University interns deliver sustainable added value back into the construction sector

Here at Build Test Solutions, we remain mindful of our academic roots – our young sustainability-led company was born out of academic research and as we head rapidly towards our 10th year, we have been enjoying the opportunity to be able to feed something back.

We have recently engaged 2 undergraduate students from Loughborough University to carry out a research project which will provide valuable insights into the benefit of adding measurements to EPCs, to include a sensitivity analysis of rdSAP/SAP lookup values versus known measured parameters such as airtightness, U-values and HTCs.

Why must EPCs be made more accurate?

Energy Performance Certificates (EPCs) are the UK’s main method to assess and rank the energy efficiency of buildings. They are used widely for important processes like allowing homes to be compared when up for sale or letting, allocating government-funded retrofit activities, evaluating the success of retrofit projects, and assessing fuel poverty levels.

EPCs are generated using a standardised energy model (called the Standard Assessment Procedure, SAP) to assess a building's heat loss characteristics, model the heating system's efficiency, and calculate annual energy consumption, cost, and associated emissions given typical weather and occupant behaviour. The headline EPC rating is then based on the total energy cost of operating the home.

SAP includes lots of inputs that are difficult to determine by a visual survey, so there is a simplified version of the inputs called Reduced Data SAP (rdSAP) which allows more practical surveying but makes estimates on factors affecting the building’s energy performance like the heat loss through walls, floors, roofs, windows and doors or how draughty they are (technically defined by the U-value for heat loss and airtightness for draughts).

At BTS we manufacture products to measure heat loss and airtightness in situ to give a more accurate understanding of the energy efficiency of buildings. These measurements can then be used as inputs to the SAP or rdSAP calculations to calibrate the EPC to be more accurate.

The project being carried out by our interns is a sensitivity analysis to understand how impactful these measured inputs could be, determining their effect on predicted energy consumption, cost, emissions, and EPC ratings. The results will be used to demonstrate the value of performance measurements to better inform building assessment, this will apply to the UK specifically but also has relevance to many countries which use a similar energy modelling approaches. BTS will use the results to publicise the value of measurement and why they are so important in helping to better target investment and in verifying the quality and performance of what gets built or installed.

Project phases

The initial phase of the project has seen the definition of a set of building archetypes. There are around 15-20 archetypes identified which are considered to give a sufficiently representative view of the UK housing stock.

The second phase has been to identify and validate a SAP 10.2 tool which will then be used to model each archetype. The following parameters will then be adjusted in each model with a low, central (standard RDSAP lookup) and high variant:

• Floor U-value
• Main external wall U-value
• Roof U-value
• Air permeability/airtightness
• HTC

With this main sensitivity analysis is complete, the students will look at the impact of adjusting various combinations of the above parameters. We will also then look at what the findings might mean for the housing stock on a national level by mapping the results to EPC Open Data.

What was the driver behind the project?

Aside from having a fresh set of data to further validate the innovative products being continuously developed by BTS, it also gives the team a chance to nurture the next generation of engineers and data analysts.

Indeed, our recent article on green careers maps out that need and current skills shortage in more depth.

It also provides students with real-world experience of not only using data in their day-to-day careers, but also experiencing a real-world office environment. Ever since the Covid pandemic, many students have missed the chance to gain these vital soft life skills. This may well have an impact for a much longer time span on their careers than mildly affected exam results may do, for example.

Build Test Solutions hopes to be able to give at least a small handful of future industry peers the right building blocks to start to forge their career paths.

How did the students find working with Build Test Solutions?

Both students found the chance to apply university-taught skills to something tangible in the real world an exciting and motivating experience. They also improved their skills by enhancing existing knowledge with more advanced and specialised methods, such as VBA, while working with much larger data sets than previously.

Says Tom Kerrison, 3rd year Mechanical Engineering undergraduate,

"Being involved in a role where the impact is clearly visible, not only just for Build Test Solutions but also for the public, is highly fulfilling. Additionally, seeing the passion and enthusiasm the Build Test Solutions team display towards the value and benefits that improved measurement techniques can have, is both inspiring and motivating."

Additionally, Aaditiya Saheta, a 3rd year Chemical Engineering undergraduate, went on to explain,

"This internship has been a great opportunity to apply my chemical engineering knowledge to real-world energy efficiency challenges. Working on sensitivity analysis has deepened my understanding of process optimisation and how small parameter changes impact CO2 emissions, costs, and efficiency. The role has also been a great challenge, pushing me to refine my analytical skills, particularly in handling large datasets using Excel and VBA. The team has been incredibly welcoming, fostering an environment where I can ask questions, continuously improve, and grow both technically and professionally."

What was the outcome?

The results will be published later this year. For now, you can learn more about the products we have already developed and successfully brought to market.

Got a question about the work and research we are doing?

Feel free to contact us!