The importance of investigating failures in building services

Pinhole corrosion of radiator (outside surface)
Pinhole corrosion of radiator (outside surface)

A study from the UCL(1) revealed that building failures may cost the UK construction industry £1bn to £2bn every year. This was a conservative estimate made in 2016, based on 1 to 2% of the total value of construction.

As of March 2020, the Office for National Statistics has estimated the total value of all UK construction works to be worth £12.7bn, 68% of which is for new buildings or the repair and maintenance of existing buildings. This would give an estimated cost of failure between £85m and £170m, of which building services would account for a high proportion.

(1) Razak, D S A, Mills, G and Roberts, A (2016) External Failure Cost in Construction Supply Chains. In: P W Chan and C J Neilson (Eds.)

Types of failures in building services

Bathtub curve regarding types of failures in buildings
Bathtub curve

The typical pattern of failure arising against time is shown by the well-known bathtub curve. The curve is divided into three segments: an infant mortality period, usually marked by a rapidly decreasing failure rate; a random failure period, where the failure rate continues at a

The first period is usually detected during the defects liability period after a project is handed over.

The second period would happen during the operation of a system, and failures may occur due to inappropriate operating conditions or maintenance regimes.

The third period is when the system is reaching the end of its life. Failure could be imminent and there should be little or no surprise in this happening.

Importance of investigating these failures

Showing house made of money i.e. there is cost in everything, so always investigate to prevent repetitive failures
There is cost in everything: Always investigate to prevent repetitive failures

There are various reasons why every unexpected failure should be investigated. Below are some of the key ones:

  • Insurance purposes. Insurers may require an independent evaluation of the failure and investigation of its possible cause to identify possible fraudulent or malicious intentions.
  • Cost savings. Too often, failed components are replaced without investigating the root cause. Without understanding the origin of a failure, it is not possible to prevent its re-occurrence. Repetitive failure and replacement of components could add significantly to the operating cost for a building or estate.
  • Health and safety. In May 2009, a lift at London’s Tower Bridge tourist attraction suffered a vital mechanism failure that sent it falling with 9 people in it, four of whom suffered bone fractures. The malfunction was caused by the failure of a counterweight mechanism. The accident investigation by the HSE revealed that there had been several previous component failures with the counterweight mechanism, and the components had been replaced without proper review, and with no investigation into why they were failing so early. Tower Bridge was ordered to pay a total cost of £100k, and the HSE concluded that, had there been a proper review into the counterweight mechanisms, the catastrophic failure of the lift could have been avoided.

BSRIA can help with building services investigations

BSRIA has been in the building services industry for over 60 years and has been involved in hundreds of investigations.

Our independence makes us the ideal partner to provide non-biased failure investigations. Our expertise and capability in testing various materials and components of building services to determine the likely cause of failure is unique. We are able to perform investigations on site, examinations in our labs and analysis in our offices.

Our professional approach is such that there is no failure too large or too small to investigate today because this can save lives and costs tomorrow.

Read more about BSRIA’s Failure Investigation service here

Author: Martin Ronceray, BSRIA Engineering Investigation Lead

The BSRIA investigation team can be contacted at

+44 (0) 1344 465578

Investigations@bsria.co.uk

Review of the BSRIA Briefing 2013 – Changing Markets, New Opportunities

“Construction is the last of the big industries to go digital”, John Tebbit, Construction Products Association

November 2013 saw another brilliant BSRIA Briefing held as always at the fantastic Brewery in London. The event was chaired by John Tebbit, Industry Affairs Director at the Construction Products Association with c400 industry professionals in attendance. The speakers this year were focusing on customer satisfaction, data centre trends, changes in building practice and design decisions, smart technology leading the industry forward and the internet of things.

Chairman John highlighted two key issues facing the industry, the Construction 2025 strategy and the move towards Low Carbon as well as the construction industry being the last industry to go digital despite a demand to do so.

Bukky Bird talked about Tesco as a continuously changing organisation by highlighting some of the company’s historical milestones. From Tesco’s founder Jack Cohen opening a market stall in 1919 to becoming a global company with just over half a million colleagues today.

Bukky also highlighted some current customer expectations and key drivers for this such as the current economic context. She emphasised the need for organisations to understand and respond to changing needs and environments.

“A green agenda is a prerequisite of what customers expect from a brand like Tesco”, Bukky Bird, Tesco

“A green agenda is a prerequisite of what customers expect from a brand like Tesco”, Bukky Bird, TescoToday’s customer is under pressure, struggling with rising costs and dealing with lifestyle changes. The focus is therefore on family and the home, with a real expectation that brands should reduce waste and save money. Responding quickly to these needs is critical for retailers like Tesco and this should therefore drive the focus through the industry supply chain.

