Constructing the future is circulated in association with Contract Journal.

For £130 a year BRE Connect subscribers receive:– all BRE Digests, Good Building Guides, Good Repair Guides and Information Papers such as those listed on this page – totalling

at least 50 publications each year – all building to form an invaluable reference tool– a CD-ROM each year containing every BRE publication from that year in pdf format– preferential pricing on a range of BRE books and other publications – such as those listed on this page – for which subscribers pay

a significantly reduced price– discounts on a programme of BRE events. BRE Events are accredited to Continuous Professional Development (CPD).

For more information –Claire Allen, 01923 664761, Email ClaireAllen@emap.com

BRE Connect is a subscription scheme that gives unrivalled access to BRE’s expertise on buildings, construction, energy, environment, fire and risk.

Recent publicationsBooks

Working with the community: a good practice guide for the construction industry (BR 472)Identifies the impacts of construction projects on local people and businesses, and gives advice on how to mitigate some of the negative impacts. It will be a useful aid for anyone committed to improving the construction industry’s relationship with the public, particularly construction companies, developers, local authorities and clients. £35 (£22.50 for Connect members).

Geotechnics for building professionals (BR 473)An overview of ground behaviour and geotechnics focussing on shallow foundations for low-rise buildings. Aimed at architects, surveyors, loss adjusters, planners, insurance underwriters and property developers. £65 (£45 for Connect members).

Improving air quality in urban environments. Guidance for the construction industry (BR 474)Air quality is an issue that building design teams, developers and contactors increasingly need to consider. This publication focuses on outdoor pollution and sustainability, and provides guidance on addressing air quality issues during the building design and construction process. £40 (£25 for Connect members).

Green guide to composites: an environmental profiling system for composite materials and products (BR 475)Enables the composites sector to understand the environmental and social implications of different composite materials and manufacturing processes. The life-cycle impacts of each material and process choice from the cradle to the factory gate are presented in simple comparative rankings, allowing informed decisions to be made. Allows those involved in composite design and manufacturing to improve the sustainability performance of their products. £29.50 (£22.50 for Connect members).

DigestsConcise reviews of building technology.

Digest 491 Corrosion of steel in concrete: a review of the effect of humidityReviews recent models and data and presents supplementary information to EN 206 for the UK, based on industry practices and environmental data.

Good Building GuidesPractical guidance on building design and construction.

GBG 63 Climate ChangeConsiders how the climate is changing, the potential risks this will bring to buildings and, as a consequence, how building design and construction will need to change.

Information PapersThe latest BRE research information and how to apply it.

IP13/04 An introduction to building with Structural Insulated Panels (SIPs)SIPs - a modern method of construction that is becoming increasingly popular for use for primary loadbearing components. This Paper gives information and advice on the design, construction and performance of the generic form of SIPs used primarily for domestic and light industrial construction.

IP14/04 Environmental sustainability in bridge managementEnvironmental performance is increasingly seen as a principle against which bridge management should be measured, but a comprehensive understanding of the environmental impacts does not yet exist. Surrey County Council is collaborating with BRE on an assessment method for the environmental comparison of bridge management strategies. This Paper is an output of that collaboration.

15 March 2005 in LondonDesigning for sustainabilityAn event on implementing a sustainable approach to architecture to meet client needs. Contact: 020 7505 6044, constructconferences@emap.com

16 March 2005 at BRE, WatfordTimber quality grading and scanningContact: Tim Reynolds, reynoldst@bre.co.uk

22-23 March 2005 at BRE, WatfordEcoHomes assessor training courseA two-day course covering the technical content of EcoHomes and the details of the assessment process. Contact: 01923 664462, breeam@bre.co.uk

11-15 April 2005 at BRE, WatfordBuilding services integration with EIBEuropean Installation Bus (EIB) technology delivers building performance through building services integration, reducing energy costs, enabling remote management and introducing life style benefits. This five-day course allows delegates to effectively deliver the benefits of EIB, and provide value-added service to clients. The course provides them with an understanding of the key elements of design, installation and commissioning of EIB systems.

13-14 April 2005 at BRE, WatfordBREEAM Offices assessor training courseTwo-day training course to become a BREAM for Offices assessor, covering the technical content of BREEAM for Offices and the details of the assessment process. Contact: 01923 664462, breeam@bre.co.uk

26 April 2005 at BRE, WatfordIntroduction to BREEAM and EcoHomesHalf-day seminar providing developers, clients designers, and contractors with an overview of the principles of sustainable construction, and demonstrating how the BREEAM and EcoHomes environmental assessment schemes can help them to meet their sustainable construction targets.

27 April 2005 at BRE, WatfordCable testing and certification seminarDetails to be announced.

6-9 June 2005 at BRE, WatfordOFFSITE2005A major exhibition and conference that will demonstrate the ability of offsite and other modern methods of construction (MMC) to deliver quality homes, schools, hospitals and commercial buildings that are creatively designed, energy efficient, sustainable and cost effective.

13-15 September 2005 at BRE, Watfordresource05Major energy efficiency, low carbon and renewable technologies conference and showcase. See www.resource05.com

Further informationFor further information on these events and training courses contact (unless otherwise stated) BRE Events – 01923 664800, email events@bre.co.uk or visit www.bre.co.uk/events

PricesDigests and Good Building Guides are £12 each (£8 for Connect members). Information Papers are £9 each (£6 for Connect members).

Where to get themThese publications are available from:- www.BREBookshop.com- Phone 01344 404407- Fax 01344 714440- Email BREBookshop@IHSRapidoc.com

Diary of forthcoming events24 February 2005 in Birmingham2 March 2005 in Nottingham3 March 2005 in Cambridge9 March 2005 in LondonRecycled roadsThe benefits of using recycled materials in highway and street maintenance are being demonstrated in this series of highly interactive, practical ‘recycled roads’ workshops being run by WRAP (the Waste & Resources Action Programme).

24 February 2005 in Manchester10 March 2005 in Bristol18 March 2005 in LondonAchieving Whole Life Value in Infrastructure and BuildingsICE, CIRIA, BRE and TRL have been (with DTI funding) developing a Guide to Achieving Whole Life Value in Infrastructure and Buildings, which give practical steps to unlocking whole life value to those who own commission, design and deliver infrastructure and building projects. The outcome of this work is being presented at regional events – delegates will each get a copy of the guide.Contact: Mary Treen, 01344 770514, conferences@trl.co.uk

9 March 2005 at BRE, WatfordFire safety of productsThis one-day course provides a general introduction to Fire and the Fire Testing of Plastics, Rubbers and Textiles. It describes the effects of fire parameters on burning behaviour, the various types of fire tests and their selection to specifiy materials and products of reduced flammability.

9 March 2005 at BRE, WatfordSmart homes need smart controlsA one-day workshop describing the benefits of the European Installation Bus (EIB) - one of the market leaders in European integrated home control systems with over 100 manufactures producing EIB compliant devices – focusing on applications and giving a practical insight into technical operation.

11 March 2005 at BRE, WatfordFire, impact and weathertightness performance testing of building envelope systemsSeminar to discuss the second edition of BR 135 Fire Performance of External Thermal Insulation for Walls of Multi-Storey Buildings, and the issues related to the fire performance of external cladding systems.

