Across-the-board revisions to the Building Regulations are going to have a dramatic effect on every specifier this summer. Buro Happold's Tanya Ross talks us through the new approved documents – including those in Scotland and Northern Ireland – from A to V
The latest Revisions to the Building Regulations for England and Wales came into force on 1 January 2001, and are supported by Approved Documents providing guidance on how the requirements can be met. These documents are identified alphabetically A to N (although there is no I) and many of these have undergone revision in recent years. Further approved documents are anticipated within the next two years.

The documents that have been recently amended or are imminently to be amended are considered in more detail below.

Part A: Structures
Originally issued for consultation in August 2001, the proposed revisions were intended to address:

  • changes in materials, technology and best practice
  • the more onerous effects of climate change on structures (particularly the increased frequency of extreme weather)
  • clarifying guidance with regards to disproportionate collapse
  • changes in materials, technology and best practice to include further advice on cavity wall construction, wall ties, mortar mixes and bespoke cladding systems. The revisions also introduce guidance on protection against attack by the House Longhorn Beetle.

Climate change has been considered at some length, but actual changes to the regulations are limited. For example, although snow loadings may be reduced, no effective reduction in roof loadings is proposed as considerations of safe access to roofs for maintenance are not to be relaxed.

It is also anticipated that increased wind speeds will be addressed by changes to the appropriate British Standard on wind loadings, rather than via the Building Regulations. However, it is acknowledged that long-term temperature rise has an impact on appropriate foundation depths in shrinkable soil, and this section has been revised. There is also revised guidance on wall ties exposed to increased incidence of driving rain.

The separate section on disproportionate collapse has been rewritten, introducing a table advising on the nature of precautions required in common building types and uses (including stadiums and grandstands). The events of 11 September have caused this particular section to fall under intense scrutiny, and this has delayed publication and implementation of the revised document. A firm publication date is not yet set.

Part B: Fire safety
Approved Document B was only recently updated – the current version came into force in July 2001 – but amendments currently proposed will harmonise the regulations with recently introduced European legislation. This is expected to take the form of a European Supplement document, which will identify the appropriate technical specifications and supporting European test standards. However, the technical guidance itself remains unchanged. The impact, in practical terms, is that materials will be required to be tested in accordance with the European standards, and classified appropriately. Some materials may be classified as poorer performers than under the British Standards, and clarity of specification will become crucial.

Part E: Resistance to the passage of sound
The amendments to the Building Regulations Approved Document Part E are extended to encompass "rooms for residential purposes", which will include hostels, hotels, student accommodation, nurses' homes and elderly care facilities for the first time (see "Sound system"). The guidance covers sound insulation between dwellings and other buildings, as well as between rooms within a dwelling. Reverberation noise in common parts of accommodation blocks is also covered, and there is a section dealing with schools. If the government chooses not to accept the robust standard details being developed by the House Builders Federation, inspectors will have the authority to ask for pre-completion testing to prove satisfactory compliance.

Standards have generally been raised in an attempt to make homes quieter, with specific noise attenuation requirements for walls and floors. Heavyweight blocks are recommended, although manufacturers of aircrete-type blocks are free to provide their own test data to prove that their products comply with the requirement.

Part F: Ventilation
The section of the regulations that deals with minimum fresh air requirements and measures to eliminate condensation was always going to come under scrutiny once Part L and Part E had been amended. Envelope construction, now required to be more substantial for acoustic reasons, and more airtight for energy conservation reasons, is increasingly expected to mitigate the environment through natural ventilation, or "trickle" ventilation. Balancing these demands will necessitate a review of the guidance document, the extent of which has still not been determined. Expect consultation in the next 12 months, and a change to the minimum fresh air demand of eight litres per second per person.

Part H: Drainage and waste disposal
Updated last year, the new part H came into effect on 1 April 2002. Several adjustments to the regulations were included to ensure the correct provision of drainage from converted properties and to safeguard existing sewers.

New guidance on foul drainage includes the usage of low-flush WCs; the requirement for grease separators for buildings where hot food is prepared; provision of pumping stations for low-lying properties; protection from rats in drains and a minimum drain size of 150 mm diameter for private sewers.

In the wastewater section, there is further information on the use of drainage fields and reed beds, with a need for provision of clear maintenance information, while the rainwater section gives guidance on more sustainable forms of rainwater drainage. There is also guidance on space needs for the collection of recycled waste – to be separate from non-recycled waste – and access provisions thereto (see "Checklist", page 11).

