Taking action on Climate Change

by Michelle Agha-Hossein, BSRIA Building Performance Lead

Most nations now recognise climate change as an established, perturbing fact that needs immediate attention. We can see the effects in the worsening and more frequent extremes of weather: flash floods, droughts, strong winds, heavy snow, heat waves, etc.

UK temperatures in 2019 were 1.1°C above the 1961-1990 long-term average and it was a particularly wet year across parts of central and northern England. Still fresh in the memory are storms Ciara and Dennis in February 2020 with strong winds and heavy rain that caused significant damage to homes and commercial buildings. There is growing evidence that periods of intensely strong winds and heavy rain are likely to increase in the future.

The UK is not the only country affected by climate change. Many other countries are (and will be) suffering disproportionately. The world’s leading climate scientists have warned that we might have just 12 years to keep global warming at a maximum of 1.5°C. After this point, the risk of extreme weather conditions will significantly increase. The increased frequency and intensity of extreme weather will affect all but is most likely to bring catastrophic consequences in many less economically developed countries, where food shortages and water scarcity can trigger deep social changes.

Immediate radical action is required to limit carbon emissions, and the built environment industry can play a crucial role by changing the prevailing culture.

Most building-related carbon emissions are generated from energy use in buildings. However, there are choices that building owners/operators can make and initiatives that they can undertake to lessen the related negative impact on the environment:

In brand new buildings, the most effective way for addressing emissions is reducing consumption through energy efficient design. In existing buildings, the issue can be addressed by efficient retrofitting and effective maintenance strategy. Adopting renewable energy technologies in both cases can significantly reduce building emissions.

Steps building owners and operators can take today.

There are several initiatives/activities that can help building owners/operators combat climate change:

  • Consider ‘net-zero carbon’ targets for your building: UKGBC launched its Advancing Net Zero programme in 2018 and published the ‘Net Zero Carbon Buildings: A Framework Definition’ in 2019. The framework provides the construction industry with clarity on the outcomes required for a net zero carbon building.
  • Ensure the required outcomes for a ‘net-zero carbon’ building are achieved: As advised by UKGBC in the framework definition, initiatives like BSRIA Soft Landings should be adopted in new build as well as in refurbishment projects to ensure a net zero carbon building will be achieved. The BSRIA Soft Landings framework provides a platform for project teams to understand the required outcomes for their project and ensure all decisions made during the project are based on meeting those outcomes.
  • Maintain your net zero carbon building effectively: Business-focused maintenance is a methodology developed by BSRIA that can be adopted to help building operators maintain critical assets effectively and efficiently to sustain a net zero carbon building within budget.
  • Investigate failure quickly: Is the energy bill for your building higher than it should be? Investigate the problem as soon as you can. The first and easiest step would be looking at the energy end use breakdown to see which areas are using more energy than expected. If the issue is related to the HVAC system, check the system’s setting points and monitor the indoor air temperature and relative humidity. Thermal imaging of the fabric of the building can also help to identify, thermal bridging, missing/damaged insulation and areas of excessive air leakage.
  • Promote a healthy diet among building occupants: This is a non-technical initiative that building owners/operators can adopt in their buildings. Eating less meat and gradually shifting to more plant-based foods is vital for keeping us and our planet healthy.  It is important to think about initiatives such as using signage or lunchtime talks, to educate building occupants about healthy diets and encourage them to eat more fruit and vegetables. Research has shown that adhering to health guidelines on meat consumption could cut global food-related emissions by nearly a third by 2050. Healthy diet is also supported by Fitwel and the WELL building standard.

Building owners and operators, to play their role in combating climate change, should ensure their decisions and the way they create and run their buildings contribute positively to the wellbeing of our planet and its citizens.

So, make a start today and choose the first thing you are going to assess/change in your building to help combat climate change.

To find out more about how BSRIA can help you improve building performance, visit us here.

Shift in Construction Technology for a ‘post-Covid, pre-vaccine’ era

by Amy Butler, JB Associates

In 2017, McKinsey Global Institute slated construction for evolving at a ‘glacial pace’ due to its ranking as the least-digitised industry in Europe. While plenty of technological advances were pitted as ‘on the horizon’, many companies were reluctant to take the necessary steps to push forward with digitisation. Critics warned that a lack of innovation would lead to companies folding, although it took a global pandemic before this prophecy materialised and those without suitable digital infrastructure in place were shaken.

The pandemic is now considered a catalyst for industry improvement, propelling construction out of its ‘glacial’ evolution and deep into the digitised era. A recent study undertaken by Procore found that two thirds of the surveyed construction companies had rolled out new technology during the lockdown, with 94% of these seeing an improvement to productivity and teamwork. However, what exactly are these technologies and where do we go from here?