FEBRUARY 2005 ISSUE 23

Unlocking Innovation Modern methods of constructionChanges to guidance for concrete in the groundAirtightness in large buildings Disability Discrimination ActPhotovoltaics field trial – initial results

CONSTRUCTING THE FUTURE

02/05

Construction innovation threatened

Central government funding for research and innovation in UK construction has changed markedly over the last year or so. Significant and urgent action is needed by the construction industry and its research providers, if irreparable damage to our technical knowledge, and ability to innovate and contend with overseas competition, is to be avoided.Government funding for construction R&D through the DTI Partners in Innovation scheme has been scrapped, along with other industry-sector-based schemes. Now, all sectors must win public funding from a single pot of money available for research and innovative technologies within the DTI. This may seem fair enough, but the Construction Industry Council and others are asking how construction is going to compete against seemingly more glamorous and high-tech sectors, such as the automotive, IT, pharmaceutical and telecommunications industries. Not only do industries such as aerospace appear to offer more exciting opportunities for innovation, but they are also often dominated by a handful of very large and influential companies that can speak for their industry with one powerful voice. Construction by comparison, though a vast industry employing 2 million people and accounting for 10% of the UK’s GDP, is composed of a multitude of smaller companies that find it difficult to unite and effectively fight for their sector. These challenges occur at a time when the need for innovation in construction has seldom been greater. Millions of new and affordable homes are wanted and vast public building programmes are underway – all in the face of serious skills shortages and pressing demands for sustainable resource use. As well as establishing a single voice for the industry, strong enough to win vital R&D funding, construction must be proactive in developing and implementing new innovations within the sector. And we must look at other industry sectors for innovations that can be adapted and applied in our own.We must demonstrate to government our ability to deliver significant improvements in competitiveness and sustainability through innovation. We have a new, if challenging, opportunity to win public funding to support the next generation of technologies that will deliver step changes in performance, sustainability and value in construction.I would like to hear from construction companies and other organisations looking to differentiate themselves with innovative approaches. By working together, we can show government that the construction sector can be innovative and is deserving of its support.

Peter BonfieldManaging Director, BRE ConstructionEmail bonfieldp@bre.co.uk

Contents

Comment 1Overview: news. 2Unlocking innovation: innovative solutions to apparently intractable problems can come from unexpected sources, even from a small African beetle. 5Modern times, modern methods: the challenges presented by demands for huge numbers of new homes, and by massive public building programmes, are unlikely to be met with traditional construction methods alone. 7 Changes to guidance for concrete in the ground: new information on factors contributing to sulfate attack of concrete in the ground has prompted a revision of a key guidance document. 9Airtightness in large buildings: demonstrating the required airtightness of a very large building is a highly complex task. 11 Disability Discrimination Act (DDA): the final stage of the DDA 1995, Part III, Access to Goods, Facilities and Services, came into effect on 1 October 2004. 12Photovoltaics field trial – initial results: detailed information on the design, installation and performance of photovoltaic systems installed in 217 homes across the UK is being gathered in a six-year field trial. 13

OverviewComment

Constructing the future is published by BRE, the UK’s leading centre of expertise on the built environment, construction, energy use in buildings, fire prevention and control, and risk management. BRE is owned by the BRE Trust, a registered charity with a mission to champion excellence and innovation in the built environment for the benefit of all.For a free subscription to Constructing the future telephone 01923 664303ISSN 1465-3788

Editor: Tom Harvey, E harveyt@bre.co.uk BRE: www.bre.co.ukDesign: OPX, London, T 020 7729 6295, www.opx.co.ukPrinting: Croxsons Sheetfed, T 01923 692500, E info@croxsons.co.uk

Industry supports MMC showcase

Several leading modern methods of construction (MMC) exponents have announced their sponsorship of the MMC showcase, OFFSITE2005. Sponsors now include: The Concrete Centre, English Partnerships, Hanson, the Insulating Concrete Formwork Association, Mtech, Ruukki, Scottsdale Construction Systems, Terrapin and Van Elle.

As well as sponsoring the event, they will be among the wide ranging MMC companies presenting full-scale, interactive demonstrations and displays at OFFSITE2005 from 6 to 9 June 2005 at BRE, Watford.

Jointly organised by BRE and SmartLIFE, OFFSITE2005 will demonstrate MMC’s ability to deliver quality homes, schools, hospitals and commercial buildings that are creatively designed, energy efficient, sustainable and cost effective.

The demonstrations will be combined with a daily programme of seminars. These will cover technical aspects, regulations, certification and quality, along with the global opportunities and applications of MMC, their contributions to sustainable communities, and the issues of accelerating delivery through partnering and developing the modern workforce.

‘We are proud to be a main sponsor of OFFSITE2005,’ says Vic Handley, Group Business Development Director of Van Elle. ‘The event gives us an outstanding opportunity to reinforce our commitment to modular foundation construction.’

Van Elle also sponsored OFFSITE03, the first event of this kind in the UK, which attracted more than 3000 visitors in May 2003. ‘At OFFSITE2005 we will again be exhibiting our Smartfoot® precast modular foundation system, and officially launching our unique Litefoot® foundation innovation.’

‘Ruukki will use OFFSITE2005 to demonstrate our factory-assembled, building envelope system modules,’ says Chris Wright, Ruukki’s UK Marketing Consultant, ‘which arrive on site in one piece and are simply fixed in place, cutting construction time and installed costs.’

According to Tim Mason, Terrapin’s Commercial Director, ‘Terrapin chose to sponsor OFFSITE2005 as this event provides the ideal venue for client organisations and specialist suppliers to meet and discuss the benefits of off-site construction.’

Anyone wishing to sponsor, exhibit at or attend OFFSITE2005 at BRE, Watford on 6-9 June 2005 should visit www.offsite2005.com, call 01923 664766 or Email offsite2005@bre.co.uk

Part P – electrical safety

Most electrical installations in homes are now (from 1 January 2005) covered by Approved Document P of the Building Regulations 2000. Part P also applies to electrical installations in common access areas in blocks of flats such as corridors and staircases, and to any shared amenities such as laundries and gyms.

The new regulation means that all householders needing electrical work, many of whom remain unaware of the new requirements or are unclear of their implications, must either:

– employ an electrical contractor who is registered as a ‘Competent Person’ to Part P of the Building Regulations – for a full list see www.partp.co.uk, or

– let the Local Authority Building Control office know of their intentions to carry out electrical work – Building Control will inspect the work.

Part P defines an electrical installation as 'fixed electrical cables or fixed electrical equipment located on the consumer's side of the electricity supply meter'. This includes all wiring and assemblies other than portable or transportable appliances. The vast majority of this type of work is likely to be covered under Part P by Competent Persons rather than Building Control.

BRE Certification has government approval to run a Competent Person Self-Certification Scheme for Part P, which has been developed in collaboration with the Electrical Contractors Association (ECA) and with the support of the Institution of Electrical Engineers (IEE). The website www.partp.co.uk provides information on how to join the scheme. Once a company has been approved, it is subject to annual surveillance visits to ensure continued quality service.

For further information – T 01923 664100Email enquiries@brecertification.co.uk

Assessing non-traditional housing

Comprehensive guidance on identifying and assessing more than 400 types of non-traditional housing – homes constructed with precast or in-situ concrete, or metal or timber frame – has recently been published.

For each house type listed by name (and alternative names), the book provides a photograph, identification characteristics such as materials used for walls and roofs, descriptions of construction elements and variations, and details of the when and how many were built. There is an accompanying CD ROM containing a search engine for locating house types.

Notes on potential faults are provided, based on 20 years of BRE investigations of non-traditional housing, and thirty ‘designated defective’ house types are clearly identified. Cut-away isometric construction drawings are keyed by number to detailed construction notes, and there is thorough referencing to lists of reports and journal articles for further information.

Phil Hallman, an advisor to the Building Research Housing Group* (BRHG), says, ’This book has been eagerly awaited by BRHG because of its great value to housing maintenance teams. In fact, BRHG members were foremost among the local authorities and housing associations that returned questionnaires gathering data on housing types, numbers owned and changes done and planned.

‘In addition, BRHG sponsored the production of the book, knowing that it will help to answer such questions as whether reinstatement of a non-traditional house of any type is possible and can be justified.’

