Sustainable House of the Future

Giovanni Patania is the Lead Architect & Co-Founder of WindsorPatania Architects. In this article, he discusses the four pillars of sustainable homes.

On reading recent pledges like the RIBA 2030 Climate Challenge and the UK government’s Green Deal, it’s clear that sustainability is no passing trend in construction and architecture.

We predict that years from now, property development will be all but unrecognisable due to the significant push for eco-friendly and sustainable housing. Developers, architects and other professionals need to offer sustainable solutions by default and actively encourage clients to develop homes that are better for the environment.

That means going a little further than just following basic advice on saving electricity and retaining heat. These tips shouldn’t be ignored, but we want to look at environmental sustainability on a larger scale and think about designing and creating the sustainable house of the future.  

So, what does that mean? Read on to find out, and we hope you’ll agree with us that making buildings sustainable can be an exciting opportunity.

Sustainable house design (Image: WindsorPatania Architects project´s library)

What is the RIBA 2030 Climate Challenge?

In 2019, The Royal Institute of British Architects (RIBA), the professional body dedicated to upholding standards in the architectural industry, set some ambitious yet achievable challenges for the sector over the next decade.

RIBA’s 2030 Climate Challenge is a set of guidelines to support architects moving towards sustainable house design and construction and enable the sector to contribute to the UK government's call for a 2050 net-zero greenhouse gas emission target.     

It’s underpinned by four pillars – operational energy, health and wellbeing, potable water, and embodied carbon – so let’s take a look at each of them.

Four pillars for the sustainable house of the future

Sustainable house design (Image: WindsorPatania Architects project library)

1. Operational energy: Using the environment to power our homes

The energy used to run and power buildings is referred to as “operational energy”, and reducing it is RIBA’s first pillar for sustainable design.

Often, homeowners think of the small steps they can take, like switching to energy-efficient light bulbs, installing smart meters and keeping doors shut to retain heat. Architects, however, should be thinking much bigger and considering how design can shape a building’s use of power.

Last year was a huge one for solar panels in the UK, with 36% more new solar capacity installed than in 2020. As technological advances are improving the efficiency of solar panels, we wouldn’t be surprised if they become the primary energy source for the sustainable house of the future – not least because any excess energy from them can even be used to charge a car or electric bike.

Aside from the environmental perks, there is much evidence that solar energy can also make economic sense. With fitting solar panels generally costing around £6,000 to £7,000 for the average home and energy savings of up to £800 a year achievable, the outlay could be repaid well within a decade. This is before we consider the much-talked-of rises in energy prices expected in the coming months and years.

Solar-panelled roof sample (Image: Green Match library)

But architects can make use of the sun in other ways, too. For example, it’s also possible to optimise solar energy gains by the exterior walls’ surfaces, exposing them to solar radiation and transferring this heat to the interior. Considering our relatively cold Northern European climate, it makes sense to squeeze everything we can out of the sun.

We can look even further north for inspiration on another renewable energy idea – harnessing thermal energy from the Earth’s surface. This is a practice in Nordic nations, most notably Iceland.

In contrast to the summer and winter extremes of the ambient air above ground, the Earth maintains a near-constant temperature just a few metres below the surface.

It is possible to use this geothermal energy by implementing ground source heat pumps. Choosing geothermal heating and cooling technology can remarkably reduce non-renewable energy dependency.

2. Health and wellbeing: The impact of biophilic design on our life

Secondly, let’s not underestimate the importance of our health and wellbeing, something addressed by RIBA’s second pillar.

Homes that connect with nature, also referred to as biophilic design, have been shown to reduce stress and anxiety while improving our mood and increasing our creativity.

One example of biophilic design is ensuring that our homes receive plenty of natural sunlight. Why? Because sunlight releases dopamine in the brain, which in turn is responsible for lifting our mood. Of course, maximising sunlight has energy-saving qualities, too, as the previous pillar addressed.

When designing houses, it’s even worth tracking the sun’s path to guide decisions on how the property can receive adequate light in all seasons.

