0.8 Durability, workmanship and fitness of materials
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Regulation 8 applies to all building work, and requires that materials, fittings and components used in the construction of buildings should be suitable for their purpose, correctly used or applied, and sufficiently durable, taking account of normal maintenance practices, to meet the requirements of these regulations. For example, external timber cladding for low-rise buildings that is readily accessible and replaceable need not be as durable as that which is to be used at a higher level on medium-rise buildings.
It also implements the European Regulation 305/2011/EU Construction Products Regulation (CPR), in force on 1 July 2013 that replaces the current Construction Products Directive (89/106/EEC). This Regulation requires that products covered by a harmonised European product standard or conforming to a European Technical Assessment should normally have CE marking.
The intention of the guidance below is to provide adequate flexibility to accommodate new techniques as well as proven traditional practices. This guidance ensures acceptance of products which satisfy the basic works requirements of the CPR to avoid barriers to trade. For example, products bearing a CE mark (European Mark of Conformity) must be accepted as meeting regulation requirements where the declaration of performance satisfies the requirement and the product is being correctly used.
Sections 1 - 7 of the Technical Handbooks are arranged to equate with the 7 basic works requirements of the CPR. This should aid assessment of products against the regulation requirements. There may however be other Directives applicable to certain products or constructions.
A verifier may only reject CE marked products if the declaration of performance does not meet the regulation requirement or the products are being incorrectly used. If the verifier rejects a product the relevant trading standards officer should be notified. This is a requirement of the CPR, and will enable the UK government, where necessary, to notify the European Commission.
It should be noted that CE marking alone does not show compliance with the building regulations, as the CE mark may be showing compliance with other Directives or Regulations applicable to certain products or constructions. For example, a self contained smoke alarm, manufactured in accordance with the Electro Magnetic Compatibility Directive should be accepted as satisfying requirements only insofar as they relate to prevention of electromagnetic disturbances by, and prevention against disturbances to, such smoke alarms.
There are useful terms and acronyms used in this section included below.
BSI - The British Standards Institution is the UK national standards body. BSI publishes European standards in the UK as BS EN. See http://www.bsi.org.uk.
CEN - Comité Européen de Normalisation is the European standards body that prepares harmonised product standards. Declarations of Performance against such standards are expected to provide sufficient information for any member state to allow the product onto their market and for specifiers and users to be able to assess whether the product is suitable for its intended use.
CEN also prepares non-harmonised European standards, such as test or calculation standards and standards for products or services that have not been mandated under a CE Marking Directive.
CEN does not issue standards directly, only through national standards bodies; BSI is the designated standards body for the UK. Further information is available at http://www.cen.eu/cen.
EA - The European co-operation on Accreditation is the umbrella organisation for all National Accreditation Bodies in Europe. Product certification bodies, inspection bodies and test laboratories approved by national accreditation bodies belonging to EA are equivalent to those approved by UKAS. See http://www.european-accreditation.org/.
ETA - European Technical Assessments is a favourable technical assessment issued under the European Construction Products Regulation 2011 that allows a manufacturer to affix CE markings on their products. See http://www.eota.eu/.
ISO - International Organization for Standardization is the worldwide federation of national standards institutions. Standards are identified by ‘ISO’ and a number. ISO standards may be published separately or transposed into the UK as BS ISO or BS EN ISO. See http://www.iso.org/.
Materials - include manufactured products such as components, fittings, items of equipment and systems. Naturally occurring materials such as stone, timber and thatch, and backfilling for excavations in connection with building work are also included.
NANDO - New Approach Notified and Designated Organisations is an information system produced by the European Commission. It lists the harmonised European standards and bodies notified by member states to carry out conformity assessment tasks for CE marking. See http://ec.europa.eu/enterprise/newapproach/nando.
UKAS - United Kingdom Accreditation Service is the sole national accreditation body recognised by the UK Government to assess against internationally agreed standards, organisations that provide certification, testing, inspection and calibration services. Accreditation by UKAS demonstrates the competence, impartiality and performance capability of these organisations. See http://www.ukas.com/.
Verifier - the role of the verifier is to protect the public interest by providing an independent check of applications for building warrant to construct or demolish buildings, to provide services, fittings or equipment in buildings, or to convert buildings. Verifiers are appointed by Scottish Ministers.
Regulation 8 will be met if the following are satisfied:
materials used in the construction of buildings are of a suitable nature, quality and in relation to the purposes and conditions of their use, and
workmanship is such that, where relevant, materials are adequately mixed or prepared and applied, used or fixed so as to perform suitably the functions for which they are intended.