Part J: Combustion appliances and fuel storage systems
Updated last year, the new part J came into effect on 1 April 2002. The revisions include updating references to British and European standards, rules on positioning fuel storage containers and guidance on protection against oil pollution through the ground. However, their main thrust is to clarify performance requirements of flues and air supplies. In particular, guidance is given on installing appliances to existing flues and fireplaces, and there are illustrations of acceptable fireplace constructions for a range of gas fire types.

Part L: Conservation of fuel and power
This regulation has now been sub-divided into two parts: L1 covering dwellings and L2 covering buildings other than dwellings. Both parts address certain fundamental changes in terms of measuring thermal performance, but they were split to make the documents easier to use. Changes common to both parts include:

  • guidance on overall performance of hot water systems
  • controls on types of light fittings to be used
  • requirements for provision of information to building users/occupiers
  • extension of the regulations to include certain repair works and replacement windows
  • empowerment of local authorities to test buildings for compliance
  • improved minimum U-values
  • guidance on reducing thermal bridging
  • requirements to minimise air leakage
  • advice relevant to conservation and restoration work in historic buildings.

Part L1, for dwellings, allows three methodologies for calculating heat losses: the elemental method; the target U-value method, and the carbon index method (which replaces the energy rating method). Part L2 for non-dwellings also allows three methodologies: the elemental method, the whole building method and the carbon emissions calculation method. These new methodologies are more rigorous than previous calculations, and are likely to require considerably more time and effort on behalf of designers to demonstrate compliance.

One other notable change to L1 is the extension that applies to conservatories.

Requirements under L2 include addressing buildings' summertime performance for the first time, including demands on the performance of air-conditioning and mechanical ventilation systems. These systems are now incorporated into calculations, as are atriums. Air leakage testing is made a requirement, with the possibility that buildings that "fail" are required to be dismantled and rebuilt.

Part P: Electrical systems
A new Approved Document P, Safety Requirements for Electrical Installation Work in Dwellings, was distributed for consultation in May, with responses required by 13 September 2002. Essentially, the document aims to give guidance to those carrying out electrical works in domestic property, on how to comply with the IEE Wiring Regulations 16th edition.

The intention is to ensure the safe design and installation of electrical systems given the proliferation of DIY activity. The revised version includes blank inspection and test certificates, which should be provided to confirm safe completion of any electrical installation work. The expectation is that electricians will self-certify their work, but that non-qualified installers (including the DIY enthusiast) will be required to have work checked.

Parts S and T
It is anticipated that two further approved documents may be added to the regulations within the coming year, covering security systems and telecommunications systems. As with Part P, the aim would be to impose controls and standards on the installation of increasingly sophisticated electrical and data systems.

The regulations now come under the aegis of the Office of the Deputy Prime Minister, which has indicated that the review is continuing. It seems likely that further revisions to the documentation can be expected in the next few years.

  • Scotland
    The sixth amendment to the Building Standards (Scotland) Regulations 1990 came into force on 4 March 2002, writes Alex Smith. The changes are as follows:

    Part A: General
    Amendments have been made to definitions and schedules to match revised requirements in other parts.

    Part B: Fitness of materials and workmanship
    This has been reworded to recognise the format and content of European product standards.

    Part D: Structural fire precautions
    The introduction of harmonised European Standards, arising from the implementation of the Construction Products Directive, has necessitated a complete revision to accommodate new test methods and nomenclature.

    Part E: Means of escape from fire, facilities for firefighting, means of warning of fire
    The facilities for firefighting have been revised to take account of current practice in fire brigades.

    Part J: Conservation of fuel and power
    This has been rewritten to introduce improved standards for thermal insulation and efficiency to help meet government commitments to reducing greenhouse gas emissions. The amended regulations will also bring conservatories of between 8 m2 and 30 m2 into Building Regulations control.

    Part M: Drainage and sanitary facilities
    This has been amended to take account of new sustainable drainage practices.

    Part R: Storage of waste
    Many prescriptive requirements have been removed to allow current practice in waste removal to be taken on.

    There will be a further review of Building Regulations in future, but not until after the introduction of a new system of building standards in Scotland. The consultation paper Improving Building Standards: Proposals is the final consultation on the legislative proposals leading towards the introduction of a new building bill in the Scottish Parliament in September this year. It is hoped that the bill will receive royal assent by May 2003.

  • Northern Ireland
    Given that amendments to regulations in have generally been made after changes are introduced in England and Wales, it is likely that revised parts of the Building Regulations in Northern Ireland will gradually follow their English and Welsh counterparts.

    A public consultation has just been completed on Part C, Preparation of site and resistance to moisture, relating to radon protection measures.

  • Regulations: Part A - L