A challenge facing our industry is how to develop true partnerships to tackle these problems. Bukky highlighted the need for flexibility, agility and the need for the industry to be willing to change. The customer is changing radically and the building industry needs to be ahead of this curve.

Historically we have been very slow to adapt, and this is an opportunity to buck that trend. Her final point was that the industry are not supplying Tesco, but Tesco’s customers – understanding the customer’s needs and developing innovative solutions to meet these is key to successful partnerships.

“Nobody ever did anything to be green, they did it to save money”, Nicola Hayes, DatacenterDynamics

 Nicola Hayes looked at a rather different sector focusing on data centre trends and energy. Datacentres Nicola argued are the buildings you do not see, the hidden side of the industry and yet becoming a central part of several industries as people relocate their data to the Cloud. Nicola discussed the fact that Datacentres may be hidden but they do suffer negative publicity mostly due to the energy usage of such buildings and the accusation from the Press that they are singlehandedly destroying the planet. When viewing the industry as a country, the industry uses a little less energy than the UK as a whole, marked at 332.9TWh which is an exceptional amount and understandably a worry for the industry and a target from the Press.

But it was the trends that Nicola was concentrating on, where the Datacentre industry has come from and the expectations of it for the future. In three years the industry has grown from $86bn to a staggering $120bn as well a doubling in space used for the buildings, growing from 15million sqm to 31million sqm. The growth of Datacentres is down to several other key industries, the rate of increase has risen for Professional Services, Energy & Utilities, Industrial & Process and Media & Telecoms. With this growth there has been a change in how Datacentres are being built and their operations. There has been a 15% increase in outsourcing for the industry since 2007 rising to nearly a quarter of the industry but IT Optimisation still remains a major investment.

For the built environment the biggest change Datacentres has had for them is the increase in energy monitoring and the storage of millions of data bits. People in the world, particularly the US, UK and Germany are starting to become more conscious of energy efficiency therefore more business is generated for the Datacentre industry through big data from energy monitoring. Nicola pointed out that this is not done for a purely ‘green’ reason but primarily to monitor costs which are why most universities do not monitoring as they are not responsible for the financial side of their energy use.

With there being such a focus on energy efficiency, the way Datacentres are being built has also been a changing trend with there being 25% increase in the number of retrofits of Datacentres while there was only a 2.1% increase in the number of new builds. Efficiency measures (to answer to the Press criticism) are also now determined from the outset. However despite Datacentre industry growing at a fast rate there are risks involved for the industry from the small scale of compliance to the large scale of terrorist attacks. With these risks comes an important debate that is happening within the industry, cost vs. risk.

“There is a market for MVHR but we need to get better at delivering it”, Nigel Ingram, Jospeh Rowntree Housing Trust

 Nigel Ingram continued with a discussion about social housing and the consideration of end users when designing buildings. The Joseph Rowntree Housing Trust currently looks after 2,500 homes in Yorkshire and Hartlepool. Nigel discussed one particular project the Housing Trust are involved in, the Derwenthorpe village which looks at the lessons learnt from past projects and how they can improve their buildings. The way the Joseph Rowntree Housing Trust decided on best building practices was through experimentation over four years, they built two prototypes and used 17 different methods and as many M&E components as possible including grey water harvesting and block work systems. The aim of this experimentation was to see what worked to create the best possible building.

As well as all these design considerations Nigel also enforced the importance of the end user and their lifestyles with the Joseph Rowntree Housing Trust looking at how people live in buildings and what changes in lifestyles are expected in the future and how best can the prepare buildings for that. There were three main points that made up the JRH’s strategic servicing infrastructure, the first being fibre optics. The Trust believes that with the use of technology ever increasing including internet, television packages etc. they needed to invest in a viable cabling network. However none of the big companies were prepared to discuss such a project therefore the Trust developed a joint venture with an investor to set up their own fibre optics for the estate, by doing so they satisfied the customers and set them up for any increase in connectivity in the future.

The second point the Trust considered was Communal Heating, they looked at a variety of different heating techniques for the estate such as low ground source heat pumps.  Communal Heating was decided on in 2007 from a carbon footprint point of view as at the time the Code of Sustainable Homes was announced with zero carbon targets by 2016. Communal Heating is notoriously difficult to get working efficiently, just like any heating system however after it was distilled down into the six components that worked for the Trust it was able to provide fuel security and prince control for the future residents which is what users wanted from their buildings. The system now works and is one of the only systems in the country that is successful and has been contracted for 25 yrs to a European Communal Heating group.