Materials include:
manufactured products such as components, fittings, items of equipment and systems
naturally occurring materials such as stone, timber and thatch, and
backfilling for excavations in connection with building work.
Building work must meet the functional requirements of Schedule 5 of the Building (Scotland) Regulations 2004, as amended. The Technical Handbooks refer to materials covered by European harmonised product standards, British Standards, and other technical specifications. However, as there is no obligation to adopt any particular solution contained in the Technical Handbooks in order to meet functional requirements, the references are not exclusive and other materials may be suitable in the particular circumstances.
The fitness and suitability of a material for use for a specific purpose can be assessed in the following number of ways.
CE marking under the CPR
Many materials are construction products that have CE marking under the CPR (305/2011/EU-CPR).
The CPR requires that construction products on the EU market covered by a harmonised European product standard should normally have CE marking. In addition, manufacturers of products not covered by a harmonised standard can choose to affix CE marking to their products by obtaining a European Technical Assessment. You can find a list of the harmonised product standards under the CPR on the NANDO information system see www.ec.europa.eu/enterprise/newapproach/nando/index.cfm?fuseaction=cpd.hs.
CE marking includes the reference of the product standard and levels or classes of performance being declared against some or all of the characteristics covered by the standard. The CE marking should be on the product, its label, the packaging or accompanying documents. The CE symbol by itself does not necessarily indicate that the material is suitable for building work.
In addition to CE marking, the product will have a declaration of performance containing more detailed information on the product. This may be a paper or electronic document, or it may be on a website. It is essential to check that the declared performance is suitable for building work.
In the absence of indications to the contrary, the verifier should assume that the information given in the CE marking and declaration of performance is accurate and reliable, and that the product meets the declared performances.
If the declared performance of a product is suitable for its intended use, the verifier should not prohibit or impede the use of the product.
CE marking under other EU Directives and Regulations
Products may have CE marking under other European legislation, such as the Gas Appliances Directive (2009/142/EC) or the Pressure Equipment Directive (97/23/EC). Such CE marking shows that the product meets the essential requirements set out in the legislation, for example, minimum safety requirements, and can be placed on the EU market.
Some products will have CE marking in accordance with both the CPR and other legislation. The CE marking shows that the product complies with the requirements in all relevant EU legislation.
British Standards
Nearly all British Standards for construction products are the British version of harmonised European Standards used for CE marking. The British Standards Institution (BSI) numbering policy is to adopt the European Committee for Standardisation (CEN) numbering, prefaced with BS e.g. BS EN 197-1: 2000.
Some British Standards are the British version of non-harmonised European standards; these also adopt the CEN numbering, prefaced with BS. These do not contain an Annex ZA, so CE marking cannot be affixed to products made to these standards.
Some British Standards for products not covered by a European standard will continue to exist.
Where a construction product has been made and assessed in accordance with one or more British Standards, this may show whether the product is suitable for its intended use.
Other national and international technical specifications
An international technical specification, including those prepared by the International Organization for Standardization (ISO) http://www.iso.org/iso/home.html, or on a national technical specification of a country other than the UK, may be used to demonstrate that a product not covered by a harmonised European standard meets the performance requirements of the Building Regulations.
Where necessary, the ‘relevant person’ who intends to carry out the work should obtain translations of specifications to demonstrate how the material meets the requirements of regulation 8.
It should be noted that the national technical specifications of other EU Member States (and non-EU countries that are full members of CEN) are being progressively replaced by harmonised European standards, as is the case with British Standards.
Independent certification schemes
There are many independent product certification schemes in the UK and elsewhere which may be a further source of information on product performance. Such schemes certify that a material complies with the requirements of a recognised document and indicates it is suitable for its intended use. These may be in addition to, but not conflict with, CE marking. It should be noted that, materials which are not certified by an independent scheme may still conform to a relevant standard.
Accreditation of a certification body by a national accreditation body belonging to the European co-operation on Accreditation (EA) provides a means of demonstrating that their certification scheme can be relied upon. In the UK, most independent certification bodies are accredited by UK Accreditation Service (UKAS), which belongs to the EA.
It is important to check the scope of the accreditation of certification body, as accreditation may cover only part of the certification body’s testing or certification business.
Tests and calculations
Where there is no relevant harmonised European standard, tests, calculation or other means may be used to demonstrate that materials will be capable of performing the function for which they are intended. UKAS or an equivalent national accreditation body belonging to the EA may accredit the testing laboratories. This accreditation provides a means of showing that such tests can be relied on.
Past experience
Past experience, such as in buildings in use may show that materials can perform the function for which they are intended.
Some materials, in the absence of special care, may be considered unsuitable because of their rapid deterioration in relation to the expected life of the building.
