Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sustainable garden roofs developed as a new construction material

21.11.2008
A Spanish research study has tested different combinations of supports and indigenous plants to determine which are the best for reducing energy consumption inside buildings. This type of roof is a “rurban”, sustainable architectural solution that will lead to a reduction in environmental and acoustic contamination levels in cities, and be visually pleasing.

Researchers from the Polytechnic University of Madrid (UPM) have built a roof covered with plants and a watering system that will optimise the consumption of a building’s heating and cooling systems thanks to its insulation. It is a third-generation ecological roof, characterised by its sustainability and the use of indigenous plant species.

“The importance of the roofs”, explained Francisco Javier Neila, Professor at the UPM and co-author of the study, to SINC, “is that each geographical area requires the structures and plant species that work best”. In this case, the researchers divided the roof of an experimental building in Colmenar Viejo (Madrid) into 20 modules, and carried out a test with different supports and regional plants based on three factors: the plant growing at a good speed, the density of the biomass perfectly covering the roof and the result being visually attractive.

Indigenous species work better

In winter and summer conditions, the best performing roof has an 8 cm tank that collects rainwater and offers an even irrigation system.

Plants such as sedum (Sedum praealtum) or aptenia (Aptenia cordifolia) provide the best insulation “because they have a thick leaf and are resistant to frosts and heat”, indicated Neila. But each location where an ecological roof is installed will have its own catalogue of plants, starting with indigenous plants “because in its habitat, the plant performs better”.

The researchers also considered covering the roofs with an effective plant and decorating it with another prettier one to fulfil both requirements, but the result is difficult ,“since when a single space is shared by two species, the stronger one will predominate”, Neila explained.

There are a series of superimposed layers under the groundcover. The first is a very light special substrate which helps to drain rainwater quickly so the plant does not drown. Here, the best solution is pine bark crushed and mixed with sewage sludge.

The substrate lies on porous concrete which acts as a sieve for excess water that will end up in the tank, the capacity of which is controlled by raised floor systems similar to those that support the raised floor of an office. The water contained rises up to the roof through capillary action and enables even irrigation. Just before the building’s floor framing, the roof consists of a waterproof sheet which prevents leaks.

Between each layer an extruded polystyrene sheet is inserted which, according to the roof model, can be situated under the porous concrete or beneath the tank. Each layer also includes a sensor that measures temperature and humidity variables which can be compared with data collected by an adjoining weather station for checking any change caused by the roof during the four seasons of the year.

The researchers have also left various modules without an ecological roof to clearly demonstrate its effectiveness. “Roof areas with plants optimise better the heating and cooling of a building than a normal structure, regardless of how well insulated it is”, the expert commented to SINC.

‘Rurban movement’

The design of ecological roofs responds to the challenge of merging urban and rural lifestyles and is being developed in countries such as Germany, Switzerland, the USA and South Africa. Ecological roofs reduce pollution in cities, absorb lead and other organic components. “A forest would be less contaminated with the same intensity of urban pollution", said Neila.

These roofs will help to reduce the temperature of cities, which today are a kind of urban heat island. Scientists have also estimated that acoustic contamination would be reduced to three decibels, thanks to plant absorption.

Groundcover is therefore becoming a new type of building material but development prospects are not positive due to its high price. Neila cites Germany, “where the situation is being resolved with tax benefits, council taxes, increase in suitability for building, which means it does not cost developers so much to invest in this option”.

SINC Team | alfa
Further information:
http://www.plataformasinc.es

More articles from Studies and Analyses:

nachricht When a fish becomes fluid
17.12.2018 | Institute of Science and Technology Austria

nachricht Some brain tumors may respond to immunotherapy, new study suggests
11.12.2018 | Columbia University Irving Medical Center

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Data storage using individual molecules

Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.

Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Pressure tuned magnetism paves the way for novel electronic devices

18.12.2018 | Materials Sciences

New type of low-energy nanolaser that shines in all directions

18.12.2018 | Physics and Astronomy

NASA research reveals Saturn is losing its rings at 'worst-case-scenario' rate

18.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>