Smart Buildings

While we are all now experts in the world of Zoom and Microsoft Teams, the challenge lies in returning safely to offices and various other workspaces. With many UK companies pushing for their teams to be back in work physically, how do we ensure that commercial buildings remain safe? Smart Building technology is reshaping the workplace and ensuring safety as well as energy optimisation. Buildings with integrated BMS systems and IoT sensors were already an option before the pandemic. Now, they are a wise choice for business owners.

Essential for a post-Pandemic and pre-Vaccine era, IoT systems can control air quality and ventilation. High-performance air filters and moisture controls will now be key due to Covid-19’s airborne nature. OKTO Technologies (Smart Buildings specialists) have even launched an Artificial Intelligence-led air filtration solution that is reportedly so advanced it can eliminate 99.98% of SARS-CoV-2 (the virus that causes Covid-19) from the air in 10 minutes.

Similarly, density control counters and heat detection cameras can be incorporated into BMS systems to ensure that viruses are less likely to spread or enter into a facility. Airports have been trialling infrared cameras to measure body temperatures for a fever and several companies offer leases or installations for these cameras. While they are not a definitive medical diagnosis, they add a level of reassurance. This may be the aim of much of this technology; a form of due diligence in protecting staff.

BIM & VR

Technological advances are also prominent on site. Construction News reported that contractors employed for the Nightingale Hospital projects found huge value in Autodesk programs. A vital tool for tracking constant streams of updates in rapid working conditions, construction management software proved its worth in recognisably challenging projects across the UK.

As social distancing measures remain in place, it is imperative that technology is prioritised; virtual communication is still far safer than face-to-face. Software like BIM is also providing insights and tools to manage projects during a more challenging time. Even more impressively, companies are merging BIM models with the cloud, GPS and Virtual Reality software. This development means a ‘digital twin’ of a facility can be created and it opens a world of opportunities for Project Management and Design efficiency.

Remote working could even be a trend that stays long past pandemic precautions. Drones have been used previously to reduce safety hazards for technicians and now may be utilised in future remote inspections. Similarly, researchers at the University of Strathclyde have been given £35,000 in funding to create a remote inspection system. The 3D immersive building environment program aims to reduce risks by eradicating the need for Quantity Surveyors or Health and Safety Inspectors to be physically present on site.

Whether enabling remote working, improving the health and safety of commercial buildings or aiding on-site processes, technology has become a necessary tool for construction in the last 6 months. The companies that had embraced digitisation long before 2020 were undoubtedly the ones able to continue thriving in the tough lockdown period. The next step is for many companies is to streamline their management processes or workplace systems to ensure technology works for them as efficiently as possible. Breaking out of its inertia, construction’s ‘glacial evolution’ is firmly in the past and technological advances are here to stay.

This post was authored by Amy Butler of JB Associates – building consultancy specialists. The views expressed are those of the author.

BSRIA Members wishing to make a guest contribution to the BSRIA Blog should please contact marketing@bsria.co.uk

Maintenance of drainage systems to prevent flooding and water pollution

By David Bleicher
BSRIA Publications Manager

Every building has a drainage system. In fact, most have two – a foul drainage system that takes waste from toilets, showers etc. and a storm/surface water drainage system that takes rainwater from roofs and paved areas. Older buildings may have a combined system, and in some locations the infrastructure buried under the street is a combined sewer – a legacy from the pioneering days of city sewerage systems.

As with maintenance of any building services systems, the first step is to know what you’ve got. Every site should have a drainage plan, showing which drains are located where, what direction they flow in and what they connect to. If there isn’t one, it’s not hard to create one – even though the pipes are buried, there’s plenty of evidence above ground in the form of manholes.

When there is a drainage plan, it’s worth checking how correct and up-to-date it is. Sometimes, the exercise of doing this brings up evidence of mis-connections, such as a new loo discharging into a storm manhole. It’s also worth marking drain covers with the service (F for foul or S for storm) and a direction arrow.

Drainage manhole over showing 'S' arrow to indicate storm drainage and direction of flow.

In foul drainage systems, the biggest headaches are caused by things going down the drain which shouldn’t – like wet wipes, sanitary products and hand towels. So the best form of preventative maintenance is to keep building occupants informed, with polite notices and clearly-marked bins in strategic places. Then there is the fats, oils and greases (FOG) that go down the plughole in catering establishments. If these find their way into the drains and sewers, they’re pretty much guaranteed to solidify and cause blockages – sometimes known as ‘fatbergs’. That’s why there should always be an interceptor in place, also known as a grease trap. This needs maintenance – the generic frequency for cleaning out a grease trap, stated in SFG20 (a common approach to planned preventative maintenance), is monthly. But this will be highly dependent on how the facility is used.