Short-lived materials that are readily accessible for inspection, maintenance and replacement may meet the requirements of the regulations if the consequences of failure are not likely to be serious to the health or safety of persons in and around buildings.
If short-lived materials are not readily accessible for inspection, maintenance and replacement, and the consequences of failure are likely to be serious for health or safety, it is unlikely that the material will meet the requirements of the regulations.
The properties of some materials can change in certain environmental conditions. These changes can affect the performance of the materials over time.
Materials that are susceptible to changes in their properties may be used in building work and will meet the requirements of the regulations if the residual properties, including the structural properties:
can be estimated at the time of their incorporation in the work, and
are shown to be suitable for buildings to perform the function for which they are intended, for the expected life of the building.
The term workmanship has been included so that references to methods of establishing workmanship can be included in the Technical Handbooks. For example, where performance depends on the construction being carried out with a crucial standard of workmanship, say in the construction of separating walls in a dwelling, it will prove useful to consider the information provided in British Standard BS 8000.
It is not the intention that verifiers check workmanship generally, certainly not for purely aesthetic matters.
It may be useful to consider the following as ways of establishing the suitability of workmanship:
CE marking
For materials having a CE marking, workmanship may be specified in the relevant ETA or harmonised product standard.
Standards
Methods of carrying out different types of work are also given in British Standards or other appropriate technical specifications. It should be noted that the BS 8000 series of standards on workmanship on building sites combines guidance from other BSI codes and standards. These are:
BS EN ISO 9000: 2005 – Quality management systems. Fundamentals and vocabulary.
BS EN ISO 9000: 2008 – Quality management systems. Requirements.
BS 8000-1: 1989 - Workmanship on building sites. Code of practice for excavation and filling.
BS 8000-2-1: 1990 (AMD 9324 1997) - Workmanship on building sites. Code of practice for concrete work. Mixing and transporting concrete.
BS 8000-2-2: 1990 - Workmanship on building sites. Code of practice for concrete work. Sitework with in situ and precast concrete.
BS 8000-3: 2001 - Workmanship on building sites. Code of practice for masonry.
BS 8000-4: 1989 - Workmanship on building sites. Code of practice for waterproofing.
BS 8000-5: 1990 - Workmanship on building sites. Code of practice for carpentry, joinery and general fixings.
BS 8000-6: 1990 - Workmanship on building sites. Code of practice for slating and tiling of roofs and claddings.
BS 8000-7: 1990 - Workmanship on building sites. Code of practice for glazing.
BS 8000-8: 1994 - Workmanship on building sites. Code of practice for plasterboard partitions and dry linings.
BS 8000-9: 2003 - Workmanship on building sites. Cementitious levelling screeds and wearing screeds. Code of practice.
BS 8000-11: 2011 - Workmanship on building sites – Internal and external wall and floor tiling. Ceramic and agglomerated stone tiles, natural stone and terrazzo tiles and slabs, and mosaics. Code of practice.
BS 8000-12: 1989 - Workmanship on building sites. Code of practice for decorative wall coverings and painting.
BS 8000-13: 1989 - Workmanship on building sites. Code of practice for above ground drainage and sanitary appliances.
BS 8000-14: 1989 - Workmanship on building sites. Code of practice for below ground drainage.
BS 8000-15: 1990 - Workmanship on building sites. Code of practice for hot and cold water services (domestic scale).
BS 8000-16: 1997 (A1: 2010) - Workmanship on building sites. Code of practice for sealing joints in buildings using sealants.
Independent certification schemes
Some independent certification schemes specify how workmanship will deliver a declared level of performance. The relevant person carrying out the work should show that the workmanship will provide the appropriate level of protection and performance.
Schemes, including “Certification of design” and “Certification of constructions” that register installers of materials can provide a means of ensuring that work has been carried out by knowledgeable contractors to appropriate standards. See 0.8.9 Certification.
Management systems
The quality of workmanship is covered by a quality management scheme, such as one that complies with the relevant recommendations of BS EN ISO 9000, and related series of standards. There are a number of such UKAS accredited schemes.
Past experience
Past experience, such as in a building in use, may show that the method of workmanship is capable of performing the function for which it is intended.
Tests
Tests can be used to show that workmanship is appropriate for compliance with building regulations.
Those carrying out building work may voluntarily include testing to demonstrate that the work complies with the requirements of the building regulations.
Verifiers may request a ‘materials test’ under Section 41 (2) of the Building (Scotland) Act 2003 if they consider it necessary, to establish whether building work and materials comply with the requirements of regulations 8 and 9 of the Building (Scotland) Regulations 2004, as amended.