However Nigel wanted to point out that the Derwenthorpe village has not been completely successful, the final point in their strategic servicing infrastructure was MVHR Systems. The project has not seen any success with these systems, it has been installed in 64 houses but customer feedback has been negative and there are many issues with it. As an alternative MEV is now being used. Nigel stresses that there is a market for MVHR systems but for it to work there needs to be massive improvements in the industry in terms of commissioning, installation and maintenance. There seems to be a technology focus rather than process and this needs to change if the industry is to satisfy clients and users of buildings.

Nigel’s main focus for the Derwenthorpe project was customer satisfaction, the importance of the end user. Fibre Optics and Communal Heating was installed for the benefit of the residents of that estate as they have certain expectations of the way they live including operational and financial. The Joseph Rowntree Housing Trust has focused on the end user for their design plans rather than what should work from the industry perspective. Rigorous testing and accepting systems aren’t right has gone into making sure buildings are built as best as they can be which is important for our industry, it’s taking into consideration the mistakes made on previous building stock and learning from them and also considering the occupants and their needs.

“The Cloud is as suited to small buildings as it is to big buildings or building portfolios”, Jeremy Towler, BSRIA

 Jeremy Towler reflected on the “smart” built environment and how we get there. Jeremy highlighted that there is a lot happening and changing in our industry emphasising that we are the last industry to go digital despite there being several opportunities for digital work particularly wirelessly. BEMS will become an increasing component of buildings, modules will be built off site and therefore digital technology needs to be an important investment. Mobility will also become a more important part of the built environment, currently everyone uses a mobile but with geo-location buildings will be able to recognise everyone in buildings and respond dynamically. With this the collective voice of the occupants starts to influence the building which could be quite revolutionary.

Building Analytics are also an important step towards a “smart” built environment, increasingly buildings have sophisticated software that permits building operation and how best to optimise them. With Building Analytics becoming a more common part of our industry there has been a move towards the Cloud which has allowed data mining to reveal relationships and trends we never could have imagined. With these advances also comes the development of Smart Cities, particularly in China where there is a commitment to build at least 30. Jeremy defines smart cities as an incorporation of intelligent buildings, broadband connectivity, innovation, digital inclusion and a knowledge workforce.

But Jeremy states it’s not just smart cities we have to consider, its smart grids and smart buildings. Smart grids is an advanced power grid for the 21st century, essentially it is a decentralised multi directional model where energy and information can flow from supplier to consumer and vice versa which enables a variety of new applications for homes and businesses. Smart homes on the other hand have reached a critical mass and are due to break into the standard housing market but with this there has been an opportunity seized by the utilities who are now offering connectivity.

With smart homes becomes the internet of things and the ‘ubiquitous homes’ where sophisticated systems learn behaviour and respond accordingly, like our mobile phones that can tell us where we want to go and how we need to get there, such software will be used in our own buildings to provide our homes with the settings that we need. However the current built environment is a long way from becoming a smart industry, currently more than 75% of the building stock has no intelligent controls which is primarily to do with the age of the buildings with over 40% of total stock being built before 1960. With this in mind there is an opportunity for the industry to consider a great deal of retrofit projects but for smart technology to work to its best potential for the built environment the industry needs new skills developed through training in software and hardware analysis.

“We are now accountable for how our buildings perform “, Michael Beaven, Arup Associates

 Michael Beaven continued on this theme of the industry needing to change but instead focused on workflows. Arup has learnt that change is beneficial to the industry, adaption is necessary to meet the needs of the client. Arup have changed what they do and how they do it, learning that doing things the same way over and over again is to no benefit. However despite the need to adapt there are constants within the industry, carbon being the main issue for energy costs and emissions for companies in reputational aspects as well as the bottom line an example being Sky who are very forward looking including reducing the carbon of their set top boxes from 10 to 4 watts saving 20megawatts to the grid.

Importance of energy and efficiency is paramount but so is what we build it with. Embodied carbon is a key player in how we build our buildings now; decisions are being made on where products come from and their whole life cycle rather than primarily cost efficiency. Buildings are also being tested now, everything is monitored in our buildings so we can learn how to improve them, we are accountable for how buildings perform. From this we can learn how to design buildings that are successful for end users.

Michael also emphasised Jeremy’s point of the internet of things, how the integration of IP controls are making building betters and even the advancement of BMW considering smart transport for smart cities. Building on the interaction between traffic signals and mobile data to develop relationships between them to better control traffic, even where you park will be managed in a smart way. Another important development in terms of smart technology is that people are now connecting and sharing information on what works for a building and how best practices can be established.

