Retrofitting non-domestic property: it takes more than a few solar panels

Catriona Jordan
Catriona Jordan

80% of the buildings that we’ll use in 2050 – the UK’s target for achieving net-zero – have already been built. Reducing the energy requirement of these buildings is a key step in the transition to zero carbon. Caitriona Jordan, head of retrofit programmes at Construction Scotland Innovation Centre (CSIC), looks at how. 

There are an estimated two million non-domestic buildings in the UK, from schools and universities to hospitals, factories, and offices. Yet, while used by different people for different purposes, the latest figures from The Climate Change Committee revealed that buildings were collectively responsible for around 17% of the UK’s greenhouse gas emissions in 2019.

Reducing the energy requirement of these buildings is a key step in the transition to zero carbon. 80% of the buildings that we’ll use in 2050 – the UK’s target for achieving net-zero – have already been built.

An effective retrofit strategy involves a considered, logical approach and while additional technology such as solar panels can help, it runs much deeper than that. In practice, we have to look at the thermal properties of a building with the ultimate goal of reducing energy consumption. That in itself could be a big challenge depending on the size of a development, but an initial retrofit assessment of the levels of insulation and airtightness would give a starting point for an action plan.

Another approach is the globally-recognised EnerPHit standard – the equivalent to Passivhaus for highly energy-efficient retrofit projects. As part of the process, a specific set of criteria must be met and assessed, such as space heating and cooling demand, and the inclusion of a mechanical ventilation with heat recovery system (MVHR). Buildings that meet the EnerPhit standard can achieve energy savings of between 75-90%.

Skills gap

There is a widely reported skills gap across many areas of the construction sector – particularly when it comes to the types of roles needed to achieve zero carbon – and retrofit is no different. In Scotland, for example, we are only aware of a handful of architectural firms that have experience in EnerPhit retrofit for non-domestic properties. To deliver the scale of change that is needed, we will also need to focus on upskilling and training people to become retrofit coordinators and assessors, as well as other key roles.

Unfortunately, we have to recognise that retrofitting commercial property may not be as straightforward as retrofitting homes. There will be a range of different considerations for the various types of buildings that can make projects more complex and more expensive. For instance, a school would need to think about the level of disruption to learning, and a hospital has complex challenges such as infection control. 

Solar Panels

That said, there are a number of projects that are starting to show us how it can be done. St Sophia’s Primary School in East Ayrshire, is set to become the UK’s first EnerPHit school later this year, paving the way for similar projects in the education sector in the future.

Timber-based kit-of-parts

Construction Scotland Innovation Centre is working with Transport Scotland on the NearHome project to deliver a timber-based kit-of-parts that can be used to transform unused public buildings into environmentally-friendly office hubs. The next phase of the project involves the creation of a demonstrator unit, with a design that can be adapted for different sizes and types of buildings.

For offices, in particular, new hybrid working patterns mean that companies need to do more to encourage employees to come to work. The working environment plays a big factor in that, and there is a growing trend for workplace design that is centred around sustainability, wellness, and biophilic design – making the most of the natural environment.

It still seems that many decisions around significant CapEx projects, such as retrofitting buildings, come down to cost, and so the role of procurement is also a critical piece of the puzzle. With a climate emergency upon us, it is time to start thinking of a building’s cost in terms of carbon emissions over its entire life cycle, rather than just the financial investment. While there are no quick fixes, with a step-by-step approach to retrofit we can accelerate the reduction of the built environment’s carbon footprint.

Caitriona Jordan is head of retrofit programmes at Construction Scotland Innovation Centre (CSIC)

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