Challenging perceptions for a zero-carbon future

Hand holding wooden house on green leaves background with copy space. Home ecology concept.

With the government setting its zero carbon emissions 2050 target, the construction sector is under increasing pressure to build in a more environmentally friendly way. Here, Chris Williams, MD of Green Life Buildings (GLB), discusses why perceptions of Expanded Polystyrene (EPS) and concrete must change if we are genuinely serious about cutting carbon – and how GLB’s Advanced Building System can play a vital role.

There’s no denying that the government’s 2050 zero carbon emissions target is a daunting task, but studies have shown that it is an attainable goal if we start now.

A zero carbon economy will have a much greater need for energy-efficient building materials and energy-efficient structures, which means the construction sector has huge opportunities over the short and long term to reduce carbon emissions.

But perceptions of those materials need to be challenged to give us the best chance of hitting the target, none more so than when it comes to Expanded Polystyrene (EPS) and concrete.

Changing perceptions

We are a herd species, and most of the time we don’t have the patience to unlearn preconceptions and prejudices.

There is a perception that Expanded Polystyrene (EPS) and concrete have a negative impact on the environment. But polystyrene has been recognised as the insulation product with the lowest environmental impact (www.sciencedirect.com/science/article/abs/pii/S036013231400393X) and concrete is the lowest CO2 structural building product you can get. (www.giatecscientific.com/education/defending-concrete-most-sustainable-construction-material/)

While concrete might raise an eyebrow, society and our industry do not fully understand CO2 figures and the embodied carbon content.

When someone says concrete is bad, what they really mean is cement – but on the whole, cement only makes up a fifth of the material that goes into concrete. Sand and gravel, the other key ingredients, have just 1g of CO2 per kg – not even timber is that good.

Results that speak for themselves

The GLB building system (using M2 technology) is a modular panel comprising two wire meshes made of galvanised welded steel, joined by connectors and enclosing an expanded polystyrene sheet. These are then assembled and sprayed with shotcrete on site to complete the structure.

The rigid panel is more than 90% air, providing the best carbon footprint per U value, while just 80mm of our low carbon concrete provides a structural wall with a carbon footprint of only 33kg/m2.

When you consider that a brick/block wall insulated to the same U value with mineral wool would be 177kg/m2, the difference is huge – and each home built using the GLB system could save 40 tonnes of carbon.

The home can also reduce energy expenditure and carbon emissions by 65% compared to traditional builds, where the thickness of the EPS can be increased, but still be slimmer than a traditional cavity wall.

The time is now

Our sector is under increasing pressure to provide affordable materials that produce top quality construction with less impact on our environment.

To achieve this, we must integrate the fabric of the building with its use, and help the industry transition to modern heating, lighting systems, renewable power systems and localised waste management.

The GLB building system is lightweight, but has a compression strength of at least 10 times that of a breezeblock, and integrates metal lattices throughout the insulation. That means that instead of insulation being an add on, it provides tensile strength and means less concrete (and cement) is needed.

The design and combination of the three materials is why it works so effectively – and why the GLB building system can be even better than using wood based products if we are genuinely serious about cutting carbon. (https://www.giatecscientific.com/education/defending-concrete-most-sustainable-construction-material/)

We already know how to make a zero-carbon home, and moving forward, buildings should not be costing the earth – literally and figuratively. But to achieve that, we need designers and specifiers to understand what is already capable.

For more information on Green Life Buildings visit www.greenlifebuildings.co.uk