One of Michael’s most important arguments was the importance of BIM and the matter that we as an industry really need to get up to speed with it. It’s client driven so we need to be on board as it is not only changing our workflows but also our business, without a grasp we lose projects. There also needs to be an acceptance that BIM is not just about 3D drawings and design but rather it should be a changing of our work streams to digital.

BSRIA Briefing panel answers questions from the audience

Michael’s final point tied in one of the key themes of the morning, customer satisfaction or rather the importance of the end user. Arup are moving towards an end user focus, designing buildings for people rather than the client or the architect. He used Sky as an example of a company championing a place for people, designing a building that understands what the user wants rather than what is considered the best design. Michael emphasised the feedback loop, empowering people to vocalise what they want in a building, what controls work for them, with that Soft Landings is critical for discovering what works and what doesn’t and resolving these issues before a project is completed.

There were a variety of thoughtful questions throughout the morning ranging from what the industry is doing to combat the UK’s power supply reducing to 2% by 2016, John Tebbit argued that the UK needs to stop investing in the UK and instead build industry abroad and import into the UK. There was also discussion on why there are so many installations problems within the industry, Nigel Ingram suggested there was too much blame placed on the end user, that there needs to be more ownership of mistakes and to learn from them if the industry is to move forward. This was the key theme throughout the morning, for the industry to move forward in any pursuit especially digitally we need to focus on trends and accept change as a good thing. But when accepting change we also need to learn from our past mistakes rather than continue to avoid them.

“Change comes from doing 100 things 1% better”, Sir Clive Woodward

Following lunch guests were treated to an afternoon speech from Sir Clive Woodward who continued the theme of change being necessary to move forward and how that worked for the England rugby team and the British Olympic team. Sir Clive’s talk looked at the 3F’s or 6F’s argument and interestingly the importance of an Australian dentist and his impact on working habits. He emphasised the effort of a whole team being behind any win and argued that talent is not enough but learning, calmness and hard work are needed to leverage it.

A special mention also goes to Chris Monson, of main sponsor Trend, who was awarded an Honorary Membership of BSRIA, becoming only the 8th person honoured. Chris accepted the award from BSRIA Chairman Leslie Smith and thanked the company as well as the industry.

A big thank you to all delegates that attended and the speakers who gave their time to the event. Also thanks to Sir Clive Woodward for being our afternoon speaker and rounding up a fantastic Briefing.

To download the presentations from the event go to BSRIA’s website.

ECO scheme – carbon reduction or wealth redistribution?

Andrew Eastwell, BSRIA CEO

Andrew Eastwell, BSRIA CEO

The issue of retail energy prices is now THE political hot potato.  The invisible green taxes attached to household energy bills have suddenly become glaringly revealed and politicians of all hues are now looking at these supplements as serious vote losers.  But are they such a bright idea anyway?

The question really is about the use of hypothecated funds harvested from energy bills and used to create a kind of wealth redistribution in favour of energy-poor households.  Under this scenario there is a transfer of wealth from richer households to improve the lot of lower earning households by improving the energy signatures of their homes. The ECO scheme is not so much a carbon reduction scheme as a wealth redistribution tool.   The scheme does however have the twin benefits of deriving a relatively secure revenue stream and, by increasing the costs to “donor” households, acts as an  additional incentive for them to be efficient with energy too.

The problem, as always, lies in the continued confusion between issues associated with energy (and cost) and the release of carbon.  If carbon is the real enemy (as I believe it is) then this scheme is at best sub-optimal.  This is because although renovation of homes will undoubtedly improve the comfort of energy-poor households there is little compelling evidence to me that the costs involved (including the not insubstantial cost of administering the schemes) provide the biggest carbon reduction bang for the buck.  This is partly because improvements in dwelling performance are likely to be taken as comfort gains rather than energy saving.

We have just seen that it has been necessary to use Chinese money and what is widely regarded as a substantial central support mechanism in the fixing of a strike price for generated new nuclear electricity in order to stimulate the building of new nuclear (non carbon generating) capacity.  It is the very high up-front costs of building these facilities that is the problem.  Would it not be better to use the ECO funds as cash support as  low carbon generation building programme – nuclear, wind, tidal or whatever gives the best CO2 return per pound?

by thinkpanama

by thinkpanama

This then begs the question as to who should fund the improvement of poor dwellings.  Actually this is not so much a carbon issue as a social equalisation programme.  In all normal circumstances this has historically been met from general taxation in the form of grants and I can see no reason why this should not be the case in the future.   Perhaps, rather than distributing a £200 annual winter fuel allowance this might better be used in improving dwelling energy (not necessarily carbon) performance.  The private market for Green Deal products simply does not seem to have become excited at adding debt to the household for what are perceived as intangible gains.  Households understand cash and a more direct approach to funding Green Deal improvements through this means or indeed other mechanisms such as stamp duty may be a more efficient means of getting to the problem homes.

