New Standard For Innovative Dwellings
Background
Modern methods of construction including off-site manufacture (such as panellised or volumetric pod construction) have arrived on the UK construction scene, and over the next ten years are expected to revolutionise the way buildings are designed and built. This is particularly so for housing.
Many factors are influencing this development, including Government policy (John Prescott's push for greater development in the South East growth areas), improved quality resulting from factory methods of manufacture, shortage of skilled workers, and the needs of social housing providers. Numerous reports, including Egan and the recent Barker review of housing have recommended greater take-up of modern methods of construction, and off-site manufacture in particular.
So why haven't we seen more of this approach before? Well, there was a lot of bad publicity associated with "pre-fabricated" buildings after the war. Also the construction industry is notoriously conservative and reluctant to change. Tried and tested masonry construction, and modern timber frame, maintain a high value in the market and sell well. Mortgage lenders and insurers in particular are wary of new technologies of this nature, many lenders maintaining a "black list" of building systems on which they are unwilling to offer a mortgage. BRE has recently produced a new handbook entitled "Non-traditional houses" which focuses on older (pre-1984) building systems and how they may be assessed - see http://www.brebookshop.com/ Insurers have issues around the resilience of these new systems to typical threats, such as a fire in the kitchen, burst pipe, wind storm, flooding, theft, etc. Insurers also need to know what the implications are for the repairability of the systems in terms of the cost and speed of repair. Lenders have specific concerns about the durability and the whole life cost of maintaining such properties and what effect this has on the value of the property and the security of their loans.
New Standard
To help address the concerns of mortgage lenders, insurers and others, and tackle some of these perception problems around new systems and to assist the market in development of high quality products, BRE Certification has over the last year been developing a technical standard to set performance requirements for the new generation of building systems for dwellings. The
Standard for Innovative Methods of Dwelling Construction, LPS 2020, has the support of the Council of Mortgage Lenders, the Association of British Insurers, and construction sector interests. An extensive programme of development and stakeholder consultation workshops resulted in the launch of the draft standard at the Office of the Deputy Prime Minister's Sustainable Communities Summit in Manchester in January 2005.
Purpose
This standard is one of a suite of Loss Prevention Standards (LPS) that have been prepared by BRE Certification Ltd to provide a route to certification for innovative building systems, sub-assemblies and elements used in dwelling construction. It addresses
- The lack of standards and guidance that cover new methods of construction for dwellings.
- The variable needs of different approval, regulators and warranty providers which result in manufacturers having to go through several expensive and time consuming testing and assessment procedures to satisfy each body.
- The inconsistency of each approval given (as they are essentially the outcome of a negotiation process between manufacturer and approval body, dependant on the product and how it is intended to be used). This makes direct comparisons difficult (no two approvals would be the same), especially for insurers and lenders who are trying to understand and control risk.
- The considerable pressure from government and others to increase the use of so called modern methods of construction in dwellings.
- The need for the insurance and lending sectors to be able to manage the risks of using innovative construction systems with limited track record (particularly given their historic experience).
LPS 2020 standard aims to:
- provide a single and consistent method for assessing the design and performance of innovative building systems that do not have an adequate track record in service in the UK
- ensure that the manufacture/factory production of innovative systems is controlled
- complement the control and inspection functions of existing warranty providers and building control
- check buildability and produce a checklist of key items that will need to be inspected on site to ensure adequate performance in the final dwelling
- give confidence to insurers, lenders and owners that innovative systems will perform adequately
- achieve equal treatment for insurance and lending as given to conventional dwellings under normal terms for insurance and lending
- enable manufacturers to demonstrate optional enhanced performance of specialist systems e.g enhanced flood resistance or fire performance or reduced environmental impact
- maintain a database of approved innovative systems constructed and their location to be used to trace systems for future maintenance.
Scope and Structure
The scope of the standard covers the assessment and certification of innovative building systems, sub-assemblies and elements:
- that are not wholly covered under current recognised standards and codes for dwelling construction,
- that have a limited track record of service in dwelling construction in the UK.
LPS 2020 sets out requirements for performance and methods of verification for innovative building products and systems that are used in dwellings. The Standard does not set requirements for specific materials, dimensions or design approaches, and therefore does not discriminate against any material type or form of construction.