Non-traditional houses: Identifying non-traditional houses in the UK 1918-75, is available from BRE Bookshop, www.BREBookshop.com, or

T 01344 404407, Email BREbookshop@ihsrapidoc.com* BRHG members, in partnership with BRE, address enquiries

through their website www.brhg.org.uk on the full range of tasks associated with social housing provision.

£30 billion construction opportunity

A conference addressing the construction issues involved in the Building Schools for the Future programme is being held on 3 March 2005.

Described by Tony Blair as ‘the greatest schools renewal programme in British history,’ the £30 billion Building Schools for the Future programme to rebuild or refurbish every secondary school in England will have a huge impact on the construction industry.

Contractors, suppliers, offsite manufacturers and other construction industry professionals will be at the forefront of delivering this massive programme of work over the next 15 years. To help them to make the most of this opportunity, a conference on gaining access to the programme is being held on 3 March 2005 at BRE, Watford.

Unlike other events focussing on Building Schools for the Future, this conference will specifically address the hard construction issues involved and engage the construction supply chain. It will look at:

– how the programme works– how contractors, manufacturers and

suppliers can get involved– the lessons learned from those already

involved in the programme– accessing the funding and financial

implications.

Leading speakers from the DfES and Partnerships for Schools will brief delegates on the progress and priorities of the programme. Pathfinder and Wave One LEAs will present their flagship schemes, and offsite construction experts will showcase the latest developments in modern construction methods. In addition, a leading architect will demonstrate how innovative design can transform the educational environment.

For further information – T 01923 664800Email events@bre.co.uk

01/02

Fire safety research

José Torero has been appointed as the first head of the national Centre of Excellence in Fire Safety Engineering, and holder of the new BRE Trust/RAE Chair of Fire Safety Engineering at the University of Edinburgh.

The new Centre of Excellence has been established by the University of Edinburgh and the BRE Fire Division (FRS). Based at the University and headed by the new Chair (which is jointly funded by the BRE Trust and the Royal Academy of Engineering), the Centre aims to bring a fresh research and educational impetus to fire safety engineering.

‘During the last fifteen years, fire safety research and education has been so disjointed that we have lost our focus when pressing for government and industrial commitment,’ says José Torero, ‘and as a result priorities have been placed elsewhere.’

Professor Torero came to the University of Edinburgh as a Reader in Fire Dynamics in 2001, from the University of Maryland where he was an Associate Professor at the Department of Fire Protection Engineering, and an Affiliate Associate Professor at the Department of Aerospace Engineering.

‘We believe that the new Centre of Excellence will provide the critical mass needed to give fire safety research and education a strong voice,’ says Professor Torero. ‘Strong enough to bring their importance to the attention of government and industry.

‘My job is to bring together the world-class activities of the University of Edinburgh and FRS in a way that will revitalise fire safety engineering.’

‘Establishing a Centre of Fire Safety Engineering will give fire research a much needed boost,’ says BRE’s Chief Scientist, Professor Farshad Alamdari. ‘This is just the first in a number of Centres of Excellence that the BRE Trust will be supporting.’

For more information – Professor Farshad Alamdari, 01923 664947Email alamdarif@bre.co.uk

Too hot to handle?

Maintaining air temperature at a suitable level in server rooms can present serious difficulties for building managers and service engineers. The root of the problem is the ever-increasing heat load generated by IT equipment.

‘These days minimum computer loads can be as high as 20kW for a typical high-end server cabinet,’ says David Butler who runs BRE’s large Environmental Test Chamber. ‘Whilst there are ways of dealing with cooling at this level, a number of issues need to be considered and the solution is rarely as straightforward as it may first appear.’

The traditional approach of placing server cabinets in parallel rows to create hot and cold aisles with cold air supplied from the floor void, only works with output of around 6kW. Beyond that, the footprint of the server rooms needs to be increased and in some instances this just may not be possible. An alternative approach is to introduce higher-capacity cooling systems but these, by their very nature, will generate more heat and thus increase the risk of damage if there is failure. Water-cooled cabinets can provide an effective solution but many are wary of the potential damage that would be caused if water were to leak through to the servers.

‘Reliability is crucial when the stakes are high as they are with IT,’ says David Butler. ‘In these cases, it can be worth spending a little time and money assessing the performance of the chosen system before finalising the decision. Over the past couple of years we have been asked to assess a number of cooling systems in our environmental test chamber. In each case there has been some shortfall or failure that neither we nor the design team could have predicted. Once the problem has been identified, the design team can refine the system until it can be seen to cope with the cooling targets.’

Energy efficiency is another issue that will become increasingly important. ‘With the Energy Performance of Buildings Directive coming on stream next year and further changes to Part L in the pipeline,’ says Butler, ‘designers will need to meet energy consumption targets as well as ensure system performance. There will be a real incentive to look for longer term solutions that will meet future technology improvements.’

For more information – BRE Environment, 01923 664500Email environment@bre.co.uk

News from BRE Certification

2005 Red BooksThe January 2005 editions of the Red Books are now out. These list fire and security products, systems and services plus construction products and environmental profiles. Each year the number of new companies and products increases and the 2005 edition is no exception.

As the Red Book is already out of date by the time it is printed, it’s worth remembering that a live copy of the list is available at www.RedBookLive.com – this is proving a very popular service with over 373,000 hits recorded for November 2004. The first quarter of this year will see improved web search functions, and Red Book listed companies now have a facility to add data sheets to their live entries.

RooflightsAs recently reported in the trade press, the Health and Safety Executive is calling for fragile rooflights to be banned in all new buildings as they pose a danger to construction workers.

LPCB already offers approval of the security element of rooflights (LPS 1175) but readers may be interested to note that BRE can offer tests to ACR(M)001:2000 Edition 2 Tests for fragility of roof assemblies. For more information – 01923 664100.

Environmental ProfilesArmstrong Building Products has recently received Certification for environmental profiling of their ‘Armstrong suspended ceiling system’. The product also achieved an ‘A’ rating via the BRE Green Guide to Specification.

BRE Certification’s Environmental Profiles scheme has been established to allow product manufacturers to demonstrate the environmental performance of their products. Environmental profiles may be calculated for materials, components and building elements. For more information see www.RedBookLive.com.

Fire Growth TestsLPS 1181:2004:Part 4 – Series of Fire Growth Tests for LPCB Approval and Listing of Construction Product Systems, the latest part of the LPS 1181 series of Loss Prevention Standards, is due to be published early in 2005 and will appear on www.RedBookLive.com shortly afterwards.

Part 4 is based on the BS 8414 test series and covers requirements and tests for external thermal insulated cladding systems including rendered, brick slips or similar finishes (ETICS) as well as rain screen cladding systems applied to the face of a building. The test is intended to represent the action of a fire exiting a window opening and flames impinging on the external surfaces of the cladding systems.

LPS 1175 approvalsBradbury Security has gained approval to LPS 1175 – Specification for testing and classifying the burglary resistance of building components, strongpoints and security enclosures, for their Fortress 2 security door. This is the first fully louvred door to receive LPCB approval.

Selectaglaze has gained approval to LPS 1175 for their Series 50 Level 1 and 2 products. These secondary glazing units are the first commercial windows to be approved by LPCB to LPS 1175. This approval shows that, with careful design, approval of glazing products to LPS 1175 is indeed possible.

Both the above approvals confirm the widening range of products that can be approved to LPS 1175 including cladding systems; fences and walls; fixed grilles; folding doorsets; garage doors; roofing systems; sheds and tool stores; sky lights; strongpoints and enclosures; temporary buildings; vehicles and windows.

LPS 2020 Suite of StandardsDevelopment drafts of BRE Certification’s new suite of standards for manufactured building systems, LPS 2020, were circulated to stakeholders in November 2004. Three consultation workshops were held on 13 and 15 December 2004 involving manufacturers, housebuilders, architects, insurers, mortgage lenders, Government agencies and other interested parties.