In summary:  Use hypothecated funds, such as ECO for the purpose they were intended  – getting carbon out of the system.  Use the money to support the most cost efficient means of doing this irrespective of mechanism for delivering this objective.

Don’t confuse wealth re-distribution with carbon saving – it distorts process and gets caught up with political weather cocking.

If Buildings Could Talk to us…

It was really only a matter of time:

This blog was written by BSRIA's Henry Lawson

This blog was written by BSRIA’s Henry Lawson

Buildings are where we typically spend the greater part of our time, both at work, and often as not outside of it.  They already consume about 40% of the energy used in most advanced countries. They represent a huge proportion of our investment, both as individuals and as a society.  For centuries the technology of the day has been deployed to make them more efficient, comfortable and healthier for their occupants.

The surprise is surely that it has taken so long for information technology to really  move centre stage in our buildings. While smart homes remain, at least in most countries, a slightly geekish luxury item, many of us already spend our working day in environments managed by quite advanced  building automation systems, which aim to maintain a safe, secure and comfortable environment.

As building systems become more sophisticated, the more critical it becomes to be able to collect information about the state of the various components, and how they are interacting.  Accordingly, leading building automation and controls (BACS) suppliers, including Honeywell, Johnson Controls, Schneider Electric and Siemens have increasingly been making software available in order to process and make sense of this information.

In this they have been joined both by some of the big enterprise software players, but also by a host of  comparative newcomers. A key factor here is that the amount of data and the complexity involved can be quite large. It is easy to see that if you are in the position of managing a large portfolio of buildings, perhaps as a facilities management company, then if these buildings are automated then you may have to analyse a large volume of data to ensure that your estate is performing efficiently in terms of energy usage, costs, maintenance schedules, etc.

What is less obvious is that even for a comparatively modest sized building, the data can be potentially quite complex.  To get top performance from a building you need to look beyond the obvious. This means not just taking account of data from individual sensors or other information generators, but how these each  interact with one another. For example, one surprisingly common scenario is where the temperature in a given zone is fine, but only as the result of a heating system and a cooling system battling each other to standstill, wasting alarming amounts of energy – and money – in the process.

To identify these types of scenarios the system needs to be able to check very many different measurements against other ones and

The BACS Market

The BACS Market

identify relationships and correlations. And once the “normal” patterns and correlations have been identified it can then look for anomalies, which may be a warning sign that something has gone wrong, or at the very least that something abnormal has happened. Why for example, might a temperature be spiking in one part of a building at an unexpected time?

It is these kinds of challenges, as much as sheer volume that we are talking about when we refer to “big data”. Not only is this far beyond the capacity of the best human brain to process in any acceptable timeframe, it requires advanced analytical software to identify and prioritise the most important events, almost literally to “understand what your building is trying to say to you”.

A whole range of suppliers are now active in this space, and some of them at least are likely to have a huge impact on how building automation develops going forward.

Here at BSRIA, in the latest regular update to our Hot Topic study on Threats to BACS Hot Topic for October 2013,  we focus on this area, as well as taking a look at the implications of another, less fortunate, consequence of the growing importance of IT and software in the built environment: the spectre of cyber-attacks on buildings.

Is this the Real Answer for Cheap Green Energy?

Ever since the first serious concerns were raised about man-made climate change a generation ago the world has been caught on the horns of a dilemma. The choice has too often seemed to be between securing the kind of short-term economic growth which the developed world expects and the developing world desperately needs  on the one hand, and paying more now in order to secure the future of our world on the other.

It is small wonder that green energy solutions are still seen as something of a luxury accessory, perhaps affordable in times of prosperity, but pushed into the background at times of world recession, when achieving growth and combatting fuel poverty becomes an even bigger concern.

But could it be that a large part of the answer is beneath our feet, or that at least it might be: an answer that could have a huge impact on the UK as it already has had in similar countries. For once I am not  talking about fracking, but about something that has been around for a century, though the technology continues to evolve in exciting ways.

The heat network rests on the fundamentally simple idea of producing heat (or cooling) centrally, in the most efficient and environmentally friendly way, and then distributing this through highly insulated underground piping, to homes, offices, hospitals, factories and anywhere else that needs it. Often this simply taps into heat that would otherwise be pumped wastefully straight into the atmosphere.

