Mike Vaczi from Soprema UK discusses how applying circular economy principles in roofing specification can help achieve net zero
As part of the UK Government’s 2021 strategy to achieve net zero in the built environment (meaning the amount of carbon emissions associated with a building’s usage and construction stages must equal zero or negative), working to achieve this in roofing has become a top priority for specifiers as well as suppliers.
The importance of early engagement with supply chains during building design has never been so important, especially when developing ethical and sustainable specifications to incorporate a Cradle-to-Cradle (C2C) strategy.
C2C unites many principles beyond simple material reuse – these include everything from safe sourcing to renewable energy usage and social fairness. But how can architects and specifiers apply this thinking when it comes to flat roofing design?
Product selection
Thinking differently about products during roofing specification, and working collaboratively with the supply chain, can pay dividends when trying to achieve sustainability goals. Working closely with an experienced and accredited manufacturer from the outset and selecting the most suitable materials for the roofing project, is paramount.
In the mission to achieve greener credentials, it’s advisable to seek out manufacturers with cradle-to-cradle certifications which recognise their products worldwide, as part of responsible purchasing. For example, one of our membranes has been awarded a bronze certificate by the Cradle-to-Cradle Products Innovation Institute, following a series of thorough investigations by a jury. Five specific performance categories are considered; material health, product circularity, clean air and climate protection, water and soil stewardship, and social fairness.
Early engagement with supply chains will ensure the best ethical and environmental specifications are developed, while also creating a robust and durable solution. During the design stage, roofing material characteristics, qualities and build-up all impact sustainability goals.
Bituminous membranes
Bituminous flat roofing products are available that fit the bill when it comes to cradle-to-cradle specification. One BBA, Broof and EN certified membrane solution consists of a double bitumen coating with fire-retardant additives and a composite polyester reinforcement. The plastomer modified bitumen (TPO) upper side has a high mechanical resistance and is UV-resistant, while the elastomer modified bitumen lower side and the overlap ensures excellent adhesion.
Products like this are often specified in roofing as an upper layer within a single or multi-layer waterproofing system, where fire retardant properties are required. In some cases, the upper surface is finished with granules and the overlap and lower surface are protected by a ‘thermofusible’ film.
Quality specification
But it’s not just certifications that architects need to look out for to help improve sustainability. C2C accreditations, for example, are just one element of a broader framework of efforts that manufacturers should undertake.
When it comes to responsible sourcing, using products made from recycled materials, such as insulation from recycled polystyrene, is also important. In addition, some manufacturers offer ‘natural’ insulation materials – such as Pavatex, which is made from wood residues from sawmills. Also, old bitumen roofing membranes can be recycled into new roofing products and asphalt for use
on roads.
Manufacturers should be looking at the wider impact of their materials on the health of other organisms, too, ensuring they does not contain hazardous chemicals such as heavy metals. Of course, this is not achievable with all products, but bituminous membrane solutions for flat roofing design for one do comply.
During design stages, architects should also consider the product’s circularity; is it reusable, and can it be part of a ‘closed chain’? Product manufacturers need to provide information on how much CO2 their products emit through the production process, as well as the company’s commitment to clean air policies. Water consumption during manufacture is also a key factor in achieving C2C standards.
Employee working conditions and wellbeing also contribute to sustainability goals – which is perhaps surprising to some. In addition, manufacturers’ relationships with customers, suppliers and employees should be characterised by integrity and respect. Being responsible for all aspects of safety regulations in everything they do, while providing workplace opportunities for employees to grow and excel, creates a happy and inspired workforce. This ultimately delivers better customer service.
A greener outlook
When specifying products, aside from the appropriate C2C accreditations, BBA approvals and adherence to mandatory testing, it’s also advisable for specifiers to look outside the box and consider the manufacturer’s business as a whole when adhering to circular economy principles. For example, we are a member of the Liquid Roofing and Waterproofing Association (LRWA) which holds extremely strict membership criteria. Specifiers can thereby ensure that the highest standards are continually being met within roofing and the wider construction industry.
Sustainability has been a hot topic for some time, but its importance is only going to grow. With the target to achieve net zero in carbon emissions by 2050 outlined last year, partnering with an experienced and trusted manufacturer is one step that specifiers can take towards a sound and sustainable product selection, which will benefit the building landscape for many years to come.
Mike Vaczi is technical manager from Soprema UK