The standards were examined in detail and a number of changes proposed. The calibration stage was launched in Manchester at the ODPM’s Sustainable Buildings Summit at the end of January 2005. For more information – Jaya Skandamoorthy, 01923 664582Email skandamoorthyj@bre.co.uk

Sustainability tools

EcoHomes updateA new credit rewarding the use of zero-emission energy sources in housing has been added to the EcoHomes scheme as part of its 2005 update.

The credit encourages the use of locally generated renewable energy sources, such as solar photovoltaics and wind turbines, to supply at least 10% of a development’s heating and electricity. This will not only lead to reduced emissions of greenhouse gases and other pollutants, but will also help to conserve fossil fuels and develop a market for renewable technologies.

EcoHomes (part of the BREEAM portfolio) assesses dwellings against a range of environmental issues with credits awarded for good environmental performance – the more credits achieved, the better the final rating. Its success lies in the fact that it provides the marketplace with a balanced approach to sustainable development, looking at both the design and operation.

‘EcoHomes does not demand the “perfect” solution,’ say Cecilia Bagenholm of BRE, ‘but promotes a process of continuing environmental improvement, encouraging use of the latest technologies, construction methods, and best practice design principles. The scheme strives to achieve this in a cost-effective and practical way, ensuring market appeal and giving individual buildings recognition where they perform well.’

Regular courses are run for those interested in becoming EcoHomes assessors. Details are available at www.bre.co.uk/events.

For further information – BREEAM Office, 01923 664462Email ecohomes@bre.co.uk

BREEAM for schools BREEAM Schools has been added to the BREEAM portfolio of environmental assessments. The new scheme will help schools and LEAs to set environmental targets for new and refurbished buildings, and will help designers to improve the environmental performance of school buildings.

‘The Government is linking the largest schools capital investment programme since the Victorian era with education reform, to provide flexible, inclusive, attractive learning environments that teachers want to teach in and pupils want to learn in,’ said David Miliband, who was School Standards Minister when BREEAM Schools was launched (he is now Minister of State for the Cabinet Office).

‘It is important that such investment also provides a key opportunity for reform and innovation in school design, improving the environmental performance of our schools and realising the many benefits of more sustainable buildings. We are therefore delighted that the new BREEAM scheme is ready to run.’

The development of BREEAM Schools was funded by the Department for Education and Skills (DfES). The new scheme replaces the Schools Environmental Assessment Method which was published in 1995, and was launched in October 2004.

For more information – BREEAM Office, 01923 664462Email BREEAM@bre.co.uk or visit www.bre.co.uk/BREEAM

In brief

Recycled roadsThe benefits of using recycled materials in highway and street maintenance are being demonstrated in a series of highly interactive, practical ‘recycled roads’ workshops being run by WRAP (the Waste & Resources Action Programme).

Focused on increasing the specification, procurement and use of recycled and secondary aggregates, the workshops are aimed at local authority highway engineers, their consultants, contractors and suppliers.

Six of these free workshops have successfully taken place around the country, and four more will be held at:

– Birmingham on 24 February 2005– Nottingham on 2 March 2005 – Cambridge on 3 March 2005– London on 9 March 2005.

To register – 01344 770514, Email conferences@trl.co.uk

Indoor air qualityAir quality is an issue that building design teams, developers and contractors need to consider when they are planning new developments or major refurbishment projects. Responding to growing air pollution in urban areas, local authority, planning and environmental health departments are increasingly demanding that those specifying, designing or constructing buildings should minimise pollution – both that emitted during construction and as a result of the building’s use, and that infiltrating the building. Recently published guidance introduces some of the air pollution issues that building design project teams need to be aware of.

Indoor air quality in urban environments – guidance for the construction industry (BR475) can be purchased from www.BREBookshop.com, or Tel: 01344 404407, email BREbookshop@ihsrapidoc.com

Designing for sustainabilityRecent revisions to Part E and Part L, and the potential impact on building regulations of the Sustainable and Secure Buildings Act 2004, are among the issues increasing the need to address sustainability in building design. Client pressure to produce sustainable designs, and architect practices’ own aspirations, are also pushing architects to take sustainable design seriously.

A seminar on designing sustainable buildings is being held on 15 March 2005 at RIBA, London W1

For more information – T 020 7505 6044 Email constructconferences@emap.com

Whole life value in infrastructure and buildingsExperts from ICE, CIRIA, BRE and TRL have been carrying out a DTI funded research project to develop a Guide to Achieving Whole Life Value in Infrastructure and Buildings, which gives practical steps to unlocking whole life value to those who own commission, design and deliver infrastructure and building projects.

The outcome of this work is being presented at regional events that will include presentations on the whole life value concept, case studies demonstrating application of the principles, and question and answer sessions – delegates will each get a copy of the guide. The events are on 24 February in Manchester, 10 March in Bristol and 18 March in London (an event in York was held on 10 February).

For more information – Mary Treen, 01344 770514Email conferences@trl.co.uk

Gilli Hobbs of BRE with the Environment Minster, Elliot Morley, and the Biffaward trophy for waste minimisa-tion awareness raising.

” It is important that such investment also provides a key opportunity for reform and innovation in school design...”

David Miliband

Award winning waste GISBREMAP, a geographical information system (GIS) that helps construction firms deal effectively with waste, won the Awareness Raising/Education on Waste Minimisation Category at the Biffaward Awards 2004.

BREMAP combines information on recycled products, landfill sites, transfer stations, incinerators, recycling sites, reclamation companies, composting facilities and manufacturer take back schemes, in a simple, web-based format.

Presented on maps accessed via www.smartwaste.co.uk by typing in an appropriate post code, this information allows firms to reduce transport of bulky waste by locating the nearest, most suitable waste management site. It also highlights the availability of recycled or reclaimed construction materials and products in the vicinity of any site in the UK.

Gilli Hobbs of BRE who received the Award said, ‘This will greatly help to promote our BREMAP service, which turns map based information into construction and demolition reuse and recycling, whilst encouraging minimum road miles.’

For more information – Gilli Hobbs, 01923 664856Email hobbsg@bre.co.uk

03/04

UNLOCKING INNOVATIONInnovative solutions to apparently intractable problems can come from unexpected sources, even from a small african beetle.

of a solution nor the research outfi t likely to provide it, see Inventa as a possible threat.

It was the fact that they were not trying to muscle in on either party’s patch that allowed Inventa to get where they did with Stenocara. The company derives its income from consultancy and success fees.

Construction solutionsInventa has particular knowledge of the defence sector, where innovation technology is often ahead of the commercial fi eld and provides considerable scope for transfer to other sectors.

Ground penetrating radar invented by the British Army to detect plastic mines in the Bosnian war, is one example. Now declassifi ed, the radar’s potential for fi nding hidden pipes and cables beneath building sites will be tested.

Inventa recently entered into a collaboration with BRE – which has extensive technical expertise and knowledge – to help construction industry companies gain greater commercial success from both their own innovative ideas and practices, and the latest research and development in the construction and other sectors.

With the UK research and development base valued at more than £60 billion, there is considerable scope for greater development of new products and processes. But fi nding new ways to access technical solutions, and create new and improved products on the back of them, can require companies to invest signifi cant time and money. It is for this reason that BRE and Inventa Partners have created the Innovation Discovery Programme, a unique approach to enabling companies to unlock innovation effi ciently and effectively.

‘The problem for UK product manufacturers is that when they carry out research and development themselves, they need to claw back the investment in the prices they charge’, says Gideon Davenport. ‘That makes new products more expensive and customers may be unwilling to pay a premium – this can stifl e innovation. BRE and Inventa will look across the existing research base (within the construction industry and outside) to see if there is anything that can be applied to our clients’ problems.’