Different measures could radically affect the growth of Heat Networks in the UK

Different measures could radically affect the growth of Heat Networks in the UK

 Such networks not only distribute heat but can store it, for hours or potentially  months, ironing out the wild and often unpredictable fluctuations in both and supply and demand and making it much more practicable to use ‘green’ power sources, such as wind or photovoltaic that are inherently unreliable, not to mention biofuels. Even where gas is still used there is scope for greater efficiencies, especially where the opportunity is taken to use generated combined heat and power (CHP)

 So why is it that this technology accounts for only about 1% of the UK’s current heating needs while in Denmark, with an only slightly colder climate, the figure is over 60%. In fact most European countries already make much greater use of this resource than the UK does, as do countries as diverse as China, Japan and the USA.

In fact the benefits of district energy are already recognised by many UK hospitals, universities and industrial plants and office complexes, frequently powered by CHP systems which offer added security of supply. So why has the residential sector been so slow up until now?

Part of the answer lies in how the UK population lives: predominantly in individual houses which are more expensive to connect, and in most cases owner occupied or privately rented, making it much harder to convert individual householders to heat networks. The relatively low rate of house building in recent decades hasn’t helped either. Gas prices that are low by international standards have also reduced incentives to innovate in this direction.

However the last few years have seen a sea-change, with far more new homes tapping into heat networks, especially new flats, spurred on partly by enhanced incentives from government and encouragement from local planners, but also by a growing Energy Services industry that is prepared to make substantial investments in order to make a long term return.

Here at BSRIA we have recognised this trend, and so decided that a fresh look at the UK district energy market was needed. The result is a report which examines the market, the main players and what has drawn them into the market. It also considers the main positive drivers along with the biggest barriers to future development, and what can be learned from experience outside of the UK.

Our research indicates that the UK District Energy market is already worth over £400 million annually (including capital investment), and that it is growing at the fastest rate in its history, so that we expect it to exceed £500 million by

This blog was written by BSRIA's Henry Lawson

This blog was written by BSRIA’s Henry Lawson

2015).

The overview takes in different possible initatives on the part of national, and local government, as well as the EU, which could speed up development or hinder it, and at the key changes in technology which are likely to make a difference in future.

If you want to know how big this market is likely to be in two or five years’ time and what the prospects are for the future, then this should be an indispensible read.

To find out more about the report or to purchase it contact our Worldwide Market Intelligence team on 01344 465610 or wmi@bsria.co.uk

Choosing your BEMS

Wireless vs. wired – which is best?

Chris Monson, Strategic Marketing Manager of Trend

Chris Monson, Strategic Marketing Manager of Trend Controls

When installing a building controls system or building energy management system (BEMS), businesses want the most efficient, economical and environmentally friendly solution available to suit their requirements. But how should you choose between applying a wired or wireless connected control system? What’s the difference? And what are the benefits of each? Guest blogger Chris Monson of Trend Controls gives his opinion:

The cost difference

When it comes to making building control decisions, the major  factor for selection and installation apart from appropriate usage is usually cost.

The cost for installing wired or wireless systems is largely determined by two things: parts and labour. These are in turn influenced by the scale of the installation project. The larger the project, the more parts, time and budget you’re likely to need.

Whilst the parts for wired systems may be less than for wireless, wired system installation costs for time and labour are much higher when you factor in the additional costs for wiring and cabling. Because of this, wired solutions are best suited to smaller scale projects.

Conversely, a wireless system has only one fixed overhead – the main receiver module – no cabling or lengthy installation required. Numerous sensors can operate with one receiver module, making wireless the most cost efficient solution for large projects with four or more sensors. A typical example of savings:

  • 4 wireless sensors plus 1 receiver will cost 30% less than fitting 4 wired controllers and wiring them back to the receiver
  • 12 wireless sensors cost approximately 50% less than a wired system
  • Installing 32 wireless sensors would save over 60% of the cost of a wired system

The technical advantages

“Never mind the cost – which one will actually work better?”

If the cost is not a hindrance, the prime considerations for any project are basic funtionality and use. So what are the techinical advantages and disadvantages of wired and wireless?

Wireless temperature sensors contain a thermistor sensing element and transmitter. Both are encased in a standard wall mounting/plant type enclosure, and up to 50 sensors can interact with a single receiver unit. Remembering the advantages of wireless for large scale projects, a single receiver unit can be positioned up to 100m away from the sensors, so technically wirless can offer a very flexible solution. If correctly specified and configured, wired is a technical equal, and is not as susceptible to signal disruption. If disruption is a concern, most BEMS can be set to give and alert in the event of such a problem. ZigBee style networks are especially designed to avoid frequency disturbances and clashes with other devices, and were creared in the late 90’s when installers realised that WiFi and Bluetooth were not sustainable wireless solutions. As such, the mesh system uses 2.4GHZ radio frequency, making it flexible and reilient – if one node breaks, others in the circuit can still communicate.

