Extensive Green Roof: depth 3 - 5 inches; plants: Mosses, Sedums, Succulents, Herbs and few Grasses; Low maintenance and costs

IKEA opened its doors in Budapest in 1990. This was the very first store in Hungary. Twelve years later, the store announced that it would install a green roof. The main purpose of the green roof was to compensate the locals for the loss of green space. The green roof was intended to create a biologically active surface that fits in aesthetically into the suburban landscape and provide a home for animals such as pollinators. The green roof, built in 2002, was covered with a Sedum carpet. In 2014, when the original Sedum vegetation died out, the green roof was completely removed. Then, during the autumn 2014 planting, four types of Sedum shoots were seeded. This was followed in the spring of 2015 by the seeding of herbaceous dicots seed mixes, which contained seeds of roughly 50 plant species. The vegetation is regularly monitored by ecologists: in 2021, more than 160 different taxa were recorded, including spontaneously occurring species. The green roof is closed, not accessible to the public, however tours are occasionally organized for professionals [3] [6] [8] [9] [10] [11].

Banyuwangi International Airport in East Java is the first green airport in Indonesia and was recognized with an award from the Aga Khan Award for Architecture (AKAA) in 2021-22, the world's oldest and most prestigious architecture awards (1,2,3,4). This project was designed and implemented by Architect Andra Matin in 2018 as a corporate social responsibility project for the Banyuwangi Regional Government, Java, Indonesia (1,2,4). The project building was extensively inspired by the houses of the local Osing tribe (1,2). The project aimed to embody a highly efficient passive design, with its remarking green roof feature of a total area of 4765m2 that is planted with grass and routinely maintained (1,2,3,5,6). The green roofs act like a sponge for heat, light and water and conserve energy by maintaining a constant temperature inside the building, and as a result, the airport does not require air conditioning in the main area (5). The green roof of the airport improves air quality as it captures airborne pollutants and atmospheric deposition, and the plants on green roofs also filter noxious gases (5). The eco-friendly airport terminal construction utilizes 'Fast Flow Siphonic System', especially for conventional roof drainage (5). The regional government declared a 10 km radius 'No Development Zone' around the project, protecting the existing paddy fields and villages, which is an exceptional move given the general tendency to exploit land around airports commercially (1,2). The current airport site caters to around 300,000 passengers annually and allows for future expansion to accommodate up to 3 million passengers without encroaching on the No Development Zone (2).

The green roof development forms a 400-meter-long floating green ribbon above the SM North EDSA mall in Quezon City, Philippines. [3] It boasts a 15000m2 area filled with 55 species of native trees, bushes, and flowers that thrive in the local climate, and it relies on stored rainwater runoff to sustain its plant life. Visitors can access the mall via entrances located within the garden's openings and tunnels leading to shops and cafes nestled beneath the botanical landscape. A meandering pathway guides visitors through the space, which features various entertainment options. The garden provides a unique and innovative space for mall-goers and city dwellers to relax and interact with nature. [1,2]

Asia is one of the fastest economic growing regions and so are many cities on the Asian continent. Economic growth brings forward many challenges including intensive urban development, loss of natural features, increased urbanization, and high levels of air pollution, just to name a few. One of these cities is Ho Chi Minh where it was assessed that only 0,25% of its area is covered with vegetation, and in addition to this, there is traffic congestion and air pollution (3).
In an effort to rectify some of these transgressions, a private initiative developed a house called the House of Trees, located in Tan Binh district, one of the most densely populated residential areas in Ho Chi Minh City, where many small houses are crowded together (2).
The green features of the house include five roofs that function as gardens thanks to a layer of earth substratum, from which tall tropical trees grow (3). The aim of the project is to bring green space back into the city, accommodating high-density dwellings with big tropical trees. Five concrete boxes are designed as "pots" to plant trees on their tops. With a thick soil layer, these pots also function as storm-water basins for detention and retention, hence contributing to reducing the risk of flooding in the city. The project has been conducted by Vo Trong Nghia Architects, a leading Vietnamese firm in building green architecture in urban Vietnam. (1)