If blockages go unchecked, they may also go unnoticed. That is until sewage starts backing up into the building, or overflowing into storm sewers, which eventually discharge into lakes and rivers. These are delicate ecosystems, and the introduction of detergents and faecal matter can be very harmful to aquatic life and of course humans.

Rain, can pick up contaminants from both the air and the land, so once it has reached a storm/surface water drainage system, it has picked up dirt, oil and chemicals from air pollution, roofs and paved areas. Traditional systems have no means of dealing with this, and also must be sized for occasional extreme storm events, so the pipes are very large and mostly used at a fraction of their capacity. Sustainable drainage systems, or SuDS, attenuate the flow of rainwater to watercourses and emulate the way natural ecosystems treat this water. But they need maintenance. For example, any tree routes that could block a soakaway should be trimmed annually, and green roofs may require weeding on a weekly basis during the growing season.

For more information on the maintenance of drainage systems, please explore the BSRIA Information Service

Why use Business Focused Maintenance?

Why do we do maintenance? Is it to keep our assets in optimum working condition? Do we do it to make the equipment last longer? Perhaps the main goal is to prevent failures? If it is for any of these reasons you may find that you are working to an outdated ethos…

BSRIA has recognised and employ a more pragmatic approach for today’s business needs. BFM recognises that the building services’ equipment is installed to provide a service, thereby allowing a business function to be maintained. It analyses the business needs and consequences of failure first and foremost. This ensures that business function is maintained with the minimum of intrusive maintenance to minimise maintenance induced failure, otherwise it is traditionally assumed that the built environment’s asset failure follows the bathtub curve below.

BFM

There are standard specifications for maintenance within the building services industry that have been updated over the years such as SFG20. This is used by many organisations to enable them to tender for outsourced maintenance on a like-for-like basis. The main drawback from this approach is that the maintenance delivered would be generic across the site. This can increase costs and/or reduce the availability of human resources. Couple this with the often-quoted statistic that “70% of failures are due to ineffective maintenance” and it begs the questions to be asked over purely time-based PPM frequencies.

BFM recognises that the need for maintenance generally arises from business needs such as

  1. Complying with legislation
  2. Minimising health and safety risks
  3. Minimising business risks
  4. Managing business continuity
  5. Responding to business and customer requirements
  6. Adding value as part of the business process
  7. Reducing overall business costs
  8. Maximising whole life cost
  9. Increasing asset / system availability
  10. Increasing operational up time

Users of BFM – first published as a BSRIA Guide in 2004 – have demonstrated increased system availability and greatly reduced costs. There is a structured, six-step process to follow where the client and BSRIA work collaboratively to

  1. Assess business needs and consequences of asset failure
    • The goals of the business and the needs of the end users are assessed to ascertain which assets are crucial, and therefore the impact on the business of assets failing. The structure of BFM allows for this task to be done as objectively as possible and logged on a numeric scale of 1-10. 1 is a low consequence and 10 is a high impact on business continuity.
  1. Document functional block diagrams and assess functional resilience
    • review the systems and assess their ability to continue to meet the needs of the business when a failure occurs.
  1. Assess asset condition
    • A full condition survey as per BG 35/2012 taking into account all relevant influences on an assets condition, to provide a remaining life expectancy.
  1. Calculate likelihood of failure
    • converts the alpha-numeric score from tasks 3 and 2 to a 1-10 score via conversion table 6 in the BFM guide BG 53/2016.

BFM1

5. Calculate BFM score

    • combine the score from task 1 (BC) with the number calculated in task 4 (L) to give a BFM risk score on a scale of 1-100.

BFM2

6. Review of PPM tasks and frequency

    • Apply scores to the agreed level of risk set by the organisation. From this a revised maintenance schedule can be drawn up. BG 53/2016 suggests the following;
      • 1-9 Discretionary maintenance for non-critical assets
      • 10-40 Legal compliance and sector specific requirements
      • 41-100 Maintenance to provide the greatest level of confidence in asset reliability, performance and availability.

bfm5

Whilst every job is different, an indicative timeline can show you that BFM can very quickly make it’s impact on businesses.

The business-focused maintenance methodology challenges the planned preventative maintenance frequency of building services plant. The assessment methodology takes into account plant history (age, condition, failure history, plant loading, and maintenance history), the number of standby plant items (redundancy), and the level of resources available.

Many of the intrusive maintenance tasks can be replaced by Condition Monitoring (CM) which in turn leads to Condition Based Maintenance (CBM). The actual practice of CM is far quicker in terms of man hours than time-based PPMs and often involves zero down time to the asset and therefore no impact to the business. In addition to the usual array of gauges on an asset or its BMS sensor display that can be used to monitor plant performance, common CM methods include thermal imaging, vibration monitoring, acoustic emission monitoring and lubricant analysis.

