Many of the causes of climate change are beyond the scope of building design but changing the way we procure, design and construct buildings shouldn’t be – and the hard truth is the built environment has failed on embedding sustainability for too long, writes Chris Halligan MCIAT CEnv
The last three years has seen the average global temperature exceed 1.5C, which was the threshold governments promised to avoid under the 2015 Paris Climate Agreement. A high emissions scenario is now far more likely and, if so, we will be lucky to keep the global temperature increase to under 4.5C by the end of the century. Such an increase actually threatens human survival.
So after 20-odd years of our regulations supposedly driving us further towards sustainable outcomes, in reality we’ve failed – and we are continuing to fail. Why?
In pre-industrial times, buildings would be constructed largely from local materials and would have to exploit the available benefits of the local climate [See Image 1].
This gave rise to a huge variety of building forms which would have to be capable of being used within their respective climates. However, with industrialisation, we seem to have arrived at solutions that differ little from each other, no matter which part of the world they are in.
Furthermore, instead of the buildings themselves being designed to harmonise with the environment, we depend on engineers to condition their interiors by technological add-ons. These technological solutions are often assessed in isolation without taking into account sustainability as a whole.
Our technological mindset drives us to seek “magic bullets” such as electric vehicles, hydrogen fuel and artificial intelligence, which we hope will solve the climate emergency but in many cases seem to make matters worse.
However, the natural environment is very complicated. There are no simple answers – especially if we choose to only address isolated elements of it. [See Image 2]
I would contend that we aren’t actually addressing the causes. Instead, we are trying to find “workarounds” that don’t interfere too much with our present social and economic activities. Even the concept of “net zero” is only aimed one aspect of sustainability – operational carbon – when there are many other issues of equal importance impacting on the environment.
A short-sighted approach
If we look at a pyramid diagram, we see a path from inception to completion, which starts with looking at the site before any ideas of design are even considered [See Image 3].
We can see how we move through the design process to creating the fabric and performance in use. Then (and only then) should we introduce renewables to meet the resultant reduced load.
But what we do at the moment is to effectively ignore the first three tiers and expect the last two to sort it all out.
This rather short-sighted approach often leads to unforeseen consequences – such as internal overheating, which is becoming a noticeable issue in buildings.
The overheating of new housing is partially driven (ironically) by an attempt to be more sustainable. Recent planning legislation changes have demanded higher densities of site use, which has led to three- and four-storey dwellings becoming more common. This density impacts on the building’s ability to dissipate heat.
In addition, with the move towards “room-in-the-roof” designs, these top storeys will be more prone to overheating due to their thermally lightweight construction.
Even renewable energy solutions are presenting unforeseen problems. By 2050, it is estimated that there will be 60m tonnes of waste photovoltaic panels globally. These, like any composite material, aren’t easily recycled, so will eventually be part of the problem rather than the solution. Yet UK Building Regulations drive you toward PVs to comply with the minimum standard.
Design principles ignored
There are fundamental principles of design which, if applied properly, can have a substantial impact on both the comfort and energy requirements of a building. These include:
- Density of fabric (thermal mass).
- Proportion of wall glazed.
- Depth and height of spaces.
- Type of glazing.
- Orientation.
- Location.
- Access to daylight.
These considerations are often just ignored for one of many different reasons. Examples include:
- Maximised floorspace.
- Saleability.
- Public façade.
- “Signature” designs.
- Whatever is easiest or cheapest!
But the truth is that the environment is very rarely accurately quantified in our projects.
At present, our economics don’t take into account the cost of our activities to the environment – in money or anything else.
This doesn’t mean those costs don’t exist. They do – but are largely just ignored until someone else deals with them. The latest highly publicised example are the California wildfires, which are estimated to have cost $250bn. This in a country where every mention of climate change has been eradicated from government media.
Environmental disasters are occurring with increasing frequency and their economic impact has risen by over 150% in 20 years, costing the world more than £95bn in 2025 alone.
Before the middle of the 19th century, these aspects were considered essential design constraints of architecture.
The only technologies available were often coal fires or opening windows. So it was essential to take into account the free heating or cooling provided by the local climate.
With the advent of industry and technological solutions, these considerations could be forgotten and the interior environment of buildings left to engineers to deal with – usually by machinery using fossil fuels. Architects have progressively largely abandoned responsibility for the way a building might respond to the natural climate.
We need to reapply these principles and start considering the form and fabric of the building as being an environmental modifier in its own right.
Many of the causes of climate change are beyond the scope of building design but changing the way we procure, design and construct buildings shouldn’t be.
The only shortcoming is in the intention and willpower to consider basic design principles, combined with sustainability as a constraint.
It shouldn’t be difficult or unusual.
The design team needs to be integrated from the earliest stage with sustainability considered (and championed by an appropriate professional) as part of good design, just as any other function or constraint.
It shouldn’t be an option.
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