How polished concrete is lighting up the sustainability world - literally!!
Innovative techniques and technologies in the flooring and construction world have transformed the way we view the humble concrete slab. Gone are the days when we would strive to cover and hide the drab ol’ concrete slab with carpet that made you feel you were on psychedelics or, god forbid, toxin-laden plastic lino, or even worse - slaying our beautiful forests and trees for floor boards!! Now, gratefully, for the health of ourselves and the environment, it’s the concrete’s time to shine, quite literally [pun intended]!! Concrete polishing has opened up a new world of possibilities in construction and renovation. At a time when the world is screaming for sustainability and longevity at the forefront of decisions, concrete polishing has stepped up to the plate and is delivering. Let us show you how!
Grab a cuppa and settle in, it's as comprehensive as it is important, and well worth the read.
How is polished concrete classed as sustainable?
I hear you. Isn't concrete one of the high-emitting culprits of CO2? Well, yes, however it’s mainly due to the amount of cement used in its production. Chemical and thermal combustion processes used in the creation of cement produce high CO2 emissions, and with more than 4 billion tonnes of cement produced worldwide each year, it contributes a significant 8% to global CO2 emissions (1). For this reason, cement production techniques and concrete material alternatives are on the radar for those innovators seeking to address greenhouse gas emissions, and later we will cover some of the more simple techniques that are available to anyone, (you don't have to be a mad scientist or engineer to make a difference!). However, cement remains a vital material in the construction and building industry so we will be focusing on understanding the main environmental benefits of polishing concrete, and ensuring what we have available to us, what is under our control, is as eco-friendly as we can. If you're keen to go green in your buildings, read on.
Sustainable Flooring Solutions: Polished Concrete
Lucky for us, polishing concrete, especially already existing slabs, has a myriad of benefits for both us and the environment. Let's take a closer look at some of the reasons polished concrete gets so many gold (or green) stars.
Thermomass properties:
A large percentage of energy (40%) in the average Australian home is used for heating and cooling, however this can be significantly alleviated by using passive house design principles, which play an important role in sustainable and comfortable housing (2). Enter: Polished concrete! Literally, pretty much a powerhouse - hear me out.
One of the best features of polished concrete is its high thermomass/long thermo lag properties. Thermomass is the ability of a material to store, absorb and release energy in the form of heat (3), and concrete is really clever at this, IF the house design has been equally clever. Thermomass is only effective when passive design principles which improve the thermal performance of a building are considered. If your climate generally needs cooling in summer or heating in winter, a high thermal mass material can help reduce these costs by passively providing temperature control. For example, orienting your building to face north with purposely designed windows and eaves to allow sunlight to hit the concrete floor directly, has benefits for passive heating and cooling, which will save loads of electricity, and money, in the future. A win for people and the planet. How does this work? Because of concrete's long thermal lag properties, which is the time it takes to release the heat energy that has been captured from direct sunlight during the day, and slowly releasing it during the night. A concrete floor will retain heat longer than a material such as wood which has low thermal mass/fast thermal lag. The operable word here is DIRECT, this will ONLY work if the sunlight hits the bare concrete directly, you can't go covering your concrete foundations with carpet, vinyl or wood and expect passive heating/cooling to work. Plus, that's just an unnecessary double up on resource usage, use what you already have - concrete, just waiting to reach its full potential! And, yes, this works in reverse for cooling, for summer months you would ensure the concrete does not receive direct sunlight, allowing the concrete thermal lag to retain the coolness from overnight temperatures and keep the building cooler the next day. Put simply, it averages out day/night temperatures.
Of course, this is just one element of passive design, and in order for it to work effectively, it must be used in conjunction with other principles, ‘the whole is greater than the sum of its parts’ (Aristotle's wise words). If planning to build, renovate or extend, contacting a NatHERS assessor who measure and rate a home's energy efficiency, may help to assess your particular needs, alternatively Your Home: Australia's Guide to Environmentally Sustainable Homes, is a great resource, and of course, engaging with builders who are sustainability design focussed.
The above thermal mass discussion focussed on residential homes, however commercial and industrial buildings would achieve similar, if not more benefits, especially in the energy saved from heating and cooling. You can expect that all the benefits of polished concrete mentioned in this article would be magnified 10-100x for commercial and industrial spaces! However, I'll write another article with specifics for this topic. [link]
Energy saver:
In addition to the massive potential energy savings from its thermomass properties (above), the reflective nature of polished concrete also contributes to reducing your buildings energy consumption, and your hard earned cash. Reflecting natural light during the day reduces reliance on artificial lighting, and at night, reflections support using less lights in total. Lighting uses approximately 5% of average Australian home energy consumption (2), and 30-50% in commercial buildings (4), therefore this property of polished concrete, can be quite significant in some circumstances. ‘Daylighting’ is a term used to describe the active use of daylight for building illumination (4), and its benefits extend further from saving energy. Our health and wellbeing are also massively supported. Studies have shown increased illumination via natural light in buildings can reduce headaches, relieve eye strain, improve mood and wellbeing, reduce depression and anxiety, increase vitality, support a coherent circadian rhythm, increase immune function, and maintain our natural inherent yearn to feel connected to nature. This has also been recognised in hospital design, as increasing access to windows and daylight can improve healing (4). Any benefit that supports human health and wellbeing is significant in my opinion, and this list is just a summary. I agree with some experts that suggest if more emphasis were placed on the health and psychological benefits of daylighting, this topic might resonate more strongly, in addition to or surpassing the energy savings benefit on its own (4). With up to 80% of our life spent indoors, it's a big deal! One might argue an easy solution would just to get outside more often, and yes, i agree more time outside would be ideal, but not everyone can due to various reasons (work commitments, climate, illness, mobility, elderly), so my statement remains - its a big deal!
What's more romantic though, is actually the ambience! The way light dances around a room, reflecting and bouncing the stories of your home, office/showroom or commercial space, creating beautiful splashes of colour, timeless elegance and style, illuminating the endless possibilities of reality. A built in statement piece, yet transformational mirroring the eb and flow; day- night, light-dark. Dreamy right?! So if aesthetics is more your jam, this point was for you. Well, actually, it's really for everyone. I'd argue a beautiful well designed aesthetically pleasing space increases positivity, boosts morale and productivity and creativity would overflow from a space that is designed with these dreamy characteristics in mind. Who wouldn't love to be in a room like that? No-one likes working in a gloomy dark office space!
Hypoallergenic
[To be continued … Rome wasn't built in a day!]
References
Lehne, J. and Preston, F. Making Concrete Change Innovation in Low-carbon Cement and Concrete, Chatham House Report. Accessed March 2024. https://www.chathamhouse.org/sites/default/files/publications/research/2018-06-13-making-concrete-change-cement-lehne-preston.pdf
Your Home: Australia's Guide to Environmentally Sustainable Homes. Heating and Cooling. Australian Government. Accessed March 2024. https://www.yourhome.gov.au/energy/heating-and-cooling
Your Home: Australia's Guide to Environmentally Sustainable Homes. Thermal Mass. Australian Government. Accessed March 2024. https://www.yourhome.gov.au/passive-design/thermal-mass
Mohamed Boubekri, Introduction, Editor(s): Mohamed Boubekri, Daylighting, Architecture and Health, Architectural Press, 2008, Pages 1-8, ISBN 9780750667241, https://doi.org/10.1016/B978-0-7506-6724-1.00025-7. (https://www.sciencedirect.com/science/article/pii/B9780750667241000257)