Regular use of these methods at appropriate intervals can be far more cost effective than regular time-based generic intervals, whereas for non-critical plant, the most cost-effective maintenance methodology may be to run-to-failure. By applying the BFM methodology, you can be confident that you have selected the most appropriate maintenance technique for the services in your building.


This article was written by Nick Blake – Principal FM Consultant at BSRIA.

For more information about our research on maintenance and facilities management, please contact: consultancy@bsria.co.uk

To download our publication on Business Focused Maintenance (BG53/2016):
please click here>>

BSRIA's publications on maintenance and facilities management

 

Construction quality could be catching up with other industries

This blog was written by Lynne Ceeney, Technical Director at BSRIA

If you order steak and chips at a restaurant, but the waiter delivers hake in strips, you would be rightly annoyed. Instinctively you blame the waiter, but it could have been a problem with the ordering software, a misreading in the kitchen or just the wrong dish being picked up.  Whatever, you would send it back – it is not what you ordered.   In new buildings, this happens all the time.  Poor communication during the briefing, design and construction process, and poor handover and operation leads to a building that doesn’t deliver the performance the client thought they had ordered in the first place.  Unlike a dinner, it’s not practical to send a building back and wait for the one you asked for to be delivered.  Instead extensive snagging lists, expensive defect resolution and defensive “best we can do” fixes by the facilities team are often used to try and get the building closer to its intended performance – and “closer” is usually the best that can be achieved. The owner and occupier end up with a disappointing building, and the designers and construction company are left with a disappointed client.  The blame chain spreads, and it’s hard to pin down the fault.

The impacts run way beyond disappointment.  Occupier discomfort impacts staff retention, and the increased societal focus on wellbeing indicates that employees will expect higher standards from their place of work.  Poor commissioning or confusing controls mean building systems that don’t work properly and need constant attention or premature replacement, as the uncomfortable working conditions impact on worker productivity.  Inefficient buildings use more energy requiring more cash and causing more carbon emissions.  In fact buildings contribute 37% of UK green house gas emissions from gas heating, and consume 67% of the electricity used in the country.  It’s no wonder that larger investors are taking much more of an interest in the sustainability and performance of buildings rather than just the upfront capital cost.  Good buildings are an asset, poor buildings become an expensive liability in terms of operating costs and void periods. Competitive property markets compound this situation.

With a typical building having a life expectancy of at least 60 years, we are building in problems for this generation and the next.  We’re not great at mass retrofitting, (and the high demand for additional building stock means a capital, skills and material shortage) so we need to get it right first time.  Effective management tools with this aim abound in other sectors, for example DRIFT, (Doing it Right First Time), Six Sigma, LEAN and Zero Defects.  We see the approach being used in food manufacture, car making, pilot training, and patient healthcare, to name but a few sectors.  So what about construction?

Soft Landings is the equivalent tool for the construction sector.  This tried and tested process was developed to help to produce better performing buildings – not necessarily exceptional in performance, but buildings that deliver in operation what they were designed to do in the first place.  Getting a building right requires a shared focus on operational performance of the building right from the start, and throughout the design, construction and commissioning process.  The use of Soft Landings delivers this shared focus, improving communication and collaboration between all parties in the building delivery chain.  It helps everyone to avoid the pitfalls that diminish operational building performance. It fits with RIBA stages, integrates into existing construction processes, and does not require a specific building procurement model.  You can download Soft Landings guidance from the BSRIA website .

However it is always helpful to find out about real world experiences, and to talk to others who are using Soft Landings to help them to produce better buildings.  With this in mind, BSRIA have organised the 2017 Soft Landings Conference (June 16th 2017 at RIBA, Portland Place, London W1B 1AD). You will hear from a range of speakers from different parts of the construction process – including clients – who will explain how they have used Soft Landings in their projects, and the value that it has delivered for their buildings.  You will also hear their hints and tips, and there will be plenty of time to ask questions and take part in discussion both in conference and over lunch.

It’s time for the construction industry to catch up with other industries in terms of quality, to produce buildings that perform as expected, through a delivery process that gets it right first time.  Soft Landings is a process that helps the delivery chain to do this.  For more information on the conference please contact our Events Manager, Tracey Tilbry.

