As developers, designers and planners seek to go beyond simple compliance with environmental regulations and create truly sustainable buildings, the concept of Net Zero Carbon buildings has grown in popularity. Now, however, many are beginning to wonder if ‘Zero’ goes far enough and are looking to not only eliminate their negative impact, but to do more good, and create a positive impact – leading to the concept of Net Positive buildings.
The European Commission’s definition of Net Positive buildings focuses exclusively on energy, referring to a building that “on average over the year produces more energy from renewable energy sources than it imports from external sources.” Other definitions of Net Positive go beyond energy performance, and the most widely accepted idea is that Net Positive is an approach to development where more is put back into society than is taken out.
This approach goes beyond Net Zero to focus on making a positive difference, meaning that the new development creates greater net environmental and social gains than would be achieved from not constructing anything on the site. Net Positive buildings can be summarised as those that generate more value (in environmental and socio-economic terms) than they need to fulfill their own need.
Both Net Zero and Net Positive buildings require a reduction of building energy consumption and compensation for carbon emissions through on-site generation or certified offsetting schemes. Projects may choose to focus on the construction phase, operation phase, or, ideally, the whole lifecycle of the building encompassing construction, operation, maintenance, and eventual demolition.
Although Net Zero typically focuses on carbon and energy consumption, Net Positive buildings go beyond this and take a more holistic approach encompassing factors such as biodiversity, education, well-being and skills development which add value for users, occupants, and wider society. Additionally, Net Positive can be seen as a more systems-based approach where the performance and benefits associated with several buildings are linked, encouraging collaboration and cooperation between nearby projects. A key issue in Net Positive design is how new buildings contribute and fit into the local area and existing building stock.
Recommendations for achieving a Net Positive building suggest that reductions in energy demand and on-site renewable generation should be prioritised. Urban greening projects can support the achievement of these reductions by offering insulating properties and absorption of carbon emissions, as well as deliver further environmental and socio-economic benefits. Inclusion of urban greening not only contributes to a net positive building but can also be a significant element in achieving biodiversity net gain for the development.
Urban greening such as living walls, micro forests, and LivingPillars™ help to minimise energy use throughout a building’s lifecycle, making both new-build and renovated buildings more efficient and comfortable, supporting efforts for Net Positive buildings. In fact, living walls can lower temperatures in summer and reduce energy costs by up to 23 percent. Internal living walls improve indoor air quality and the well-being of building occupants. Additionally, living walls also reduce temperature fluctuation at the wall’s surface, which can damage a building’s façade over time, reducing maintenance expenditure and pro-longing the building’s life. The Urban Heat Island effect is greatly reduced by shielding the building fabric from absorbing the sun’s rays.
Not only do living walls reduce energy consumption requirements for cooling but they also help to mitigate the urban heat island effect and reduce noise pollution. Urban greening installations like micro forests and living walls can also increase flood resilience, improve local air quality, improve people’s well-being and create habitats for local wildlife. The development, use, and maintenance of living walls and urban greenery also support Biodiversity Net Gain (BNG), ecological education and the development of skills for a sustainable future - all benefits which can be maximised when taking the systemic, holistic view of planning associated with the development of Net Positive buildings.
To learn more about innovative urban greening solutions and how they can help contribute to net positive buildings, please get in touch.