Alongside cost advantages and ease of installation, using wireless systems offer another obvious, technological edge – wireless is wireless, instantaneous and also ‘plug and play’. This makes upgrading systems and introducing new technologies much simpler. Though regular maintenance such as battery changes need to be factored into the time/cost equation.

Deciding between the two

Before any decisions are reached, building should first be audited to determine the most suitable solution – it is advisable to test how well wireless signals can be received and how likely distrubances are. If this is an issue wired may be your only option. After this, choosing the correct BEMS system depends on the size and usage of the building, the scale of the project and company budget. As a general rule larger more extensive projects are typically best suited to wireless solutions.

This article was written by BSRIA member Chris Monson, Strategic Marketing Manager at Trend Controls in the UK.

Are designers keeping up?

BS EN 12464-1, Light and Lighting, Part 1 indoor workplaces, was first published in 2002. It included a schedule of recommended minimum task illuminances for a range of industrial, institutional and commercial applications. These values were similar to those previously in the Society of Light and Lighting Code. Originally the SLL values were ‘general’ illumination for the complete floor area thus enabling equipment and workers to be positioned anywhere in the space. A convenience when electricity was cheap.

However the BS specifically refers to ‘task’ illumination, normally only a small part of the gross floor area. The rest of the room would require less illuminance and thus considerable capital and operating cost savings can be made. But where are the task areas? Often the client has no idea when the lighting design is carried out. The designer then has to revert to ‘general‘ illumination to guarantee adequate lighting of the task. However the client will pay for the over lighting of the ‘non-task’ areas.

This problem of insufficient information is compounded by the changes included in the revision to BS EN 12464-1 last year. Introduced for the first time is the requirement for mean cylindrical illuminance in the space to provide good visual communication and recognition of objects. This should be no less than 50 lux, and for areas where good visual communication is important like offices, meeting and teaching areas not less than 150 lux. Although the concept of cylindrical illumination is not new it has not been widely considered for the routine lighting of workplaces.

How do many existing lighting schemes meet these new requirements? Very few published photographs of interiors include a full complement of ‘workers’ so there is little subjective evidence of how modern lighting affects the appearance of the human face. Accurate measurement could be a problem. Added to this is the same problem outlined above, the lack of occupational information of the space.

The Standard only considers the requirements of ‘workers’ so places where customers or visitors dominate lighting requirement need to be considered separately.

Are Compact Fluorescent Lamps welcome in your home?

Fluorescent lamp technology is certainly not new and when linear lamps became available after the Second World War their advantages were rapidly recognised by both industry and commerce so that by the 1970s fluorescent lighting had become a standard method of interior lighting for most buildings.

It therefore seemed reasonable that Compact Fluorescent Lamps (CFLs) introduced in the 1980s would be equally well accepted in the home by domestic consumers. However home users were not immediately impressed by the long-term savings, and were deterred by the high initial costs. Indifferent or poor colour rendering, physical incompatibility, mercury hazards, unfulfilled marketing claims and slow warm up were perceived as disadvantages.

 The arguments for and against CFLs became polarised and European governments decided to tip the scales by “banning” domestic filament lamps. Retailers meanwhile adopted “loss leader” pricing of CFLs and the popular national press reacted with health scares from mercury and ultraviolet radiation. The consequence was consumer confusion. However the argument has shifted with rising energy costs having a significant impact on domestic budgets and technological progress has addressed to some extent the earlier quality issues.

 There is now the opportunity to make a more rational judgement. Most information has been biased one way or the other. However there is now an independent and thorough assessment of CFLs that factually examines many of the issues and is well worth reading:

“An examination into the use of CFLs in the domestic environment”. James Thomas Duff (2011) has been published in the new CIBSE SDAR Journal for September. 

 No single lamp type can solve all lighting problems. The choice should be determined by the particular activities and thus the lighting needs of the occupants, rather than the architecture or design of the dwelling. Many building services operate in part to preserve the fabric and environment whereas lighting is only required when the space is occupied. As soon as it is vacated the lighting can, and should be switched off. Lighting is for the people, and the home is where personal character prevails. The choice is yours but hopefully it can now be based on sound facts rather than scare-mongering or “prohibition”.

Integrated working – is it the right time again?