 

Overheating in homes

This post was written by BSRIA's Saryu Vatal

This post was written by Saryu Vatal, Senior Consultant of BSRIA’s Sustainable Construction Group

BSRIA’s Residential Network organised an event on the 22nd of July focussing on the issue of overheating in homes with an excellent line up of speakers. Nicola O’Connor started the day summarising an extensive research project by the Zero Carbon Hub that brought together input from government, industry and academic experts to understand the challenges around tackling the risk of overheating in homes (http://www.zerocarbonhub.org/current-projects/tackling-overheating-buildings). Chris Yates from Johnson and Starley made an appraisal of the assumptions and requirements within the Building Regulations and associated guidance as well as the implications for mechanical ventilation system manufacturers. Neil Witney from DECC explained the challenges around defining and regulating of overheating within homes, current policies and mechanisms that may be introduced in the future in response to the growing body of evidence highlighting the issue. Paul Ciniglio from First Wessex shared the organisation’s findings from several research projects and experience from their own developments, which resonated with issues highlighted by members of the audience. Bill Gething of Sustainability + Architecture and professor at the University of West England brought into perspective how changes in the way homes have been designed and built over the recent years has led to a shift in the performance of homes. James Ford, partner at Hoare Lea discussed some key considerations for designers to address the issue at early stages, to help minimise risk and dependence on active cooling solutions.

Extent of overheating

Evidence indicates that up to 20% of homes in England may already be overheating. Areas where additional risks have been highlighted include:

  • Common areas in apartment blocks, especially where community heating is installed – these areas are not assessed using SAP as they are outside the dwelling envelope. In reality, being unoccupied spaces these are often not modelled for their thermal performance (and energy use) at all. Community heating is being incorporated in an increasing number of projects and the supply network remains live even in the summer to meet the domestic hot water demand. Ensuring that the specification and installation of insulation for the distribution pipework is adequate is becoming increasingly important as buildings are made more airtight. Often stairwells and circulation areas have a high proportion of glazing and, with recent improvements in the general standard of construction and materials, tend to retain a large proportion of the heat gains. It is now important to incorporate a ventilation strategy for these spaces so that the accumulated heat can escape.
  • Urban areas – the average temperatures in city centres can be more than 4°C higher than rural areas. Flats are more common to city centres and these are often close to sources of noise and air pollution and have limited, if any, potential for cross ventilation. All these factors can combine to limit the effectiveness of natural ventilation in addressing the build-up of heat and not just in the summer. Building designs that incorporate large proportions of glazing in their facades, such as penthouses, if not carefully designed, can require air change rates that are unrealistic to achieve, using natural or mechanical ventilation systems.

Need for a definition

A number of sources and definitions are being referred to currently when evaluating for the risk of overheating in homes. These include CIBSE’s Environmental Design Guide A (2006) which sets standards for comfort, although it is not mandatory to use this to demonstrate compliance with the Building Regulations. Dynamic modelling through tools such as TAS and IES offer the opportunity of making a more comprehensive evaluation than SAP, but this option is skill, time and cost intensive. Building Regulations do not relate to limiting overheating for thermal comfort, just limiting the use of fuel and power for air-conditioning. The minimum evaluation for demonstrating compliance with Criterion 3 of Approved Document Part L of the Building Regulations needs to be carried out using SAP. While SAP is not intended to be a design tool, it is accepted that it is the default tool the industry uses widely.

Research projects have highlighted that dwellings can demonstrate a risk of overheating when evaluated against the CIBSE standard but not when modelled in SAP. Surveys from the Zero Carbon Hub study showed that nearly 60% of the housing providers surveyed had checks in place to assess the risk of overheating. However, only 30% of these housing providers explicitly included the requirement for considering the risk of overheating as part of their employees’ requirements to architects and designers. This suggests a missed opportunity for the issue to be addressed early on in the process, when cost and energy efficient measures may be effectively incorporated.

There are several challenges around the definition of conditions under which overheating can be said to occur as several factors contribute to this, including but not limited to air and radiant temperatures, humidity, air velocity, level of activity the adaptability of the individual. There are several checks that can be built into the design process which can help identify the risk at an early stage and allow for a method for mitigating these to be set up and followed through.

Contributing factors
The energy efficiency of homes in the UK has improved significantly in terms of reduction of space heating loads. This has come about in new homes through Approved Document Part L 1A of the Building Regulations and in existing homes through schemes such as the Green Deal. Homes are now less leaky and better insulated to keep warmth in but attention and emphasis is needed on measures to facilitate the expelling excess heat adequately when temperatures rise.

Homes are expected to provide comfortable conditions for occupants all year round and through a range of different occupancy patterns, which may in reality be considerably different to the standard assumptions made in modelling tools like SAP. It is possible that if modelling for thermal comfort is carried out assuming worst case assumptions for occupant density, external conditions and hours of occupancy, many homes would require mechanical cooling. There are, however a number of common sense measures that can be applied to ensure the impact of key contributing factors are minimised. These include controlling solar gains from south and west facing glazing and making provisions for adequate, secure ventilation especially when thermal mass has been incorporated in the structure.
The current extent of overheating in homes must be seen in the context of the anticipated changes in climate. With external temperatures expected to rise with an increased frequency of extreme weather conditions, homes built today must be fit for purpose for warmer summers.

