The urgency of the now: Why the UK needs better building performance measurement

When it comes to greenhouse gas emissions, it doesn’t help that the UK’s energy generation largely depends on fossil fuels. It has been that way for decades with about half of the country’s electrical power coming from natural gas and coal. While the more sensible choice would be renewable energy sources which cost significantly less, the government has yet to make a strong push towards that direction.

Instead, cash-strapped citizens are advised to manage their energy better with the hopes that less usage will mean less spending. The present energy crisis has led to a steep rise in the number of households in fuel poverty, many faced with not only cold and uncomfortable living conditions but many serious side effects ranging from higher incidences of condensation and mould, through to negative health and well-being effects.

It does not help that the UK has some of the worst insulation in Europe. Draughty houses mean that the poorest households are spending more of their income on heating their homes. Add rising inflation to the mix and it quickly becomes easy to understand why measuring and understanding the true energy performance of our homes and buildings is so critical. The numbers show that there has never been more urgency to tie up all loose ends. This involves not just the concern of whether houses have enough insulation but, more prominently, doing more measurement.

At Build Test Solutions (BTS), measurement is a top priority that we believe is overlooked all too often. In 2018, the UK Green Building Council convened an industry task group to develop a definition for net zero carbon buildings in the UK as part of the Advancing Net Zero Programme. This programme arose from the urgent need to curb the emission of greenhouse gases from the UK’s built environment. This is where BTS’ work largely operates: at the intersection of architects, building managers, surveyors, insulation, retrofitters, and airtightness tests. Our activities are positioned for us to have a better understanding of why the sector is currently responsible for over 25% of the country’s total carbon footprint.

Buildings are often designed at a desk then contracted and constructed without the intention to return to measure how the building performed energy-wise. This is unfortunately encouraged from the approach building regulations and policies take towards encouraging improved fabric performance. More often than not, design intent is the lens through which a building energy performance is forecasted. This is regrettably retrogressive because real-life results tend to vary from initial plans and expectations. The culture of post-construction assessment is the missing link for reducing carbon emissions.

The result is the industry making premature declarations that buildings are energy efficient before we are certain. If a building’s fabric heat loss doubled post-construction, we would be blindsided because measurement is missing. Buildings with the right modelling and construction but poor as-built energy efficiency unfortunately make up most of the UK’s building stock. They underperform not because they were not constructed in line with regulations, but due to the absence of a measurement culture. You cannot achieve net zero if you are not measuring design expectations against real-life results.

Energy Performance Certificates (EPCs) are certainly a step in the right direction. Introduced in 2008, they provide an estimate on a building’s energy performance. Over 20 million EPCs have been awarded since their inception and while we are not saying that they are completely ineffective, experience has shown that there’s more to be desired. Afterall, a survey is intended to be low cost, quick and non-invasive, thus there is only so much we should expect from the assumptions made by the assessor and the arising estimates made by model.

In recent years, the advent of low-cost sensors, smart meters and advances in building physics, knowledge and understanding has culminated in a range of solutions that make building measurements more accessible and affordable than ever before. What this unlocks is the capability of replacing assumptions in our energy models with more reliable measured inputs, specific to the building in question. Measured inputs present an opportunity for building ratings to be as accurate as technologically possible, while remaining cost-effective and able to be produced at scale.

The growing use of measurements are showing that some of the assumptions previously made about the energy efficiency of buildings are inaccurate. For example, older traditional buildings with thick stone walls have often been believed to be far better performing than an EPC shows, and measurement inputs prove this to very often be true. Similarly, many mid-century properties with solid concrete floor slabs, wet plastered walls and ceilings, and uPVC windows are extremely airtight and often far more so than the EPCs predict.

As with all technological developments, the EPC continues to advance. With the acceptance of a greater number of measured inputs, the EPC will develop even further. The technologies providing these inputs are now simple to use, cost-effective and present fantastic opportunities to the building sector at large if we are prepared to embrace measurement technologies; helping to improve the accuracy of insights into building energy efficiency provided to homeowners, landlords, lenders and insurance companies. The outcome is a deliverable that is much more valuable and, due to the conservative nature of assumptions used, buildings will also present with higher EPC ratings; aiding compliance with minimum energy efficiency standards and helping to command better sale and lending rates.

There are a host of local amenities including a newsagent, post office and leisure centre available to residents – all a short walk from the development. An appealing option for families, the area is also in the catchment for Kirkliston Nursery, Kirkliston Primary School and Queensferry High School. Conifox Adventure Park and The Fetching Fox gastro pub are also close by whilst latent defect insurance helps to cover repairs or rebuilding if structural damage appears after the project completion.