Research on Ventilation and Heat Insulation Layer Design of Split-Type Roof Greening Based on Topological Interlocking Principle

In this paper,the roof ventilation and heat insulation layer modules are combined with the roof greening,and each module is assembled through the principle of topological interlocking.The assembly of these modules does not require any rivets or cement mortar,and the structural stability of the overall assembled roof is achieved only through the interlocking and limiting the movements of the interlocked units.The green roof designed in this paper has strong applicability and can be applied to roofs of different shapes.Such a roof can not only meet the aesthetic needs,but also beautify the urban environment and reduce carbon emissions.

One-time Shaping Technological System of Lightweight Roof Greening

Lightweight roof greening is an important way for improving urban ecological environment and has good ecological and social benefits, but the investment is- too-high for the investors. Therefore, it is necessary to improve the system of lightweight roof greening. This study introduced a lightweight roof greening mode with low cost, simple construction, rapid formation, good economic benefit and convenient curing.

Sponge-type Composite Vegetation Carpet and Roof Greening Technology

Roof greening is crucial for improving urban eco-environment, showing benefits, ecological y or social y, but it is so hard for investors in terms of capitals or promotion. The research introduced sponge-type composite vegetation carpet techniques and constructionprocess, making a breakthrough in greening form and having formulated a new one.

Developmental Application of Roof Greening against the Background of “Sponge City”: A Case Study of Ningbo City

In view of the problems of architectural eco-civilization in Ningbo City against the background of "sponge city", this paper proposed that development of roof greening in the city met the development concepts of sponge city, summarized six basic countermeasures and four cooperation mechanisms for the developmental application of roof greening in Ningbo City by analyzing practical experience of roof greening construction in foreign countries.

Intelligent Identification of Building Patches and Assessment of Roof Greening Suitability in High-density Urban Areas:A Case Study of Chengdu

With the expansion of a city,the urban green space is occupied and the urban heat island effect is serious.Greening the roof surfaces of urban buildings is an effective way to increase the area of urban green space and improve the urban ecological environment.To provide effective data support for urban green space planning,this paper used high-resolution images to(1)obtain accurate building spots on the map of the study area through deep learning assisted manual correction;and(2)establish an evaluation index system of roof greening including the characteristics of the roof itself,the natural environment and the human society environment.The weight values of attributes not related to the roof itself were calculated by Analytic Hierarchy Process(AHP).The suitable green roof locations were evaluated by spatial join,weighted superposition and other spatial analysis methods.Taking the areas within the Chengdu city’s third ring road as the study area,the results show that an accurate building pattern obtained by deep learning greatly improves the efficiency of the experiment.The roof surfaces unsuitable for greening can be effectively classified by the method of feature extraction,with an accuracy of 86.58%.The roofs suitable for greening account for 48.08%,among which,the high-suitability roofs,medium-suitability roofs and low-suitability roofs represent 45.32%,38.95%and 15.73%.The high-suitability green buildings are mainly distributed in the first ring district and the western area outside the first ring district in Chengdu.This paper is useful for solving the current problem of the more saturated high-density urban area and allowing the expansion of the urban ecological environment.

Green Roof Performance for Stormwater Management in Equatorial Urban Areas Using Storm Water Management Model (SWMM)

Many Low Impact Developments (LIDs) have recently been developed as a sustainable integrated strategy for managing the quantity and quality of stormwater and surrounding amenities. Previous research showed that green roof is one of the most promising LIDs for slowing down rainwater, controlling rainwater volume, and enhancing rainwater quality by filtering and leaching contaminants from the substrate. However, there is no guideline for green roof design in Malaysia. Hence, Investigating the viability of using green roofs to manage stormwater and address flash flood hazards is urgently necessary. This study used the Storm Water Management Model (SWMM) to evaluate the effectiveness of green roof in managing stormwater and improving rainwater quality. The selected study area is the multistory car park (MSCP) rooftop at Swinburne University of Technology Sarawak Campus. Nine green roof models with different configurations were created. Results revealed that the optimum design of a green roof is 100 mm of berm height, 150 mm of soil thickness, and 50 mm of drainage mat thickness. With the ability to reduce runoff generation by 26.73%, reduce TSS by 89.75%, TP by 93.07%, TN by 93.16%, and improved BOD by 81.33%. However, pH values dropped as low as 5.933 and became more acidic due to the substrates in green roof. These findings demonstrated that green roofs improve water quality, able to temporarily store excess rainfall and it is very promising and sustainable tool in managing stormwater.