Mechanical cooling?
There has been a rise reported in the installation of mechanical cooling systems in homes in the UK, more noticeably so in the south. While this may be an expected feature in high end homes, the cost of running these systems can be prohibitive, or at least perceived as so, for households where minimising expenditure on energy and fuel is a priority.
There is potential to develop low carbon mechanical cooling systems such as reversible heat pumps. The large scale uptake of these can however have some serious implications for energy supply and the capacity of the grid to accommodate a draw in peak summer months.

Way forward
In addition to affecting comfort, exposure to high temperatures over prolonged periods can have a significant impact on the health and well-being of residents. It is critical therefore to agree on a set of parameters that can help define overheating in homes and this should be carried out with input from bodies such as Public Health England.
Until a definition and modelling strategy is developed, designers and housing providers can refer to several good practice guides and research studies that help embed a common sense approach to design. There is significant potential to mitigate the risk of overheating in homes if early stage design decisions are taken with due consideration for the issue. The limitations of mechanical ventilation systems to help achieve comfort in homes must be acknowledged so that the final burden of an ill-considered design does not rest with the occupants.

References and further reading
http://www.zerocarbonhub.org/sites/default/files/resources/reports/ZCH-OverheatingInHomes-TheBigPicture-01.1.pdf
Design for Climate Change, Bill Gething and Katie Puckett, RIBA Publishing Feb 2013
http://www.arcc-network.org.uk/wordpress/wp-content/D4FC/01_Design-for-Future-Climate-Bill-Gething-report.pdf
http://www.zerocarbonhub.org/sites/default/files/resources/reports/Understanding_Overheating-Where_to_Start_NF44.pdf

To find out more about our Residential Network and to download the presentations from this meeting check out BSRIA’s Network pages.  To find out more about all of BSRIA’s networks contact tracey.tilbry@bsria.co.uk.

Post Occupancy Evaluation: operational performance of a refurbished office building

This blog was written by Dr Michelle Agha-Hossein BEng (Hons), EngD, Sustainable Building Consultant for BSRIA's Sustainable Construction Group

This blog was written by Dr Michelle Agha-Hossein BEng (Hons), EngD,
Sustainable Building Consultant for BSRIA’s Sustainable Construction Group

My Engineering Doctorate study aimed to investigate how and to what extent office building refurbishment can help to improve occupants’ satisfaction, perceived productivity and well-being while optimising building’s operational performance.

A case study approach and a “diagnostic” post-occupancy evaluation style of framework were adopted in this study to evaluate the performance of a recently refurbished 5-storey office building in detail and find opportunities to reduce the gap, if any. The study divided the workplace’s environment into three categories: ‘physical conditions’, ‘interior use of space’ and ‘indoor facilities’. Employee surveys and interviews revealed that interior use of space was the most important aspect of the building influencing occupants’ perceived productivity, well-being and enjoyment at work (happiness) while the improvement of the indoor facilities had no significant effect.

The study also concluded that issues with the physical conditions (such as noise and temperature) causes negative effects on perceived productivity but improving this aspect to a higher level than it is required would not necessarily increase perceived productivity. In contrast, improving the interior use of space aspect of a workplace would increase employees’ perceived productivity proportionally.  These results, however, should be considered with cautious as employee’s satisfaction surveys and interviews revealed that employees’ levels of expectation might have affected their levels of satisfaction with their new work environment.  This could cause some bias in the results of buildings’ performance evaluation. A potential

Old working environment

Old working environment

solution to this issue is to measure occupants’ expectations for their future workplace at the design stage to try to fulfil these expectations as much as possible. How well the new work environment met occupants’ expectations is another factor that should be measured at the post-occupancy stage.

It was also noted that the occupants density at the building was low at the time of the study (17.7m2/person) and that the space was not fully and effectively utilised and more than 50% of the workstations were often not in use. The link between improving space utilisation and the building’s energy consumption as well as its occupants’ perceived

New working environment

New working environment

productivity and well-being merits further investigation. These results are important in the projects where increasing productivity is a key and the budget is limited.

In terms of energy performance and CO2 emission, it was revealed that the actual emission of the building was three times more than the design target. Most of the low cost opportunities identified to reduce the gap were related to the building management and control as well as occupants’ behaviour. I will be doing a webinar very soon on simple energy efficiency tips related to building management and control and occupants’ behaviour. Watch BSRIA’s website for more details about this webinar. 