Innovation discoveryThe BRE/Inventa partnership’s Innovation Discovery Programme comprises four phases:

1. Innovation strategy: identifying areas of a client’s business or products that would most benefi t from technological innovation.

2. Technology discovery: detailed briefi ngs with technology partners, such as materials scientists and process specialists, to access information on ‘disruptive’ technologies. A ‘Technology Discovery Report’ will set out the best solutions, prioritised according to agreed assessment criteria.

3. Commercial and technical due diligence: the partnership brings a wealth of management and commercial experience, along with signifi cant technical understanding, to help clients with the due-diligence process for a project, opportunity or ‘new’ technology. It may even be able to suggest more appropriate ‘alternative’ technologies to meet a client’s commercial objectives.

4. Technology adoption: In all technology transfer negotiations there is an ‘imbalance of bargaining power’ between the technology acquirer and the technology owner. This is exaggerated by misaligned or misunderstood objectives, which are often hampered by confused communication. Through its extensive management experience the partnership can bring an understanding of both perspectives, and the communication issues and commercial assumptions encountered, to help mediate a successful transaction for both parties.

For further information on this initiative to bridge the gap between research and development, and commercial and competitive success, contact:

Matt Dickinson of BRE – tel 01923 664658, Email innovation@bre.co.uk, or Howard Mapperley of Inventa Partners – tel 01962 888522, Email hmapperley@inventapartners.com

ReferencesAndrew Parker and Chris Lawrence, Water capture by a desert beetle, Nature 414, 33-34, 1 November 2001.

Eamon Rafferty, How a beetle became the mother of invention, Financial Times, 2 December 2004.

It hardly ever rains in the Namib Desert of Namibia in south-west Africa, yet a beetle called Stenocara thrives in this apparently waterless region.

The secret of Stenocara’s success is its ability to capture water from occasional fog-laden winds. Researchers from Oxford University and QinetiQ (the former Defence Evaluation and Research Agency) studied Stenocara’s shell, which is covered in bumps. They found that the bumps’ peaks are smooth like glass and attract water, while their slopes and the troughs between them are covered with water-repelling wax.

As the early-morning fog sweeps across the desert, water sticks to the peaks of the bumps, eventually forming droplets. When the droplets become large enough, they roll down from the peaks and are channelled to a spot on the beetle’s back that leads straight to its mouth.

Technology transferUnsurprisingly, the researchers started thinking about using this natural technology to bring water to people in arid regions – tent coverings and roof tiles that could collect water for drinking and agriculture, for example.

Another use for Stenocara’s extraordinary ‘skin’ came to light during a meeting attended by Gideon Davenport of Inventa Partners (a technology innovation consultancy based in Hampshire) and executives from a company that makes water towers for offi ce blocks, designed for cool air-conditioning systems. The company had come to Inventa to see if it could solve the problem of water evaporation from the towers, which is expensive to remedy.

Having heard the Stenocara story some while before, Davenport re-told it at the meeting – and the fact that scientists had been developing an artifi cial material that mimics the beetle’s shell structure.

He suggested that this might provide an answer to the problem. Now, the water tower company and a rival are in discussions to licence the technology from QinetiQ, which developed the material.

This means sealed, non-evaporating water towers could soon be in production at a saving of about 20% on current costs. In recognition of this work, Inventa and QinetiQ jointly won last year’s building services industry ‘Bright Spark’ award.

The water tower example typifi es Inventa’s approach – it does not involve itself in trying to own or licence the technology that is being transferred, or take a stake in the company that wants to use it. This means that neither the company in search

05/06

MODERN TIMES, MODERN METHODSThe challenges presented by demands for huge numbers of homes, and by massive public building programmes, are unlikely to be met with traditional construction methods alone.

It seems that conditions are right for off-site manufacture and other modern methods of construction (MMC) to enter – or become – the mainstream. A combination of acute building need, skill shortages, regulatory pressures and affordability has created a climate in which traditional construction is no longer the most appropriate option in many situations.

Affordable housingMany of the companies and organisations involved in off-site and MMC have their attention focused on the housing sector, where government’s call for hundreds of thousands of new homes is still to be answered. With a large proportion of these earmarked as affordable and key worker accommodation, there is scope for the repetition that makes modular and volumetric construction cost effective.

Volumetric manufacturer Spaceover built a prototype block of apartments in south London in response to ‘Keep London Working', a key-worker research and development project managed by Peabody Trust. The project aims to develop self-contained fl ats that can be built in large numbers for less than £1100 per sq m – exclusive of land – to rent at between £85 and £135 per week.

The Barons Place development comprises three one-bedroom live/work, and three two-bedroom ‘sharer’ apartments, made of a total of 15 modules, built over three storeys. Each 18 or 25 sq m module has a rigid welded modular frame, with all services positioned in external ducts/cupboards to allow easy connection (and disconnection).

Internally, the apartments come fully fi tted with a complete range of white goods, between 1.6 sq m and 4 sq m of full height fi tted cupboards, electric underfl oor heating below a wood veneer fl oor, and a pre-fabricated, component based shower/wc room. Because all the services – including cisterns, controls and connections – are housed outside the main body of the fl at, the interiors are uncluttered and feel spacious, despite being quite small.

Thorough technical development work and close co-ordination between the manufacturing and site operations resulted in a fi ve-month building programme that went very smoothly:

- work started simultaneously on and off site in March- the modules were delivered and erected over one weekend in late April- the building was largely completed by August- tenants moved in during October.

Student accommodationWhilst concrete is often forgotten in off-site/MMC discussions, two concrete construction techniques – Tunnelform and Crosswall construction – are accepted as MMC, and both have increased in popularity in recent years.

‘The industry uses very modern methods to form the concrete,’ says Andrew Minson, head of framed buildings at the Concrete Centre, ‘with low-labour, highly mechanised ways of producing units that perform very well in terms of sound, and are very robust and very durable.’

Tunnelform construction is being used in a number of hotels and student residences throughout the UK. It is a modular method using in-situ concrete poured into two half-tunnel forms that together form the walls and ceilings of a room. When this process is repeated, generally on a 24-hour cycle, residential units can be created very rapidly.

Tunnelform was used in the construction of the Coleman Building, the University of East Anglia’s new student accommodation, which was offi cially opened in October 2004. The building provides 401 en-suite study bedrooms arranged in house groups of 8 or 12, in an innovative layout that minimises stair and lift cores. It also offers six fully accessible rooms for students with disabilities and a number of rooms designed to be suitable for residents with allergies.

The new accommodation continues the theme of environmentally responsible buildings that characterises the campus. ‘Traditionally, making buildings more energy effi cient has been about using less energy to heat homes up by insulating them and making them more air tight,’ says Minson. ‘But actually there is an increasing danger of buildings overheating in summer. Thermal mass is an incredibly good way of preventing a building overheating,’ he explains, ‘and the use of concrete is a practical way of introducing thermal mass to a building’.

Hospital constructionWith an £8.5 billion hospital building programme underway (the biggest in the history of the NHS) the NHS been taking advantage of modern methods of construction to meet its objectives.

Terrapin has been a prominent name in off-site manufacture for 55 years and has been heavily involved in the provision of hospital buildings from single to multi-storey. One example of this has been at Pinderfi elds Hospital in Wakefi eld.

The new building for Pinderfi elds has a total fl oor area of 2,600 sq m in two storeys including four operating theatres on the ground fl oor, wards on the fi rst fl oor together with a plant room incorporated within the pitch of the roof. There will be a link to the existing hospital street. Externally the building will feature maintenance free stone aggregate cladding in sienna with pearl grey fascias, a cost effective method of enclosing the structure quickly.

The building employs Terrapin’s advanced steel frame M2 construction method which provides fast construction with a considerable degree of internal planning fl exibility.