Penang is a state located in north-western Peninsular Malaysia with an area of 1,049 km2. It comprises two local authorities, Penang Island and the mainland. The former is further divided into five administrative districts which are further divided into mukims (sub-districts). Two urban mukims located on the island – George Town and Bayan Lepas – are the focus of the proposed nature-based solutions (NBS) climate adaptation programme. The programme was launched in 2022 by UN-Habitat in collaboration with the Ministry of Environment and Water (KASA) of Malaysia, Penang Island City Council (Majlis Bandaraya Pulau Pinang - MBPP), Department of Irrigation and Drainage (Jabatan Pengairan Dan Saliran - JPS) and Think City (a wholly-owned subsidiary of Khazanah Nasional Berhad (the sovereign wealth fund of the Government of Malaysia)). (Ref 1)

The implementation of the project responds to several challenges posed by climate change including heatwaves and flooding (Ref 4). The main goal of the programme is to enhance urban resilience and reduce human and ecosystem health vulnerability to climate change impacts and extreme weather events by implementing nature-based solutions (NBS) such as tree-lined streets, pocket parks, green parking spaces, green facades and rooftops, urban agriculture and blue-green corridors to reduce surface temperatures and stormwater runoff, as well as to increase social resilience and build institutional capacity (Ref 1, 3).

The project focuses on encouraging residents of Rio de Janerio's Arará favela to install green roofs on their homes, primarily to reduce the urban heat island effect but also to harness the broader social, environmental, and economic benefits which green roofs can provide, "...from providing thermal protection and improving air quality to mitigating stormwater runoff pollution and saving costs for both residents and cities" (Refs. 2 & 3). The individual behind the project, Luis Cassiano Silva, further hopes that introduction of green roofs into the favela which help to improve residents’ quality of life and "describes the emotional benefits of incorporating green space into the favela landscape" (Ref. 2).

Al Shaheed Park is the largest park in the country. The park was designed to include besides its green spaces, several buildings (museums, parking) populated with green roofs and an artificial lake. The size of the park with all the mentioned grey and green elements stands at 20 ha. The park is viewed as an encompassing part of a green belt that surrounds the city of Kuwait. From an environmental point of view, the park was built to protect the city from sandstorms and to reduce air pollution. From a cultural point of view, the park and the museums are providing the public with high-quality programs, events and spaces, and part of their mission is to spread awareness and educate the public on the importance of the country’s land, history and environment, in addition to the encouragement of international and regional exchange of arts. In addition, the park is meant to commemorate the victims of the first Gulf War. (1,2,3)

One of the first public institutions to rise to the climate change challenge in the Philippines is the LLDA, which unveiled a two-wing, four-story green building in Quezon City to mark its 48th anniversary in 2014.
Reflecting the critical mandate of the LLDA to protect the country’s largest freshwater lake, the LLDA building features its own water treatment facility, material recovery facility, and a rain collection system that can hold 60,000 gallons of water. In order to be certified by the Building for Ecologically Responsive Design Excellence, several greened areas have been installed in the building: two “pocket gardens” on intermediate levels and a green roof (Bio Roof) which covers an area of 208 m2. The Bio Roof is integrated within the building’s structure. Its vegetative layer protects the waterproofing membrane from climatic extremes, which allows for the reduction in maintenance and the reduction in the size of stormwater handling facilities. [1]

As a solution to the increasing population, pollution and high energy consumption, the municipal government of Shiraz has launched the Green City project in 2008. The main aim of this initiative is to reforest the city's periphery and encourage citizens to plant gardens on rooftops and the private sectors to adhere to the city’s development plan with all construction projects. [1]

Since 2008, the City of Portland, Oregon has used various policies and programming to encourage the use of eco-roofs (vegetated roofs) throughout the city to address stormwater management (Ref. 2,3,4). In addition to stormwater management, eco-roofs have the benefits of: saving energy, reducing pollution and erosion in waterways, preserving fish habitats, creating new habitats for birds and insects, absorbing carbon dioxide, cooling urban heat islands, filtering air pollutants, and providing urban green space (Ref. 1,5). From 2008 to 2012, the City of Portland used the Ecoroof Incentive program to encourage property owners and developers to construct ecoroofs (Ref. 4,5,12). In 2018, the City of Portland adopted a mandate for ecoroofs in new buildings (Ref. 2,3,12). These policies and programs led to a growing interest in the use of ecoroofs, and resulted in the construction of over 130 ecoroofs (Ref. 3,4,11).