Emerging themes from Innovate UK’s BPE programme

This blog was written by Peter Tse, Principal Design Consultant for BSRIA's Sustainable Construction Group

This blog was written by Peter Tse, Principal Design Consultant for BSRIA’s Sustainable Construction Group

Back in May 2010, Innovate UK (formally TSB) embarked on four year programme, providing £8m funding to support case study investigations of domestic new build and non-domestic new build and major refurbishment projects.  In total the programme has supported 100 successful projects to provide a significant body of work, that provide insights on the performance of various design strategies, building fabric, target performances, construction methods and occupancy patterns, handover and operational practices.  This work will be shared across the industry providing evidence based information, increasing industry understanding to support closing the loop between theory and practice, ensuring the delivery of zero carbon new buildings is more readily and widely achievable.

Currently project teams are concluding their investigations and collating their findings, and dissemination of the results of the programme will begin in earnest in the first half of 2015.  However, as the programme has progressed, there are some consistent themes that are emerging.  Focussing on the non-domestic projects, I will address a couple of these emerging themes.

The first is around adopting innovative building systems to deliver low energy consumption and comfortable conditions, and unintended consequences associated with these technologies.  This covers a broad spectrum of building technologies including solar thermal, heat pumps, biomass boilers, earth tubes, rainwater harvesting, controls and natural ventilation strategies.  Innovation in its essence will have some inherent teething problems, which is often overlooked in the charge towards reaching our carbon reduction targets.  The obvious default stance is to specify proven and reliable technologies which are delivered by a team that is familiar with the technology, but our journey towards delivering true low carbon building in operation would inevitably be prolonged.

An additional level of complexity can be added with innovative systems; one healthcare facility introduced solar thermal and a combined heat and power (chp) unit, to supplement natural gas fired boilers for heating and hot water requirements. With several sources of heat complexity is added to the control strategy, trying to strike a balance between changing heat demands of the building and optimisation of the system.  This complexity, coupled with a requirement for increased operator understanding often leads to system underperformance.

The practicalities, maintenance and associated costs of innovative systems is seldom fully realised by clients.  An office reported success of the rainwater harvesting system, but were surprised at the frequency of filter changes to mitigate the system being blocked.  Another office had to regulate a fan associated with earth tube ventilation system, as running at a higher speed caused too much noise for occupants.  A school had ingress of water to an underground wood chip store rendering the biomass boiler idle for significant periods.  A hotel employed automatic external blinds which retracted in windy conditions to avoid damage, thus offering no shade to occupants during sunny, windy days.

DC-Innovative-Construction-Services-Building-Maintenance1It is clear a reality checking process is required for design decisions to mitigate such matters.  BSRIA’s Pitstopping guide, which resides within the Soft Landings framework describes a process that allows construction teams to periodically reconsider critical design issues by focusing on the perspective of the end user.  This also provides an opportunity for the client to understand the full ramifications of implementing innovative building systems for a more informed decision, and to align client expectations.

The second theme involves the process in delivering innovative technologies, with a particular a focus on commissioning and handover.  The commissioning period residing at the end of the build process is often susceptible to being squeezed.  When the decision has been taken to adopt an innovative building system, there is increased pressure during commissioning to ensure the system is operating as intended.  With the additional complexity associated with innovative technologies, it is vital the commissioning time is adequate to complete comprehensive scenario based testing; how is hot water delivered if the solar thermal does not provide a contribution, how is the building operator alerted the status of the system, how can the operator diagnose the problem, how long can the system operate without the solar thermal contribution without major detrimental effects etc.  To ease the burden on the commissioning period, it is clear commissioning should not be afterthought, but an integral part of the build process.

The commissioning period also signals a time where many of the stakeholders with tacit knowledge of the innovative building systems have changing responsibilities. It is vital this knowledge is captured for users before the opportunity is lost.  Building manuals, user guides and logbooks need to be completed so users can relate to their building environment, understand control of the environment and capture major alterations.

Figure 1 - South façade showing café, street and incubator office blockMany projects reported that guidance for both users and operators was often lacking, with several BPE teams developing guidance as part of their projects to support users.  Commonly BPE teams have also struggled to find initial design intent and operational strategy associated with innovative technologies, highlighting the importance of handover documentation.  Training of users is another key element to knowledge continuity, but several projects reported changes in staff being a core reason for innovative systems underperforming, as documentation was not kept up to date.  The value of clear concise user guidance is evident; BSRIA’s Building Manual and Building User Guides helps individuals responsible for creating building logbook and user guides.

In this blog, I’ve only addressed a couple of areas in regards to emerging themes, to hear more about findings from the programme, come hear me speak at the Energy Management Exhibition (EMEX), at Excel, London on the 20th November, 2014.  Additionally, join the BPE community at connect.innovateuk.org, and search for Building Performance Evaluation.