Student accommodation at the University of East Anglia

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New standardFollowing extensive consultation with the construction sector and other stakeholders, BRE Certifi cation has launched the calibration stage of its new certifi cation standard for dwelling systems. This gives, for the fi rst time, an opportunity for off-site manufacturers to demonstrate the performance of their products.

Called the Standard For Dwellings LPS 2020, it provides manufacturers of prefabricated building systems and sub-systems for housing with a recognised benchmark against which they can test and certify their products. In addition to normal building performance criteria, it covers insurance and mortgage lender requirements such as durability, repairability and identifi cation.

OFFSITE2005The very wide range and applicability of off-site construction systems now available was demonstrated at the OFFSITE03 event in May 2003. Following the success of that event, MMC showcase – OFFSITE2005 – will be held on 6-9 June 2005.

Jointly organised by BRE and SmartLIFE, the 2005 event has generated a high level of support from the MMC industry, with sponsors already including: The Concrete Centre, English Partnerships, Hanson, the Insulating Concrete Formwork Association, Mtech, Ruukki, Scottsdale Construction Systems, Terrapin and Van Elle (see page 2).

Anyone wishing to sponsor, exhibit at or attend OFFSITE2005 at BRE, Watford on 6-9 June 2005 should visit www.offsite2005.com, call 01923 664766 or Email offsite2005@bre.co.uk

FoundationsOff-site techniques are promoted on the basis of the improvements in quality and effi ciency that can be achieved by reducing the number of activities carried out in the uncertain conditions of a construction site. However, all modular, panelised, frame or volumetric systems still require the ground to be prepared and foundations to be installed before their systems can be brought on site.

Foundation companies have responded by developing systems that rely almost entirely on components fabricated off site. One such company is Van Elle, whose ‘Smartfoot’ pre-cast, post-tensioned foundation technique brings many of the benefi ts of off-site manufacturer to foundation construction.

‘We can take the site plans and start casting the ground beams in our factory while the contractor or housebuilder is getting the site prepared,’ explains director Paul Jones. ‘The client gets benefi t of accuracy, and the quality of curing is better because it is carried out in controlled conditions.’

Van Elle will be exhibiting Smartfoot at the OFFSITE2005 MMC showcase in June, and offi cially launching their new Litefoot foundation innovation.

Smartfoot

Tunnelform construction

OFFSITE2005

Demonstrating MMC’s

ability to deliver quality:

- homes

- schools

- hospitals

- commercial buildings

that are:

- creatively designed

- energy efficient

- sustainable

- cost effective.

BRE, Watford. 6-9 June 2005

T 01923 664766E offsite2005@bre.co.ukW www.offsite2005.com

Pinderfi elds Hospital

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07/08

CHANGES TO GUIDANCE FOR CONCRETE IN THE GROUNDNew information on factors contributing to sulfate attack of concrete in the ground has prompted a revision of a key guidance document. The proposed new guidance has been made available to the industry a for a short consultation period. Ian Longworth reports on the changes.

The guidance for concrete in aggressive ground, published in BRE Special Digest 1 (SD1), is currently undergoing a major revision. SD1 is nationally important guidance that is a companion document for the British Standard (BS 8500: Concrete) that covers the specifi cation of concrete for use in the UK.

The revision is being entirely funded by the construction industry, notably the Concrete Centre. A steering group of materials suppliers, concrete specialists and users has provided direction. This is the fi rst time in a 65-year history of BRE guidance for use of concrete in the ground, that no fi nancial backing or other support for preparation has been forthcoming from a government department.

BackgroundThe revision has been prompted principally by new knowledge about the thaumasite form of sulfate attack (TSA) that consumes the matrix of concrete. This form of attack is different to the ‘conventional’ form that produces the expansive mineral ettringite.

TSA was fi rst identifi ed in buried concrete in the UK a decade ago by BRE’s Dr Norah Crammond. Affected foundations of three domestic properties on sulfate-bearing clays of the Cotswolds area were all severely deteriorated. Subsequently, some 50 cases of TSA were found in the foundations of motorway bridges, many also in the Cotswolds area, but others as far fl ung as County Durham. Investigation and repairs to these structures have cost several millions of pounds.

Following national concern, the government set up a review body – the Thaumasite Expert Group (TEG) – in 1998, for which BRE provided technical expertise and a secretariat. Its report published in 19991, gave interim guidance on TSA and identifi ed areas needing research. Following extensive industry consultation in respect of practical issues, SD1 was published by BRE in 20012 to update existing Digest guidance in line with TEG recommendations.

What’s new Following four years of research by BRE and UK universities on the TEG listed areas, there is new knowledge about factors contributing to sulfate attack that warrants a major revision of SD1. Key outcomes are:

- A new ranking of cements with respect to sulfate resistance: some ‘binders’, particularly sulfate-resisting Portland cement, have hitherto been rated too high in respect of protecting against TSA, whilst others, notably blastfurnace slag based cements, have been previously underrated.

- Use of the concept ‘Aggregate Carbonate Range’ is no longer considered appropriate for partially determining the level of precautions against TSA. This is because cases of attack are now known to have occurred where the carbonate (required in addition to sulfate) has come from groundwater rather than from limestone in concrete aggregates,

- Whilst recommendations for sulfate resistance of concrete are based on performance in sulfate-bearing groundwater and analogous laboratory solutions, the construction industry tends to base its concrete specifi cation on sulfate concentrations in soil, determined by the 2:1 water/soil extraction test. Unfortunately, sulfate classes based on this test correlate poorly with sulfate classes based on sulfate in groundwater and, in general, concrete design based on this extraction test has a lower margin of safety against sulfate attack. A revision of the sulfate class limits is therefore called for (see right).

- An increased confi dence in the basic provisions for sulfate resistance enables guidance to be simplifi ed and the requirement for ‘additional protective measures’, such as surface protection of concrete to be reduced.

Changes to sulfate / sulfi de testing and classifi cationThe current and intended new limits for sulfate classes based on 2:1 water/soil extraction tests are as follows:

Sulfate class Current limits

g/l SO4

New limits

mg/l SO4

DS-1 < 1.2 < 500DS-2 1.2 – 2.3 500 – 1500DS-3 2.4 – 3.7 1600 – 3000DS-4 3.8 – 6.7 3100 – 6000DS-5 > 6.7 > 6000

This adjustment will make the ground classifi cation based on soil tests more conservative, eg some soils that were previously classifi ed as DS-2 would now be considered as being DS-3.

The change stems from fi ndings of numerous ground investigations carried out by BRE and others on research sites where concrete is exposed to sulfate-bearing ground and locations where TSA has occurred. In the majority of cases, the sulfate class limits based on soil extract tests were lower than those based on sulfate in groundwater, and were also low when compared to the actual occurrence of TSA. The new limits bring sulfate classifi cation based on the 2:1 water / soil extract tests into parity with the groundwater based tests.

Severe sulfate attack in a 30-year-old highway bridge sub-structure exposed to wet, pyritic clay fi ll.

Sample of formerly high quality concrete from highway bridge foundation that has been severely affected by TSA. The outer 50 mm of concrete has been reduced to a mushy reaction product rich in thaumasite. White haloes of pure thaumasite can be seen around dolomite aggregate particles.

Weald Clay

London Clay

Kimmeridge ClayOxford Clay

Lower Lias Clay

Mercia Mudstone (Keuiper Marl)

Limit of main areasof glacial deposits

Guidance for concrete in the ground in terms of sulfate classes based on sulfate in water/soil extracts was introduced in 1968, and updated in 1975 and 1991 as further information became available3. The most recent BRE research on sulfate classification based on soil sample assessment, provides an important step forwardin addressing the industry’s preference for soil sample tests. The new guidelines provide the precision now needed for concrete design, which itself has become a fi nely-tuned procedure.