The suite of LPS standards currently comprises the following:
LPS 2020: This is the core standard of the suite and covers generic performance requirements applicable to innovative dwelling construction. For applicants seeking LPS 2020 certification of elements and building systems compliance with this standard is mandatory. Building systems and elements will be expected to perform to the minimum requirements of Building Regulations for safety, functionality and durability. In addition, they will be assessed for a range of characteristics including durability, resilience, repairability, whole life performance, adaptability and the provision of guidance on installation and maintenance. Suppliers will be required to undergo regular audits of their factory production control systems, which contribute to ongoing quality and to help provide assurance that each unit delivered will perform as intended.
The suite of LPS standards also provides optional additional requirements for systems designed for enhanced performance. Compliance with these performance requirements is required when they are included either in specific dwellings specifications or when a dwelling supplier wants certification to this higher standard. These standards comprise:
LPS 2023: This covers enhanced fire performance and is intended to be utilised where dwellings are at high risk to fire spread or growth and where the resulting fire is likely to cause significant damage to the building itself, and/or significant disruptions to the intended use of the building.
LPS 2024: This covers enhanced energy performance and is intended to be utilised where dwellings are required to achieve a higher level of energy performance, as recommended by Energy Savings Trust?s best practice guidance for "Energy Efficiency in New Housing".
LPS 2025: This covers the security performance of entry/egress into/from dwelling structures and is intended to be utilised where dwellings are required to achieve higher security performance for the prevention of unauthorised entry into the dwelling.
LPS 2026: This covers flood resilience and is intended to be utilised where dwellings are likely to be constructed in high risk flooding zones.
LPS 2027: This covers environmental profiling of dwelling components and will be used to evaluate the environmental impact of the dwelling system.
The LPS 2020 standard and any of the optional standards selected will be used in association with detailed site and configuration specific design procedures and existing site installation /quality control supervision to realise particular dwelling developments.
Next Steps - Calibrating the Standard
The calibration of the LPS 2020 standard is a process designed to systematically review the standard to help refine specific details and to help ensure it's overall effectiveness to integrate the process of product assurance with design assurance and on-site quality assurance for the final dwelling. This process will be conducted with a representative group of manufacturers of building systems and components.
The assurance of the product is fairly straightforward and can be implemented by extending the scope of existing recognised product certification and technical approvals (i.e. BRE Certification, BBA, etc). The quality assurance of the installation / site-based inspection aspects can be implemented by extending existing site-based inspection services provided by Building Control and warrantee providers such as NHBC, Zurich, to cover additional core requirements identified in LPS 2020. Quality assurance of the design process is not as straightforward, and would need an approach that cover the professional skills involved and links to the design checks and approval process adopted by building control and planning. It is crucial that the standard interfaces smoothly with the operations of on-site inspectors such as building control and warranty providers. We will be working with them during the calibration period to make sure this happens.
Once the final approved standard is published, manufacturers and suppliers will be able to approach BRE Certification and its licensees to apply for the certification of their systems and components against the standard. The certification process will assess and validate claims of performance, technically evaluate designs and specifications, and regularly audit the quality control of factory operations. The scheme document which controls the operation of the approval scheme sets out the application process, appraisal procedures, how pre-existing test and other information will be handled, pass/fail criteria, performance grades, factory production control requirements and other matters.
Important comments made by a number of stakeholders are that they want to see a single, broadly accepted standard, but that this must not become a restriction on competition, so BRE Certification will be working with other assessment bodies to help provide the scheme through a number of channels. Site-based inspection of each constructed dwelling is important for mortgage lenders and other stakeholders. It is intended that this process will be carried out by bodies such as NHBC and Zurich, using the system-specific checklists on key aspects prone to design or installation error generated by the certification process, with reporting through the usual warranty inspection and certification system.
Role of the Regulator
Although regulators such as planners and building control officers see a wide range of building types as part of their work, many of these new building systems are extremely innovative and their proposed use will raise many questions about compliance and performance. This will impose a considerable administrative burden on regulators and suppliers. One of the key aspects of LPS 2020 is that it checks as many of the aspects of the Building Regulations as possible, so relieving this burden. It will, however, be important for site-based and design aspects to be examined on a case-by-case basis using the system specific checklists.
Regulators will be specifically interested in the site-based installation checklists resulting from the LPS 2020 approval process, as these will address regulatory issues where appropriate, in addition to the performance aspects.
The next few years will be an exciting time for the building system market, designers and contractors, and those professionals working with them such as ABE members. BRE Certification looks forward to working with all stakeholders to help provide a new stock of system built dwellings which have good performance and regulatory compliance.
More information can be obtained from BRE Certification, enquiries@brecertification.co.uk, Tel: 01923-664100.
© Copyright 2011 Means Of Escape Terms & Conditions Privacy Policy
Copyright © 2011 Think Agency - Website Designers Kent