Designing for change

Ian Harman of Marflow Hydronics (BSRIA Members)

Ian Harman of Marflow Hydronics (BSRIA Members)

With the industry moving at such a fast pace, new innovations are being introduced all of the time. Manufacturers are inventing great new products that offer many benefits; solving the problems of the present to provide a better future. The biggest problem that they face, though, is launching these products on to the market. This is where BIM could really help. 

I think it’s fair to say that people don’t really like change. We like to stick to what we know and what we feel comfortable with. This seems to be the case in our industry. Many people, from consultants to installers, are still completing jobs and planning projects in the same way they’ve been doing it for years; that is in very traditional ways. A prime example is how there is still much use of two port control systems despite Pressure Independent Control Valves having been around now for quite a while. These newer products are faster to implement and more reliable in the long term, yet there is still a reluctance with some people to adopt the new technology.

It’s true that with any new product there’s inevitably a big learning curve to using them, and often training can be time consuming. There’s also the fear of risk. If people use a new product that they’re not so familiar with then there’s always the chance that it will go wrong. This could be because the user isn’t so experienced at using it, but also it could turn out that it wasn’t the ideal product after all and sometimes knowledge and experience can really help when making decisions. This is where BIM steps in.

Using BIM, manufacturers can create models, which I like to think of as ‘Lego blocks’, that they can send to customers to introduce them to a product. And they can do this long before any decisions have been made, at the very initial stages. The ‘Lego block’ would be a visually simplified model that not only clearly defines the spatial envelope and connection points, but also includes a wealth of ‘metadata’. This ‘metadata’ contains data fields specific to the particular products, such as flow rates for valves or electrical loads for powered devices.

BIM - Marflow Hydronics
That all means that clients can look at the products in detail and trial them in their plans from the very beginning. They will be given the time to properly analysis products and see how they will work within the system and how they will interact with other components.

By starting with the end in mind and properly understanding the system at the initial stage, it will help to future proof the project far down the line. It’s also the cheapest time to detect any issues. The easiest time to make a design or selection change is at the beginning of a project and BIM facilitates this in a much more user friendly manner than ever before. This would undoubtedly give them much more confidence in the products they’re looking to use and would, very importantly, remove that fear of risk.

BIM provides users with the time and ability to put much more thought into their projects earlier on, minimising that risk further down the line. This then increases the chance of far more successful project that works with the best products, potentially the latest and more developed ones, and there’s much more chance of it being on time and to budget.

BIM 2 - Marflow HydronicsManufacturers, like Marflow Hydronics, have been doing this to help bring new products into the limelight that otherwise customers may have been apprehensive about. More importantly, this has helped all parties get the right products specified when they may not have been otherwise. BIM may be the ideal solution to help us move more quickly into the future using more innovative products and having many of the niggling issues that have been around for so long vastly reduced, if not eliminated.

This was a guest post by Ian Harman, Technical Applications Engineer at Marflow Hydronics, BSRIA Member

If you are looking to find out more information about BIM, BSRIA runs two specific training courses:

There are also several other blog posts focused on BIM as well as a BSRIA BIM Network. 

The selection criteria of refrigerants

Salim Deramchi, Senior Building Services Engineer at BSRIA

Salim Deramchi, Senior Building Services Engineer at BSRIA

This is part two of a three part series from Salim. You can read part 1 here

There is no general rule governing the selection of refrigerants, however there are of course the five classic criteria and those are:

  • thermophysical properties
  • technological
  • economic aspects
  • safety
  • environmental factors

However, in addition to these criteria, others have to be considered such as local regulations and standards as well as maintainability and ‘cultural’ criteria associated with skills to support the units, application, and user training requirements.

The best approach when presenting evolution and trends is certainly the per-application approach. The desirable characteristics of “ideal” refrigerants are considered to be:

  1. Normal boiling point below 0°C
  2. Non-flammable
  3. Non-toxic
  4. Easily detectable in case of leakage
  5. Stable under operating conditions
  6. Easy to recycle after use
  7. Relatively large area for heat evaporation
  8. Relatively inexpensive to produce
  9. Low environmental impacts in case of accidental venting
  10. Low gas flow rate per unit of cooling at compressor

The choice of alternative refrigerants should involve a review of recycling or disposal of refrigerants. You must decide which criteria for the ideal refrigerant is of most importance to your organisation. It must be considered that the operation phase is the key factor when determining the environmental impact of the various refrigerants as there is less impact to the environment in the production and disposal stages. As an example, supermarket retailers are steadily moving away from long-established HFC refrigeration systems.

Decision making for new refrigeration plant using refrigerant alternatives such as ammonia, CO2 or hydrocarbons, which have comparatively little or no impact on global warming and zero impact on ozone layer, should consider not only the impact on the environment but the additional required skills to maintain (Ko Matsunaga).

You can  find out more information in BSRIA’s library

%d bloggers like this: