Despite only gaining prominence in the industry’s collective thought process within the past twenty years, sustainable technology is taking centre stage in modern design and construction processes. In the UK, 45% of carbon emissions originate from the built environment. When constructed, these buildings also emit energy and produce waste materials, but designers and industry experts are only just beginning to take a closer look at the effect the built environment has on the natural world around us. As a result, new technologies are springing up, each with an innovative means of reducing the carbon impact of either the design, construction process or the finished structure. Here are just four simple innovations to help make your construction projects more sustainable.
Green and smart roofs
One of the most widely used sustainable technologies in modern construction, green roofs are all about enabling structures to make better use of natural resources, whilst limiting their impact on the surrounding environment. The green roof, or roof garden, is constructed from an impenetrable membrane base layer to prevent leaks into the structure. This is then covered with lightweight soil and a specially selected mix of vegetation designed to withstand torrential rain and periods of drought.
During periods of intense rainfall, the ‘green roof’ absorbs a some of the water, limiting the runoff that would otherwise flood the already saturated areas. The relatively cheap construction costs have made the green roof a popular feature to integrate into existing residential buildings, but when incorporated on a large scale, they can have a significant impact on the amount of runoff left over after a heavy rainfall.
Smart roofs, on the other hand, can play a significant role in reducing the amount of energy required to maintain an optimum temperature inside a building. To construct a smart roof requires materials capable of reflecting solar rays whilst emitting any absorbed heat slowly throughout the day. In doing so, the building below maintains a consistent internal temperature and requires less energy for cooling.
A green roof in Toronto, Canada. Image by Sookie under CC BY 2.0 license
Smart façade & smart glass
For buildings with a glass façade, smart glass has become an invaluable resource for increasing efficiency and reducing outgoing costs. Thermochromic glass alters colour or transparency according to the amount of heat it has been exposed to. Using thermochromic glass can help filter sunlight during the summer months whilst remaining transparent and allowing in light during the cold winter months, saving money and energy on internal temperature control.
Intelligent glass filters out sunlight and retains heat; intelligent façades are based on the same principle of introducing a control point between the interior and exterior.
Incorporating a smart façade, or ‘skin’ can save up to 35% on energy consumption in large buildings. New technologies, like the Green House in Germany, push the concept of the intelligent façade to new boundaries. Developed by a team of designers from Splitterwerk Architects and Arup, the building’s walls are tinted with millions of microscopic algae. The algae are fed a combination of oxygen and nutrients, which when combined with external light, begins to grow. This growth is harnessed as energy, which is then used inside the building. Similarly, a new hospital under construction in Mexico City utilises the environment around it to increase the quality of life for people inside the building. The Torre de Especialidades is shielded with a façade coated with titanium dioxide, a pigment used in sunscreen capable of neutralizing air pollution in the surrounding atmosphere. The façade eliminates toxins in the air by releasing spongy free radicals, with the potential to counteract the equivalent smog produced by 8,750,100 cars driving by each day.
The Torre de Especialidades is shielded with a façade coated with titanium dioxide, a pigment used in sunscreen capable of neutralizing air pollution in the surrounding atmosphere. The façade eliminates toxins in the air by releasing spongy free radicals, with the potential to counteract the equivalent smog produced by 8,750,100 cars driving by each day.
Smart façades can reduce the amount of heat lost from a building during winter, and heat absorbed into a building during summer
Water reuse and collection features
Construction, and indeed the whole world, faces a growing issue in water consumption. This applies both to the process of construction, and the resulting structure. When a new building is constructed, the rainwater that would usually soak down into the soil beneath cannot be absorbed. This results in flooding and contaminants running into rural areas, polluting the plants and contaminating the soil. Innovative minds across the world have come together to develop technologies to offset the damage these developments can cause.
Porous paving has been in use for several years now, but it’s only just seeing widespread application across the industry. Likewise, well-positioned tree box filters absorb the surplus runoff from built up areas and prevent flooding. The filters sit under the trees and capture pollutants from the runoff, which is then filtered out before allowing the excess water to drain into other vegetative areas.
Tree box filters not only improve add natural beauty to urban development’s, they store storm and flood runoff and prevent excess water water logging other areas. Soil amendments work in the same way; requiring the combination of just a few soil types which are then introduced to areas of significant rainfall. The appeal of soil amendments lies in its simplicity and low cost, meaning it can be used in almost any new project whilst considerably reducing the impact of the development on the surrounding natural environment.
A demonstration of porous paving, specially designed to absorb rainfall and prevent flooding
Recycled construction materials
Despite being an integral aspect of the construction process, the use of recycled materials has, until recently, often been seen as a secondary consideration. Contractors and designers alike have traditionally associated recycled construction materials with substandard quality in the finished design. In the UK, 32% of landfill waste comes from the construction and demolition of buildings and 13% of products delivered to construction sites are sent directly to a landfill without being used.
The National Association of Home Builders’ found that 75% of construction waste could be recycled. In China, the rapid rate of urbanisation may have fuelled a boost in construction, but it has also led to unprecedented levels of construction waste. Locals in Shenzhen blamed poor disposal practices and a lack of legal supervision for a recent landslide, and environmental campaigners are now arguing that the dumping of construction materials has led to an increase in water pollution.
Despite this, the industry is waking up to the advantages of using recycled materials. Contractors, designers and clients are slowly beginning to realise the potential these recycled materials possess. This can only be a good thing, with recycled materials benefiting everyone. The environment benefits from reduced waste being sent to landfills, the designers and contractors benefit from reduced material and waste disposal costs, and these savings are then passed on to the client. Subsequently, firms can advertise their reputation for ecological awareness and lower construction costs to gain an increased advantage among competing firms.
By designing out waste now construction projects can meet industry standards, such as the Code for Sustainable Homes, but it can also attract new clients with an interest in environmental issues. Working with clients and contractors to design out waste can also lead to cost savings and marketing opportunities for both designers and client. Programs like the Halving Waste to Landfill initiative set up by the Waste & Resources Action Programme (WRAP) have enabled firms to set waste reduction targets, identify opportunities for future developments by helping contractors identify areas where material wastage is common and measure potential improvement through quantified standards and targets.
In areas of China, rapid urbanisation has resulted in mountains of construction waste clogging sites
As the world around us changes, so to do the aims of each sector. With its physical impact on the environment and the financial significance to the international economy, the construction industry needs to stay at the forefront of change. By embracing sustainable techniques now, the industry can begin to integrate technology in a way that enhances the sector and improves the quality of life for everyone. Construction firms are switching on to a more environmentally responsible approach, but it’s a never ending process of evolution and adaptation. This is a fight the industry can not afford to back down on, much less lose.