How the industry can help buildings last longer with more efficient performance
Stuart Smith, Group Sales Director and indoor air quality specialist at ventilation manufacturer Nuaire, discusses the modern-day concerns on indoor air quality and overheating.
New buildings across the UK are being built and designed for greater efficiency, sustainability, and decarbonisation in line with the industry-wide net-zero approach – and that is a great success story for the 20% of buildings and homes still planned for 2050. However, when looking at efficiency and how we make our existing stock greener, the focus and energy seems to decline as puzzled faces debate the best approach.
Older working buildings pose their own complex efficiency issues, from overheating to ventilation effectiveness and heat retention. Often built against old building regulations, the refurbishment and refit of these buildings must become a focus for 2050 as much as new stock – as an industry, the focus needs to be on making them better if we hope to drive better returns for both people’s pockets and the planet.
The main question we face is how we do it. In terms of ventilation and air movement, we see buildings suffer under years of change, with problems being tackled piecemeal – from desk moves in an office to tackling solar gain for buildings with south-facing facades - but never completely overhauled to make a difference in the building in its entirety.
Overheating is one of these major issues and one that is causing the industry great concern. In our efforts to create more energy-efficient buildings and make our existing buildings less leaky – the more we are making buildings ‘airtight’, through triple glazing and insulation. This, in turn, creates ‘heat boxes’, which raise another set of problems to solve.
There are many contributing factors to overheating: climate change spiking summer-time temperatures, architectural glass design demands, buildings being built ‘too tight’ and the requirement for high-rise builds due to inner-city conurbations with limited space.
Not only does overheating have a major impact on whether the property is occupiable, in some cases making it uninhabitable in the summer months, but it can also cause serious problems with lethargy, heat stress, and other major health risks. At its worst, it can result in premature death. Addressing the issue from the inhabitant’s point of view is something the industry must start to do – it isn’t enough to use air conditioning to cool the room while circulating stale, dirty indoor air. These buildings need cooled, filtered air to ensure occupant wellbeing.
The MET Office has documented that the number of ‘extremely hot days’ could increase fourfold from 10 to 37 percent if global temperatures rise by just 7.2°F – adding alarming concern to the issues overheating causes. CIBSE has also advised that if the issue is not addressed, 4500 premature deaths per year are expected by 2050 *1.
In addition to this, experts claim that the global temperature is likely to rise 1.5 degrees above pre-industrial levels by 2051 and heatwaves will increase in frequency making this an issue that won’t go away and should not be ignored.
It is known that 4.6m homes in England are already reported to have overheating problems, with more new builds being built set to face these same issues.
Current building systems struggle to find the optimum temperature to keep all satisfied. It’s the Goldilocks Principle – finding just the right amount – of heating, cooling, and ventilation. However, there are solutions out there that can be specified for both new and retrofit builds. These solutions, coupled with on-demand ventilation solutions will offer good control over the indoor air quality within a building as well as make them very energy efficient.
For future builds, it’s about making this a part of the mandatory checklist at the initial design stage. It will come down to architects and specifiers to advise accordingly to tackle this issue and future-proof building systems to keep properties healthy and habitable going forward.
Hybrid wins in popularity
It is time for a fresh look at how we ventilate and create an optimal thermal temperature all year round within a building. For residential apartments, with often no option for natural ventilation, mechanical clean air input and extract is a necessity, and therefore a new hybrid heating and cooling system needs to be considered to help with the optimisation of temperatures.
Nuaire’s new Hybrid Cooling Module, an ancillary that works with our MRXBOX MVHR to provide a hybrid MVHR/cooling system, is one such solution - delivering clean indoor air and heat recovery while combating overheating in the summer with additional cooling.
A cooling module is a self-contained unit, ideal space-saving for retrofit installation above an existing MRXBOX ECO 5. It is an ideal solution for consultants looking for peace of mind in a product that will not only mitigate overheating but retain heat in the colder months, whilst keeping the indoor air quality high all year round.
Intelligent controls for greater efficiencies
For added efficiencies, solutions work best with a fully on-demand ventilation system control base.
Currently, only one in five commercial buildings operate with a basic Building Management System (BMS), despite Europe being the third-largest energy consumer in the world.
Moreover, today only 80% of commercial buildings are operating at class C energy efficiency with timer-based programming rather than sensor-based, demand-orientated activation when it comes to ventilation and cooling. These buildings are literally throwing money away with energy wastage.
The advanced functionality and expanded solutions when it comes to smart controls, can provide impactful energy efficiency and cost savings with networked connectivity and site-specific controls that monitor trends to adapt to meet site requirements.
With the adoption of smart controls for these operations, buildings would see better indoor air quality and greater efficiencies in each season, from summer through to winter, with systems adapting to the need of the occupied space.
A new outlook for the future
A greater focus needs to be placed on indoor air quality – currently a no man’s land within building regulations with a complete lack of emphasis on ventilation effectiveness. These important considerations within any building, be it for schools, offices, or at home, will be essential for the ongoing protection of the occupants who will be making use of that space.
I’d like to see the industry take a different tact with ventilation, heat recovery, and cooling going forward, focusing on the individuals that use the building rather than solely the fabric of the building itself.
What may have been an effective method of ventilation when a building was first built may no longer be suitable, whether it be a commercial or a residential building. Most ventilation systems do not have the flexibility to adapt as these buildings’ internal structures and usage change over time.
The temptation to go with the most basic solution is an outdated and inefficient approach. A well-being standard must be maintained and education is key. Understanding how the air moves, heats and is then cooled efficiently is vital.
As an industry, we need to future-proof our buildings by looking at the way the space is used and how it may need to adapt over time, and only then can efficiencies be maintained.
1 Cibse.org. (2021). CIBSE - Overheating Position Statement. www.cibse.org/news-and-policy/policy/overheating-position-statement
Stuiart Smith is Group Sales Director at Nuaire