Understanding the Challenges of Implementing Green Roofs in Multi-Family Apartment Buildings:A Case Study in Khulna

Green roofs are widely recognized for their multifaceted benefits to the environment,economy,and society,constituting the fundamental pillars of sustainability.These roofs contribute to the enhancement of bio-physical diversity,provision of food resources,regulation of temperature and rainfall-runoff patterns,creation of wildlife habitats,and augmentation of aesthetic and recreational value.While Bangladesh,with its favourable climatic conditions and rapid urbanization,possesses immense potential for harnessing the advantages of green roofs,their adoption remains limited in both research and practical applications within the country.Addressing this research gap,the present study aims to investigate the barriers impeding the implementation of green roofs in existing or new multi-family apartment buildings,focusing specifically on the city of Khulna.Through a combination of case studies and a comprehensive questionnaire survey administered to diverse stakeholders including apartment dwellers/owners,architects,developers,and government officials with varying levels of expertise,this research sheds light on the obstacles hindering Green Roof Implementation(GRI).The identified barriers encompass a lack of governmental policies,inadequate technological advancements,inaccurate estimation of economic benefits,and individual resistance.In light of the perspectives of various GRI stakeholders,strategic proposals encompassing policy,technical,economic,and social dimensions are presented to surmount these barriers.The outcomes of this study contribute to the dissemination of knowledge pertaining to the impediments to GRI implementation,thereby inspiring further research endeavours and enabling decision-makers to formulate robust policies facilitating the widespread adoption of green roofs.

Irrigation and Thermal Buffering Using Mathematical Modeling

Two methods of irrigation,drip,and sprinkler were studied to determine the response of the Javits green roof to irrigation.The control study was dry unirrigated plots.Drip irrigation consisted of irrigation tubes running through the green roof that would water the soil throughout and sprinkler irrigation used a sprinkler system to irrigate the green roof from above.In all cases,the irrigated roofs had increased the soil moisture,reduced temperatures of both the upper and lower surfaces,reduced growing medium temperatures and reduced air temperatures above the green roof relative to the unirrigated roof.The buffered temperature fluctuations were also studied via air conditioner energy consumption.There was a 28%reduction in air conditioner energy consumption and a 33%reduction in overall energy consumption between dry and irrigated plots.Values of thermal resistance or S were determined for accuracy and for this study,there was little change which is ideal.A series of infra-red and thermal probe measurements were used to determine temperatures in the air and sedum.It was determined that the sprinkler irrigation did a better job than the drip irrigation in keeping cooler temperatures within the green roof.A Mann-Whitney U test was performed to verify the variation in moisture temperatures buffering energy consumption.By getting a p-value<0.05,it indicates that the model is accurate for prediction and medium temperatures were statistically different.

Assessment of green roof performance for sustainable buildings under winter weather conditions

A green roof is a specialized roof system that supports vegetation growth on rooftops.This technology is rapidly gaining popularity as a sustainable design option for buildings.In order to contribute to an understanding of green roof in regions with cold winters and snow,an on-site experimental investigation was present with a focus on the assessment of green roof performance during the winter.This field experiment took place on a six small buildings during the winter of 2010-2011.The work monitored three buildings with green roofs,two buildings with reference roofs and one building with a bare soil coverage for the roof.These six buildings were identically constructed and instrumented with sensor networks to provide heat flux data through the roofs.The 15 min averaged data were statistically analyzed for a week under the two separate periods,first without a snow cover and second with a snow cover.The results show that the roof type is a significant factor in affecting the thermal performance of these buildings.Most importantly,green roofs reduce heat flow through the roof and thus reduce the heating energy demand during the winter.However,the energy savings for buildings with the green roofs are reduced under snow conditions because the snow diminishes thermal resistance of the roof and increases the heat transfer process through the roofs.

Ecological Function of Urban Green Roof and Analysis of Its Influencing Factors

Based on the analysis of the multiple ecological functions of green roofs, the main factors affecting the ecological functions of green roofs are expounded and the numerical simulation methods for quantitative calculation of ecological functions of green roofs are summarized in order to provide theoretical and method support for the construction of urban green roofs.

Green roofs for storm water management:a review

The rapid urbanization and industrialization involve an unsustainable use of natural systems,leading to various problems in cities.The urban hydrological system experiences fluctuating amount of surface runoff water when it rains heavily.It has been suggested that green roofs significantly mitigate storm water runoff generation even in tropical climate.Green roofs have become popular due to its proven benefits by mitigating urban heat island effects and protecting biodiversity.The annual rainfall and runoff relationship for green roofs is determined by the depth of the substrate.Water retention capacity mostly depends on substrate's physical conditions such as dry or wetness.Generally 6 mm to 12 mm rainfall is required for dry substrate to initiate runoff whereas response of wet conditions is mostly straight.Besides,there are some other factors affecting runoff dynamics such as type of a green roof and its slope,age of green roof,type of vegetation,soil moisture characteristics,weather.The review indicates that there is not much research in green roofs performance over storm water runoff;hence there is a need for further research.This paper reviews and addresses the role of green roofs in urban storm water management.