Use of natural light and plants in interior design (Image: Unsplash.com library)

Don’t forget the importance of natural ventilation either.

The size, number and placement of vents can be optimised to provide a natural airflow through the building and bring moist and cool air into it in a controlled way. What an effortless yet effective strategy to enhance indoor air quality, especially in summer!

Finally, think about the visual experience of the sustainable house of the future, where interior design choices can create calming surroundings that enable inhabitants to feel connected with nature.

3. Potable water: The importance of water harvesting

One thing we do get plenty of in the UK is rain, so why not use it? Water management and potable water reduction are the next aspects, captured under the third pillar of RIBA’s targets.

There’s growing pressure on our national water supplies and drainage infrastructure, so future homes should reuse and recycle water as much as possible.

Rainwater harvesting is one of the most effective strategies to achieve this goal. It enables us to collect rainwater, store it, filtrate it and use it again for non-drinking purposes, such as bathing, showering, flushing the toilet, washing clothes and doing the dishes.

We should also make sustainability an essential principle while landscaping around our homes, which could incorporate rain gardens or permeable pavements, for example.

Rain gardens are sites that reduce the flow rate of polluted water, such as runoffs from roofs and driveways. They’re beautiful to look at, too, tying in with the previous pillar of health and wellbeing.

Permeable pavements, meanwhile, are made of more porous materials than classic asphalt, so they absorb water rather than allow it to accumulate on top.

4. Embodied carbon: How to measure the sustainability of construction materials

While the other three pillars are probably familiar concepts to people even outside of architecture and construction, RIBA’s fourth sustainability pillar might be less so.

What does “embodied carbon” mean?

We’re all familiar with the term “carbon footprint”, but we often only think of it in terms of how the finished product performs, and not how it was produced in the first place. For example, a car might have low carbon emissions, but how much carbon went into manufacturing it?

The construction industry uses the term “embodied carbon” to refer to the amount of carbon generated by the activities behind the construction process and the production and delivery of the materials that come together to create a building.

Each type of material, from brickwork to roof tiles, from steelwork to thermal insulation, has a specific value related to embodied carbon. This value depends on the energy needed for raw material extraction, refining processes, transportation, installation, and construction waste disposal.

Overall, buildings are responsible for 39% of global energy-related carbon emissions, and 80% of the buildings’ embodied carbon is from structural materials.

Use of recycled materials in interior design (Image: Unsplash.com library)

How can we reduce the “embodied carbon” of a building?

By carefully selecting materials and construction methods and using eco-friendly alternatives where possible, we can bring down the embodied carbon levels of a building. Here are three ways it can be done:

a) Select recycled materials

Metal is the big one to think about here. Recycled steel is considered a low-carbon option compared to using a virgin steel beam – not surprising, as the latter can have an embodied carbon volume of over five times greater.

b) Choose local products

Of course, this is often not only greener, but cheaper too. Forge relationships with local suppliers, rather than relying on essential items from other parts of the country or overseas.

c) Choose natural materials

Concrete is a significant contributor to embodied carbon. While ultra-low-carbon concrete blocks can be used for building interior and exterior walls, there are often greener and more sustainable alternatives. These include wood for flooring, and finishings and wood foam for thermal insulation.

As these alternatives become more popular, they are often offered at no additional cost, so price shouldn’t be a barrier to going greener.

Conclusion

Sustainable house design doesn’t have to compromise the quality of your builds, nor should it leave you out of pocket.  We hope that this overview has inspired you to be bold with your developments and think big about environmental sustainability.

The world is crying out for greener housing. By meeting this demand, you’ll not only get ahead of the curve, but you’ll likely also get into new and greener habits before RIBA’s recommendations become government legislation.

So, please don’t see sustainability targets as a burden. We encourage our fellow architects to actively put environmentally friendly design forward to clients and collaborators. We, for one, are excited to work with clients, builders and collaborators on sustainable design solutions, and start creating eco-friendly houses fit for the future.

If you liked this article and want to learn more about WindsorPatania Architects, please get in touch with us via our website: www.windsorpatania.com.