Industry consultationBRE is aware that changing these sulfate class limits for concrete design may raise some queries in the construction community, particularly since the use of 2:1 water/soil extract tests for sulfate assessment has been extended to other areas, such as assessing the potential for corrosion of buried steel structures.

BRE is therefore making the proposed new text of SD1 available on the BRE web site at http://projects.bre.co.uk/sd1 for a consultation period ahead of its intended publication date in spring 2005. Comments from ground engineers and all those with an interest in this fi eld would be very welcome.

For further information – Norah Crammond, 01923 664367 Email crammondn@bre.co.uk

References1. Department of Environment, Transport and the Regions. Report of the Thaumasite Expert Group: The thaumasite form of sulfate attack: Risks, diagnosis, remedial works and guidance on new construction. DETR, January 1999.

2. BRE. Special Digest 1: Concrete in aggressive ground. CRC, London, 2001.

3. Longworth T I. Development of guidance on classifi cation of sulfate-bearing ground for concrete. Concrete. Vol 38, No 2, February 2004, pp 25 –26.

Principal sulfate and/or sulfi de-bearing strata in England and Wales. Precautions against sulfate attack on concrete in the ground frequently need to be taken in these areas.

T 01923 664200

E construction@bre.co.uk

W www.bre.co.uk

Testing & certification

Product development

Forensic investigations

Specification advice

Expert witness

Construction consultancy

09/10

Commercial buildings with a gross fl oor area of 1000m2 or more must demonstrate compliance with the airtightness levels set under Part L2 of the Building Regulations. In most instances this simply means putting the building through an airtightness test in the fi nal stages of construction. But for very large buildings, providing proof is much more complicated.

Terminal 5 is a huge project. The site is made up of the main concourse, a satellite terminal and a number of ancillary buildings – the main terminal alone could fi t 50 football pitches into its fi ve fl oors. From very early on it was apparent that it would be impossible to maintain suffi cient pressure to test the airtightness of the terminal buildings.

The Building Regulations have always recognised there could be problems with large buildings, so guidance from ODPM states that where this is the case the building control body should adopt an inspection regime to satisfy themselves of compliance. With Terminal 5, a quality control programme was devised to demonstrate airtightness compliance.

After a study to determine the best way of achieving the required level of airtightness quality control, the following regime was developed: - ongoing design reviews - training of site staff and operatives - regular meeting with Building Control.

It was important to integrate the airtightness quality control into BAA’s own quality control system, and to establish an audit trail. So right from the start, BRE’s airtightness experts worked closely with the client’s quality management team.

The airtightness experts needed to understand the special requirements associated with airport terminal design, and decide how these could be effectively dealt with. It was also important that they gained a good understanding of BAA’s management structure, contractual arrangements, quality control structure and procedures.

Design reviewDesigning buildings that are enveloped by a complete air barrier is best achieved through regular meetings between the design team and airtightness experts. There are two important aspects to consider – accidental leakage and planned openings.

Accidental leakage can account for more leakage than the total number of planned openings, so it is important to identify the likely leakage paths and see how they can be avoided through building detailing. This entails specifying particular materials and construction methods, and encouraging good workmanship. In the case of the Terminal 5 project, there is particular focus at eaves and on the roof structure.

Planned openings such as transit system tunnels and luggage conveyor openings, have been identifi ed and agreed with Building Control.

Site-staff/operatives awarenessWhilst it is important to ensure that a building is designed to be airtight, it is equally important that it is built to be airtight. Site operatives and supervisory staff must be familiar with Building Regulations requirements, and appreciate the importance of good workmanship and following instructions.

With Terminal 5, staff buy-in is being promoted through a series of targeted training sessions, organised and presented by BRE staff. Practical demonstrations explain why the airtightness measures are required, highlight where major leakage points are located, and remind everyone how their work affects the overall airtightness of the building. Training also covers any revisions made to the BAA quality control system.

Agreement with Building ControlAll stages of the construction process, from design to sign off, have been undertaken with the agreement of Building Control. If the design review, training and quality control activities are carried out with this agreement, full compliance will be achieved.

The procedures developed for Terminal 5 ensure that visual inspection effectively replaces the role of testing, but it is important not to underestimates the task. Regular liaison with Building Control is essential, and approval of methodology and programme statement must be gained before work commences.

In conclusion, whilst large buildings can present a problem, the issues are never insurmountable. What must be remembered is that they generally require an individual approach – methods used on one won’t necessarily work on another.

For more information – Chris Scivyer, 01923 664500Email scivyerc@bre.co.uk

AIRTIGHTNESSIN LARGE BUILDINGSDemonstrating the required airtightness of a very large building is a highly complex task. Chris Scivyer explains how a process was devised to satisfy building control that Heathrow Terminal 5 will comply with the Building Regulations.

11/1211/12DISABILITY DISCRIMINATION ACT (DDA)The fi nal stage of the DDA 1995, Part III, Access to Goods, Facilities and Services, came into effect on 1 October 2004. Architect and access consultant, David Bonnett, looks at the impact of this and at some common misconceptions.

Service providers now have a legal duty and obligation to disabled users. The DDA 1995 requires that reasonable adjustments be made to the physical features of their premises where barriers such as steps make it diffi cult for disabled people to access their services.

The new Approved Document Part M Access to and use of buildings of the Building Regulations 2004, introduced in May 2004, advocates inclusive design principles and introduces the Access Statement as a mechanism to demonstrate that reasonable access can or will be provided.

Architects’ reaction to the Part M revisionsThe incorporation of accessible design into architectural practice over the last 20 years has happened, albeit slowly and incrementally. It has resulted from a variety of regulatory pressures, social demands and fi nancial incentives. These in turn have gained ground, though unevenly, according to building type and use.

This is because Part M has even now not won the hearts nor, more pertinently, the minds of architects. Until recently with the concept of inclusive design, the Regulations have not presented a big and convincing idea, so most architects have developed and responded to personal conventions.

Now we have the DDA – more critically its fi nal part relating to ‘reasonable adjustments’ to buildings – but it has caused more of a stir with developers and facilities managers than with designers. How so?

This is because, unlike developers and managers, architects are at a distance from the consequences of their decisions with regard to the DDA. Managers now have to, on a day-to-day basis, resolve issues of confl ict between the suitability of building design and the requirements of disabled users. Developers are having to negotiate with nervous tenants and their lawyers and insurers. They are now at the coal face of coping with the DDA and, unlike in many other innovatory design practices, it is the developers exhorting their architects to join the real world rather than the other way around.

This will eventually change because of the new laws, but more rapid change will result from discussing and understanding inclusive design, its rationale and benefi ts. Meanwhile, at this relatively early stage, it is as well to know that defi nitions of inclusive design are still in debate, even among its most ardent supporters.

Nevertheless, the more prominent architectural practices are already responding to the sound arguments of inclusivity, and achieving some striking successes. And where the big names lead the others will surely follow.

Common misconceptions Common misconception 1: there is a clear and direct link between Part M 2004 and the DDA 1995.The DDA Part III 1995 prohibits access to goods, facilities and services from being impossible or unreasonably diffi cult on the grounds of disability. Where this is the case ‘reasonable adjustments’ must be made.

Making such adjustments to buildings is only one of three ways of addressing a problem. Altering policies, practices and procedures or providing auxiliary aids and equipment may be equally valid in some circumstances. It is for the service provider to decide on the best course of action.

By contrast, Part M 2004 sets prescriptive design standards in relation to a restricted number of physical design features. Adopting these does not of itself ensure that the duties and obligations of the DDA have been met.

Common misconception 2: the Part M revisions only deal with physical or wheelchair access to buildings. The concept of ‘access for all’ is based on an ‘inclusive’ approach to design whereby all users (such as parents with baby-buggies) and not just disabled users are taken into account. A useful defi nition of this is: ‘Inclusive design can be easily used by as many people as possible without undue effort, special treatment or separation.’ (Disability Rights Commission 2004.)

