Sustainable building design in the education sector
Managing Director of Langley Eco Solutions, Keith Hills reveals the keys considerations leaders and decision makers in the education sector should think about when designing a green roof for their facility.
Across the country, we’re witnessing a green revolution. Developers, local authorities and end-consumers alike are beginning to see the impact they can make on our collective journey to decarbonisation.
There are an increasing number of legislative changes aimed at creating a more sustainable future, for all areas of the built environment. In its Heat and Buildings Strategy, for example, the Government outlined its plans to decarbonise all sectors of the economy by 2050.
In the minds of those responsible for ensuring educational settings are delivering the very best they can for students, educators and wider building users, it’s becoming more important than ever to consider the green infrastructure of a site – to hit net zero goals and meet wellbeing needs.
For educators and their facility teams, though, the benefits to be gained from leaning into the green envelope, extend far beyond a mere tick box exercise or adherence to legislation. Roofs especially are one of the most underutilised spaces on any estate and one of the first that educators should be looking to retrofit.
Look up – making use of roof space
A green, blue and/or solar roof is a great place to start for any educational facility. When installed and maintained with expertise, an eco-roof maximises previously underutilised space and can be tailored to the needs of an individual institution.
Due to the living components of green roofs, expertise in design, installation and maintenance of the system is crucial to the success and longevity of the roof. From the get-go, it’s important for estate management and designers to consider the intricacies of the space they’re dealing with before agreeing an approach.
If the roof is going to be a used space, such as an additional classroom or outdoor facility, accessibility for users and maintenance teams needs to be built in from the start. Green roofs can provide an invaluable space for learning outside the classroom, with some schools going as far as turning their roofs into playgrounds or urban gardens.
For some, this won’t be possible. In which case, even where the structure or layout of the building does not support the creation of an accessible green roof, the installation of a biodiverse roof will deliver on many other levels and benefit students by enriching their green surroundings. Organisations such as the Wildlife Trust highlight evidence that wildlife-rich environments benefit both physical and mental health – even if we’re only looking at them.
Identify the full potential
Indeed, contact with and proximity to nature has been shown to reduce stress and improve mental health and wellbeing. Wellbeing alone should be good enough reason to install a green roof, green wall or create a newly landscaped garden space, but there are a great deal more reasons to retrofit.
Firstly, choosing a green roof helps to improve a building’s energy performance. The thermal properties of a living room helps reduce the Urban Heat Island (UHI) effect of buildings in towns and cities which contributes to global warming and occurs when materials such as concrete, masonry and asphalt absorb then store heat from the sun. This increases overall temperatures in urban areas – even at night – and places greater demand on building cooling. By regulating the building in all weathers, adding vegetation to a building helps to improve its energy efficiency.
Increasing the quantity of vegetation on an estate can also vastly improve its air quality. Plants help to filter harmful gases out of the air while the vegetation helps to capture particulate pollution which is then washed into the soil by rain, where it is broken down.
Think holistically to boost eco credentials
As well as thinking green, think blue. A blue roof system, engineered to store rainwater and release it in a controlled way to limit the impact of heavy rain, can be used as a source-control measure in a Sustainable Drainage System (SuDS) strategy.
When heavy rain falls on hard, impermeable surfaces it quickly runs off into drains, which can become overwhelmed, leading to flooding. Alongside the inconvenience of having a flooded and unusable playground or carpark, for example, localised flooding can also damage the estate. With the occurrence of extreme weather becoming more frequent, effective water management is a growing priority, particularly in urban environments.
Fortunately, the water trapping qualities of a blue roof system can reduce the quantity and speed of rainfall from the roof and provide opportunities for evapotranspiration. The capacity and effectiveness of a green roof in managing rainwater will depend on factors such as the type and composition of the system, the depth of the substrate and the moisture already in the soil. Research has found that extensive green roofs can intercept 50% of annual rainfall while intensive roofs with deeper substrates can intercept up to 90% of the rainfall.
Not only does a blue roof help protect a building through better water management, it can also significantly reduce the noise of rainwater in the classroom, promoting better concentration and contributing to improved wellbeing among students and staff.
Adding solar panels – BioSolar design – will further bolster the eco-credentials of your building and the long-term impact of your retrofit will be felt in the noticeable savings due to improved energy efficiency. While nothing new, our understanding of how to harness their power has moved on considerably over the decades. So much so that we now understand that by fitting them alongside a green roof, we reduce the historic tendency to overheat and maximise their energy generation potential.
Green roofs are broadly divided into two main types: intensive and extensive. The intensive and extensive labelling of an eco-roof relates to its desired purpose, and typically indicates the level of maintenance required.
Intensive green roofs – roof gardens and podiums – typically require much greater care to preserve the inherent biodiversity they contain in an effort not to be overtaken by invasive species. As they are visually and naturally distinct, they will require more upkeep, especially if it’s a space used day to day. Crucially, intensive roofs must prioritise aesthetics. If a lawn has been installed, for example, it must remain as one and not become overgrown.
Extensive green roofs which include biodiverse roofs – comprising hardier plant life – are typically lower maintenance, with only bi-annual or quarterly maintenance needed. That said, it is still recommended that only those with a LANTRA qualification are brought on board to maintain the roof to enhance biodiversity and to ensure the living roof remains compliant as the roof develops.
The design has to be feasible, with drainage and maintenance pathways considered, as well as practicality in the long-term factored in. Chosen plant species should also be carefully considered and matched against the natural surroundings in the local area. While all plants will need the right maintenance to survive, non-native species are less likely to thrive, and therefore more likely to die and create a fire hazard. Regular maintenance by a trained professional will ensure that your roof remains both safe and at its best.
Transforming education estates will play a key role in achieving the UK’s decarbonising goals. While space is at a premium, eco solutions are an excellent way of maximising under-used spaces while also helping estates to meet net zero and improve their efficiency levels at the same time.