BSRIA relaunches Topic Guides

Construction compliance 3BSRIA is pleased to announce the relaunch of our information topic guides with the first release of this ‘At a Glance’ series TG07/2015 At a Glance – Airtightness available to download from the BSRIA website now.

The BSRIA Topic Guides are designed to be an at a glance publication introducing readers to key industry topics and suggesting further reading. BSRIA’s Information Centre is relaunching them with the aim of providing an introduction to key topics in the industry providing readers with an understanding of the area and how they can learn more. A new addition to the topic guides will be a feature by a BSRIA expert on the subject, offering a fresh insight. The airtightness topic guide features an insight into the legislation by our expert David Bleicher.

BSRIA’s Information and Knowledge Manager Jayne Sunley said ‘The topic guides are a great way of providing members and non-members alike with good information that will hopefully clarify some of the questions they have about topics they are new to, they’re not designed to be an all-encompassing guide but rather a starting point for anyone looking to learn more. The addition of the expert insight is just a way of showing readers that there is more to the topic than they might have first thought’.

TG07/2015 At a Glance – Airtightness offers readers a view of why airtightness is important for our building stock and how a building can be tested. It is now free to download from the BSRIA website for members and non-members alike.

Future 2015 titles in the At a Glance series will include Legionella, Data Centres and Smart Technology.

Have you been blackmailed by your Dishwasher? Who Owns the Smart Future?

This blog was written by BSRIA's Henry Lawson

This blog was written by BSRIA’s Henry Lawson

Having recently updated BSRIA’s key market studies on Building Automation Controls (BACS), Building Energy Management (BEMS) and Smart Evolution – towards the Internet of Everything, I was struck by a world in a state of flux with  implications for the built environment and technology in general that could be as profound as they are unpredictable.

The structure and make up of our buildings and cities have always been intensely political. The most visible of all human creations, they speak volumes about our abilities, our status and our values and our aspirations. I felt this last month  when viewing the ruins of Ephesus – once the second city of the Roman Empire –  as much as when  I am visiting London or Chicago.

At least since the turn of the millennium there has been a tacit assumption that while technology is the great enabler, much of the change in the way our buildings and cities are designed and organised will be driven by social concerns, typically expressed through politics. In particular, the perception that the threat of climate change requires far reaching action has led to a sustained series of targets, guidelines and regulations to increase both energy efficiency and the use of renewable energy, which naturally impacts on the built environment as one of the biggest consumers of energy.

Is this movement losing momentum? The financial crisis and recession affecting much of Europe, North America and some other parts of the developing world has proved to be the most prolonged since the 1930s. Even countries which appeared to escape the worst impact have since experienced either recession or a dramatic slowdown, including Australia, Canada and of course China.

With falling or stagnating production and rising government debt levels in so many countries, it is no surprise that finances and basic economics have come to the fore. Violent conflicts, especially in the Middle East, Africa  and Eastern Europe, but overflowing into other parts of the world, and in turn fuelling mass movements of refugees and economic migration are also seizing attention in developed countries as well.

All of this has sometimes appeared to leave the “green agenda” somewhat on the back foot. Even in countries like Germany, Austria, Australia and New Zealand, where Green parties have attracted mass support and had a major influence on government, they have seemed to become more marginalised. Britain’s recent elections resulted in a new majority government which has very quickly moved to relax requirements on the energy efficiency of new buildings, and also to phase out subsidies for wind power.

While there is argument as to how far this is simply a question of means, and how much it represents a shift in priorities, there is little doubt that measures to improve energy efficiency or to promote use of smart technology face an uphill path if they cannot also provide a quick pay-back.

Where governments get involved in technology, it tends to be for old fashioned economic reasons.  When  mega-corporations  like Microsoft, Apple, Google and Amazon have been in the spotlight it has mainly been because of accusations of anti-competitive practices or because of their tax policies. Rather less thought has been given to the ways in which companies like these could change the basic structure of society, the balance of power, and the whole environment.

Increasingly these global brands interact directly with a global audience, influencing their behaviour, and in turn being influenced by them. It is no accident that Microsoft, Apple, Google and Amazon, having established themselves as consumer brands, are now all active in the area of smart buildings, ranging from the smart home to, in Microsoft’s case, providing the data crunching to manage and optimise whole campuses of buildings.

Increasingly we can link these to wearable devices and to creators of virtual realities which could radically change our day to day activities and environment. Even the basic blocks  from which buildings are made can have ‘smart’ properties, from ‘self-healing’ bricks to glass that responds dynamically to different levels of light.

threatsWith artificial intelligence already surpassing human intelligence in certain well defined areas – such as chess playing – questions are raised about how far the technology goes, who owns it, and how much power they will have. Even our homes and offices can study, learn and predict our habits and our preferences, in ways that can certainly be useful, but also potentially disturbing.

For over a hundred years there have been fears about the prospect of vital areas of technology  being dominated by a single concern or perhaps a cabal of companies. So far, in practice, it has been innovation itself  that has come to the rescue. Even the most nimble footed technology giants have been caught off-guard by new waves of technology, from IBM, to Microsoft to Nokia. In the case of building technologies the requirements are particularly diverse, and  it is quite unusual to find a country where a single supplier accounts for more than 25%-30% of the market.

Nonetheless as we look to a future where corporations and, by implication, governments have access to information about almost every aspect of where we are, what we are doing, how we feel and what we want and fear.

While you can probably rest assured that your dishwasher probably doesn’t have a motivation to blackmail you (why were those extra glasses washed out at 3 o’clock last Thursday morning?) you can be less assured that it won’t soon have the evidence to do so.

More information about the latest editions of BSRIA’s market studies on Building Automation, Building Energy Management, and Smart Evolution is available here.

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.

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