The revised Part M 2004 now takes further account of sensory and intellectual, as well as physical disabilities, through greater reference to environmental aspects such as lighting, textures and fi nishes, colour and contrast, and wayfi nding considerations such as signage.

Common misconception 3: the prescriptive nature of Part M 2004 straight-jackets the creative elements of the architect’s job.While Approved Document Part M 2004 sets out prescriptive access requirements which if met are guaranteed approval, it does not insist that these are the only way to gain approval. Designers can employ innovation solutions to meet the access principles set out in Part M, using the Access Statement to justify these. The Statement allows for discussions between designer and approving offi cer to arrive at a solution, and in a transparent way. This is sometimes referred to as the ‘access audit trail’ which can be used in court.

Conversely the Statement invites the architect to provide an explanation of why minimum standards cannot be achieved, for example in an historic building where practical constraints preclude a physical solution. Here the challenge is to think outside of built solutions and rely instead on other ‘adjustments’.

Common misconception 4: access and conservation issues relating to historic buildings are at odds with each other.Part M 2004 requirements can apply to an existing, even listed, buildings. But this can provide an opportunity for exciting, bold changes that may help ensure a revitalised and extended life for many public buildings designed in an earlier age with different values and objectives.

Even where dealing with obvious barriers to physical access may not be possible, for example steps into a building, other improvements such as staff assistance or virtual tours can be provided – or enhanced acoustics, lighting or equipment – which can be readily accommodated without disturbing the building fabric.

For more information – Stephen Garvin, 01355 576200Email garvins@bre.co.uk

‘Inclusive design can be easily used by as many people as possible without undue effort, special treat-ment or separation.’ Disability Rights Commission 2004.

Contact the Innovation Discovery Programme

T 01923 664658E Innovation@bre.co.uk W www.bre.co.uk/idp

Innovation Discovery Programme

BRE and Inventa can unlock innovation in your company.

If you need to:

- resolve problems

- get ahead of the competition

- open new markets

- improve margins/ increase revenues

- comply with future legislation

innovation could provide the answer.

11/12

PHOTOVOLTAICS FIELD TRIAL — INITIAL RESULTSDetailed information on the design, installation and performance of photovoltaic systems installed in 217 homes across the UK is being gathered in a six-year fi eld trial. This article looks at the initial fi ndings.

Whilst the technology to generate power directly from solar energy has been available for many years, it remains largely underused by the UK building sector. Photovoltaic (PV) systems can provide more than 40% of a home’s electricity requirements, so has great potential as a renewable energy resource.

To provide the construction industry with more information on the technology, the DTI has funded a six-year fi eld trial* that studies the design, installation and performance of PV in housing.

Stage oneThe fi rst stage of the project is gathering extensive information on the buildability, operating performance, reliability and maintenance of domestic PV installations. It is tracking the design, construction and installation of over 470 PV systems in 217 dwellings across the UK. Interference between neighbouring systems is also being looked at, as this is of particular concern to the electricity supply industry.

It is essential that the information gleaned from the study is as wide-ranging as possible, so the sample covers a range of locations, electricity suppliers, house types, module types and integration methods and involves social and private housing, refurbishment and new build.

CommunicationCommunication is key, particularly when a new technology is introduced into the construction process. Initial results show that good contractual arrangements will minimise misunderstandings. Contracts should be carefully considered and clear so that everybody involved knows what they are responsible for. Similarly, the allocation of responsibilities at an early stage avoids problems with damage and insurance claims should anything go wrong.

Late deliveries incur additional costs, so well-planned logistics are critical in minimising costs and maintaining good working relationships. Good coordination between PV installers and other trades – particularly roofers and electricians – will help ensure adherence to quality and the building schedule. Maintaining continuity of contract workers will minimise the need for additional training.

Good communication should not be confi ned to those involved in the construction phase. Close liaison with the electricity distribution and supply companies will minimise connection problems, and tenants are more likely to support an installation if they feel that they have been consulted and involved in the process.

Site and locationThe project has brought to light a number of issues related to both the siting of PV systems and the location of the installations. Firstly, designers must ensure that PV products comply with British Standards. Most PV products are imported and therefore not necessarily certifi ed to UK standards, even though they might comply with EU standards. For example, when Building Control asked for a PV product from Germany to be tested to BS 476, it failed the Spread of Flame test. This meant the product had to be modifi ed to meet British Standards and tested again before it could be installed.

Designers and contractors must take account of regional variations in Building Regulations, as differences can result in increased installation time and higher costs. Scottish Building Regulations, for example, require tiles to be nailed to the roof battens, due to the need for greater wind and infi ltration resistance. Sarking (ply and felt) is used instead of battens above felt, which means the solar tile hooks have to be made to different dimensions.

The study has shown that mounting systems need to be adaptable to allow for on-site modifi cations where roofs are irregularly shaped or vary from the expected layout. Vandalism was a problem on some sites, and where this might be an issue, measures should be taken to provide protection.

Finally, it is important to make sure the electricity meter is compatible with the PV system – some prepayment meters do not allow electricity export and can be damaged if this is attempted.

13/14

17 18

Good practiceStandards and regulations need to be adhered to for installation, labelling, health and safety, etc. This is important from a technical point of view, but also improves customer perception. Handover documentation must be well-prepared and cover all of the necessary points, particularly safety aspects. It is likely that each dwelling will change occupier several times within the lifetime of the PV system, so documentation must meet the needs of future occupiers.

CostCost were found to vary considerably between sites. Most of the retrofi t sites had above-average installation costs, due to the systems being add-ons, rather than integrated processes. More effort and more man-days are required to add a system to an existing building than for a new build, where it can be included at the design stage. Tile-integrated installations were the most expensive, mainly due to the high cost of the tile PV system.

The majority of other installations were much cheaper, with new-build frame-mounted installations coming in as the cheapest option. Signifi cant savings can be achieved when integrating frame-mounted systems into new build, as the costs of site works, storage and scaffolding are shared by other construction works.

Figures show that module and installation costs are falling year by year. This is thought to be a result of the introduction of capital grants, which not only increase demand, but also give positive signals to the PV industry. Reduced costs also indicate that the UK’s PV market is moving towards a more streamlined process.

Stage twoThe second stage of the project monitors the day-to-day performance of each PV system. Data is being collected and analysed over a period of two years, which will allow the system designs and climatic conditions to be compared both on a short-term and long-term basis.

One of the main concerns about PV is that the UK does not get enough sunshine for it to be viable. This would not seem to be the case. The fi ndings so far show that, even with a moderately sized system, a signifi cant proportion of a dwelling’s electricity requirements can be obtained in the UK climate – over 40% on average.

And whilst almost all of the sites had systems where outputs were lower than expected, this was usually caused by shading from other buildings or trees, and occasionally from the home itself.

In all cases, the PV systems have been easily accommodated on the roofs, and larger installations could have been fi tted for most sites had it not been for cost restrictions.

As only a few systems are providing regular data at present, the results of the analysis are preliminary. Most remaining projects are expected to start providing data this year and, at this point, the monitoring process will be extended to consider issues such as inverter sizing, array effi ciencies and fl uctuation in export and load levels. Overall there is still a considerable amount of important information to be gained. The next Annual Technical Report will be available shortly and the fi nal results will follow early in 2006.

For more information – BRE Environment, 01923 664500Email environment@bre.co.uk

*The UK Photovoltaic Domestic Field Trial has been funded under the DTI’s New and Renewable Energy Programme. BRE is responsible for co-ordinating the project teams involved.

Building schoolsConstruction contractors, suppliers and offsite manufacturers

will be at the forefront of delivering the £30 billion Building Schools for the Future programme.

A conference on the construction issues involved is being held on 3 March 2005 at BRE,Watford.

T 01923 664800 E events@bre.co.uk

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