim to investigate EU labor market inequalities, reflected by the specific indicators proposed for Goal 8 assumed by the 2030 Agenda for Sustainable Development, based on cluster analysis for all the 27 Member States. The research results showed encouraging results from the perspective of convergence in the EU labor market, but also revealed a number of analyzed variable effects that manifested regional inequalities that were generated in the medium and long term. Based on the observations made, we want to provide information for policy-makers, business practitioners, and academics so as to constitute solid ground for identifying good practices and proposing to implement policies aimed at reducing existing inequalities and supporting sustainable development.

Download Full-text