Application of Green Roof in Relieving Urban Waterlogging: A Review

Green roof plays a critical role in regulating roof runoff by reducing runoff, delaying runoff generation, reducing runoff peak flow and improving runoff water quality effectively. On the basis of introducing significance and role of green roof, this paper reviewed domestic and international researches on the green roof's control over roof runoff, and analyzed the factors that influence the control of green roof over the runoff, so as to provide a theoretical support and method for the construction of green roofs in urban districts.

Thermal Behaviour in Buildings with Green Covers Combined with Natural Ventilation, Green Facades and Green Roofs

The main aim of this paper was to study the influence of ventilation during a typical experimental day, in the internal air temperature as well as in internal surface temperatures under the conditions of the outer environment, using an experimental method which allows a comparison of the thermal performance between four cell tests： a prototype called control （no vegetation） and three with different combinations of vegetation （roofs and facades） installed in a region of tropical climate. The experiments were developed in four test cells with dimensions 2.0 m × 2.50 m × 2.7 m. Measurements of internal surface temperatures and internal air temperatures were collected with the use of specific equipment, a data logger （CR1000, Campbell Scientific Inc.）, connected with two multiplexers 32 channels （416AM Campbell Scientific Inc.）. Data were recorded over a year and a typical heat day was selected, which was September 24, 2015. The results show that ventilation affects the internal temperature of the air, so that this gets even surpass the external temperature. Regarding surface temperatures, increased temperature, except those which are provided with vegetation, namely, the surfaces which have green walls and green roofs file the lower temperatures. Therefore, we can confirm the ability of vegetation to maintain more pleasant internal conditions compared to the test cells built with conventional materials, thus it can reduce cooling load efficiency.

Thermal Response to Heat in Buildings with Green Covers for Tropical Climate： Green Facades and Green Roofs

The main aims of this paper were to study and demonstrate the benefits the plant systems can provide indoors in a critical heat day. This study proposed an experimental method to try to understand the thermal response to heat of four different systems： a prototype called control （no vegetation） and three with different combinations of vegetation （green roofs and green facades） installed in a tropical climate region. The experiments were developed in four test cells with dimensions 2.0 m × 2.50 m× 2.71 m. Measurements of internal surface temperatures and internal air temperatures were collected with the use of specific equipment, a data logger （CR1000, Campbell Scientific Inc.）, connected with two multiplexers 32 channels （416AM Campbell Scientific Inc.）. Data were recorded over a year and a critical day heat was selected, which was September 24, 2015.The results show that the use of plant systems in buildings establishes a passive technique in reducing energy consumption because of the high incidence of summer solar radiation which is reduced and simultaneously, it maintains thermal internal conditions more pleasant than external ones, because of the best thermal behaviour, which was observed in the test cell with vegetation on both roofs and facades. The biggest difference between maximum internal air temperatures registered was 2 ℃.

GREEN ROOFING IN INDIANA: CASE STUDIES AND DESIGN NOTES

Green roof technology and implementation are taking root in North America at an accelerating pace.Growing recogni-tion of the benefits of green roofs and increasing interest in green infrastructure are leading to expansion of green roof tech-nologies that have been in use for decades in Europe and elsewhere.While some regions have adopted the use of green roofs on a large scale,other areas are warming up to the concept more slowly.Large-scale implementation of green roofs has not yet occurred in Indiana,but a number of exemplary projects have been constructed,and there are signs that interest in the technology is increasing in the state.The purpose of this article is to provide an overview of green roof technology,analyze selected green roofs in Indiana,explore trends in the state,and address issues for future development of green roof technol-ogy in the region.A variety of green roofs were investigated throughout the state.Discussions were held with individuals involved in each project to obtain technical and logistical details of green roof design,installation,and performance.