For those of us who remember back to the early 1990s, the current drive of the Government’s construction strategy to get better value from construction by reforming procurement may seem like a case of history repeating itself (see The Latham Report “Constructing the Team”, 1994).

What is interesting to note is that both reports followed severe recessions in the construction sector which had themselves followed relatively long periods of growth in construction output. Of course this might be no more than coincidence, or it may be an attempt to embed some much-needed structural changes at a time when the industry is experiencing a buyer’s market, so that when times improve there is less tendency for the industry to revert to type.

I welcome the kinds of change that are now mooted: involving suppliers at the time they can add value to a project, which generally means earlier than usual; clients focusing on specifying output performance and designers/contractors working together to develop integrated solutions; supply chains engaged on serial orders that will encourage research and innovation.

We need more fundamental changes

I believe, however, that this will need a wider set of more fundamental changes to be put in place than just exhorting traditionally separate disciplines to work together. There are a number of hidden drivers that I suspect will also have to be tackled for this change to be effective.

These include the fragmentary nature of the client, the underlying power of the finance and insurance industries, and the tendency to think short-term.

A fragmented client comes from devolution of budgets, which itself promotes budgetary responsibility, but which also means that more organisations become occasional clients and don’t have the chance to develop the skills to deal with a sophisticated and confusing industry.

Finance and insurance underpin many of the choices made by developers and designers in terms of the technical standards they build into their schemes – no landlord wants to be left holding a difficult-to-let office block because the permitted floor loadings are outside the norm, irrespective of whether this capacity is ever needed. Manufacturers may feel the need to offer warranties to give their customers a safety net – difficult to achieve when a technology is new and may be favoured from an energy efficiency point of view.

Short term thinking is natural, but is often the enemy of good decision-making. It drives lower capital expenditure at the expense of higher operational costs. This may come from governments not seeing beyond the next election, or officials not seeing beyond their current posting, or organisations behaving as though they were not going to be around for more than a few years. Which is all understandable, but not really defensible. We have tools to help make good, long-term decisions – such as life-cycle costing – all we need to do is not be afraid to use them.

Integrated working for all supporting stakeholders

In my view, the desire for more integrated working must not be restricted to the primary members of the construction industry, but must also extend to all the supporting stakeholders and really engage with the operators and maintainers of buildings and infrastructure – a distinction which is unnecessarily perpetuated by the separation of CAPEX and OPEX budgets inside client organisations.

So, is it the right time for integrated working?

Taking lighting to task

For many years the conventional method of interior lighting for workplaces was by ‘general illumination’. As lighting was not expensive to purchase, install or operate, the principle was to provide illumination over the whole floor area with a high degree of uniformity. This enabled plants or furniture to be subsequently positioned anywhere in the space and easily moved without recourse to changing the lighting array.

Council House 2 - Offices. Spot the five sources of light....

 However for the past decade UK lighting codes and standards have recommended not ‘general’ but ‘task’ lighting. The significance of this change has either been ignored or gone largely un-noticed as the illumination values were basically the same. The new concept recognised that the main critical visual task is only carried out over a small part of the total floor area. The rest of the space is used for circulation, storage, filing and similar activities all of which are less demanding in terms of illumination. Lighting the whole area to the highest illumination required can use about a third more energy than matching the illumination to the different activities.

Energy costs are continuing to rise and therefore providing the right amount of light only where it is needed is beneficial both economically and environmentally. Also variation in illumination can make the space visually more interesting than overall uniformity. Normally the reason for still providing ‘general’ illumination is because the building is a speculative development and there is no client to determine the furniture layout, or simply that the layout has not been decided yet. I think potential tenants need to be aware that for lighting to be visually efficient the equipment should be electrically efficient and the lighting design should suit the activities across the space. Providing light where and when it is not needed is inefficient regardless of lumens per watt performance of the luminaires.  

Recommended illumination levels in the past were based upon the need to determine detail in the visual task, together with the amount of contrast critical nature of the work and the importance of colour discrimination. Recently there have been massive changes to how we read the written word with print on paper largely being replaced by self-illuminated screens of computers, tablets, telephones, information signs, cash registers, etc. At the same time there has been the move towards ‘hot desking’. No longer does a space have a constant lighting need. The visual task performed at any point will depend upon the occupant at any one time. Does this mean we should revert to general illumination?

Or does the lighting of our buildings require a fundamental rethink so it is more appropriate to today’s sometimes conflicting needs of energy conservation, use of electronic media devices and flexible occupancy of spaces?   Modern lamps have long lives and therefore lighting is only infrequently changed. Installations over twenty years old are not uncommon, a time span when most other electrical equipment will have been replaced several times. 

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