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Extending the life of existing structures

This section of the Conservation Information Resource for Civil Engineers (CIRCE) provides selected information and guidance on methodologies and approaches that can be taken by civil and building engineers when working on conservation, restoration and extending the life of existing structures.

To find out more, simply click on the relevant panels below.

Methodology and approaches


Sources of information and guidance


  • Glossary - provides an overview of terminology used by conservation professionals
  • Abbreviations - details the abbreviations used throughout CIRCE

High-level, and generally non-technical guidance on conservation of existing structures and sites is available from the many national and international organisations dealing with heritage issues.

The following general papers have been published in The Structural Engineer:

The following general guidance has been published by various organisations:

The first step in the assessment of any existing structure is to determine its age.

Some guides are specific to historic buildings, for example:

Others focus on types of structure, e.g. buildings or bridges.

Others focus on techniques, e.g. Dating technology or on material specific methods such as Dendrochronology .

Information may also be found in local archives, local history groups or various heritage and preservation societies.

Many of the Conservation and Heritage Organisations mentioned elsewhere in CIRCE provide on-line databases and guidance, including:

Many of the Conservation and Heritage Organisations mentioned elsewhere in CIRCE provide on-line lists of their publications, available for sale or downloading, including:

Civil engineering history: engineers make history. Proceedings of the First National Symposium on Civil Engineering History, New York, ASCE, 1996 [207 pp]

Engineering History and Heritage: Proceedings of the 2nd National Congress on Civil Engineering History and Heritage, Boston, Massachusetts, ASCE, 1998 [184 pp]

International Engineering History and Heritage: Improving Bridges to ASCE's 150th Anniversary. Proceedings of the Third National Congress on Civil Engineering History and Heritage, Houston, Texas, ASCE, 2001 [500 pp]

American Civil Engineering History: The Pioneering Years. Proceedings of the Fourth National Congress on Civil Engineering History and Heritage, Washington, ASCE, 2002 [551 pp]

Baltimore Civil Engineering History. Proceedings of the Fifth National History and Heritage Congress at the 2004 Annual Civil Engineering Conference and Exposition, Baltimore, Maryland, ASCE, 2004 [352 pp]

Many international and national organisations hold conferences whose proceedings can be found in specialist libraries and, increasingly, on-line, but usually at a cost to non-members. These include:

Several professional organisations have registers for those who are accredited to work on conservation of existing structures. These are introduced in the Part 2 of the Conservation Compendium published in The Structural Engineer (2015) [3 pp].

The Conservation Accreditation Register for Engineers (CARE) identifies civil and structural engineers skilled in the conservation of historic structures and sites.

The Royal Institution of Chartered Surveyors has its own RICS Building Conservation Accreditation.

The RIBA Conservation Register identifies three levels of membership: Specialist Conservation Architect, Conservation Architect and Conservation Registrant.

The Register of Architects Accredited in Building Conservation exists for the benefit of clients and the structures they are responsible for.

The Institute of Historic Building Conservation (IHBC) is the professional body for building conservation practitioners and historic environment experts working in England, Northern Ireland, Scotland and Wales, with connections to the Republic of Ireland. It embraces professionals from all disciplines.

A large number of terms are used by engineers, architects and conservation and heritage professionals when discussing various types of work on existing structures such as buildings, bridges, fortifications, water mills and canals. These include:

  • Conservation
  • Restoration
  • Refurbishment
  • Preservation
  • Renovation
  • Retrofit
  • Remediation
  • Rehabilitation

There are also more general teams such as

  • Repair and maintenance
  • Extending the life of a structure
  • Asset management

And the related and wider-ranging activities of:

  • Archaeology, and
  • Industrial archaeology

Finally, much work on existing structures can be referred to as:

  • Work on heritage structures, buildings or monuments
  • Contributing to social, economic and environmental sustainability

Conservation Principles Policies and Guidance for the Sustainable Management of the Historic Environment published by Historic England contains useful guidance on these terms in the glossary. [78 pp] direct

The Guide to International Conservation Charters, published by Historic Environment Scotland also addresses terminology and types of work on heritage structures. [100 pp] direct

In these CIRCE web pages, the terms Conservation, Refurbishment and Extending the useful life are used most often.

Abbreviation Organisation or publication
ACI American Concrete Institute
APTI Association for Preservation Technology International
ACSCE American Society of Civil Engineers
ASTM American Society for Testing Materials
BRE Building Research Establishment
CARE Conservation Accreditation Register for Engineers
CEB Comité euro-international du béton / Euro-International Committee for Concrete
CIRIA Construction Industry Research and Information Association
DMBR Design Manual For Roads And Bridges
ECCE European Council of Civil Engineers
fib Fédération internationale du béton / International Federation for Structural Concrete
fip Fédération internationale de la précontrainte / International Federation for Prestressing)
ICE Institution of Civil Engineers
ICOMOS International Council on Monuments and Sites
ISCARSAH International Scientific Committee on the Analysis and Restoration of Structures of Architectural Heritage
IStructE Institution of Structural Engineers
PHEW Panel for Historical Engineering Works
RIBA Royal Institution of British Architects
RICS Royal Institution of Chartered Surveyors
TICCIH The International Committee for the Conservation of the Industrial Heritage