MEDIA COMPOSITION INFLUENCES GREEN ROOF PLANT VIABILITY IN THE OZARK HIGHLANDS

Plant selection and establishment are critical components for green roof health and success. Plant palettes (sets of plant species selected for specific conditions) for green roofs vary in their ability to confer benefits depending on the species make-up and their adaptation to particular environments and climates. The response of various species to climatic factors on rooftops is unknown for the Ozark Highlands region. The objective of this study was to compare plant survival and spread in three growing medium treatments (course and fine texture with compost and fine texture with no compost) installed as part of a green roof system. The study was performed on a green roof system at the University of Arkansas in Fayetteville over 3 years. Data were collected on 13 species installed in September of 2006 and surveyed on three dates thereafter: April 30, 2007;May 19, 2009;September 10, 2009. The treatments with added compost had statistically greater vegetated cover (from 73 to 87%) compared to the fine medium without compost (36 to 43%). In most cases the spread of individual plants was not significantly different between treatments. Results indicated that rooting medium containing compost increased survival and overall vegetated roof coverage, and identified various potential green roof plant species for the Ozark Highland environment. Two species, Sedum middendorffianum var. diffusum and Sedum spurium ‘Roseum’, did particularly well in all treatments. One species, Sedum kamtschaticum, did well only in the treatments with compost.

PRAIRIE-BASED GREEN ROOFS:LITERATURE,TEMPLATES,AND ANALOGS

Native prairie species have been both promoted and questioned in their ability to serve as vegetative covers for green roofs.The green roof environment with its exposure to intense sun and wind and limited moisture restricts the capacity for a large diversity of species.The result has been,in many cases,a standard,low-diversity mix of Sedum species often focused on ornament and minimizes the potential for wider environmental benefits.We reviewed the ecological literature on prairie and grassland communities with specific reference to habitat templates from stressed environmental conditions and examined analogs of prairie-based vegetation on twenty-one existing green roofs.We found that many,but not all prairie and grassland species will survive and thrive on green roofs,especially when irrigated as needed or given adequate growing medium depth.We raise several important questions about media,irrigation,temperature,biodiversity and their interactions needing more study.

THE ADOPTION OF AN INNOVATION:BARRIERS TO USE OF GREEN ROOFS EXPERIENCED BY MIDWEST ARCHITECTS AND BUILDING OWNERS

While green roof technologies are increasingly employed in Northern European countries,adoption is progressing at amuch slower rate in the US.This manuscript discusses results of a survey that quantified knowledge,barriers,and perceivedcosts and benefits to use of green roof technology among a sample of architects and building owners in the Midwest.The survey also examined conditions that may encourage use of this technology among the respondents.Resultsshow that many respondents do not fully recognize the economic or performance advantages offered by green roof technologies.The payback period for economic advantage is longer than owners are willing to consider.Both owners andarchitects possess a wide range of misconceptions about the performance advantages of green roofs.While green roof technologyoffers clear environmental advantages such as reduced stormwater runoff,increased habitat,and cooler temperaturesthat mitigate heat island effects,many building owner respondents either do not know about or value these advantages.This research quantified potential adopters’perceptions of an innovative technology and the survey results areinterpreted and discussed within the conceptual framework of innovation diffusion literature.Strategies to hasten theadoption of green roof technology are suggested.

THERMAL PERFORMANCE OF GREEN ROOF PANELS IN SUB-ZERO TEMPERATURES

To date,much of the research on green roof technology has focused on the capacity for these systems to contribute to the cooling of buildings during summer months.The thermal performance of green roofs in cold climate conditions is critical to understanding the potential of these roofs to decrease energy use in buildings during winter.This paper compares the behavior of two green roof systems with that of a conventional built-up roof by making use of a novel hot box testing apparatus.The green roofs tested are classified as extensive systems.Each system included:a 3 mm thick styrene butadiene rubber waterproofing membrane,0.2 mm thick polyethylene slip sheet,a 76 mm thick extruded polystyrene insulation layer,2 mm thick filter fabric,a 51 mm drainage layer followed by a 2 mm thick filter cloth,either 100 mm or 150 mm growing medium,and a 25 mm thick wild flower vegetated mat.The conventional roof consisted of a 2 mm thick layer of Kraft™vapour retarder bonded with insulation adhesive,51 mm of isocyanurate insulation,25 mm of fibreboard,a three ply(2 mm)cold-applied built-up roof membrane,and a gravel ballast finish 51 mm thick.Each roof was subjected to temperatures between 0℃ and–25℃,while the temperature within the hot box was held at 21℃.The effect of vegetation on a green roof to reduce wind speeds or increase snow cover were not considered in this study.The power required,as well as the temperatures throughout each system at steady state conditions,were monitored for 5 hours.The data collected from thermal testing suggests that the R-value of green roofs with 100 mm or 150 mm thick layers of growing medium is 37%higher than a conventional roof when subjected to temperatures of 0℃ to–25℃.