Subsidence of low rise buildings (2nd edition) (2000)

Originally published in March 1994, the 1st edition of the IStructE Guide Subsidence of low-rise buildings has been the authoritative reference on the subject, and has led to many improvements in the way claims on subsidence cases are handled, both procedurally and technically. Greater co-operation is now seen between Insurers and householders with many Insurers directly appointing Experts to investigate notified claims rather than putting the onus on the householder to prove a claim. The 2nd edition is being published to reflect current practice. Technically there has been a substantial reduction in the use of underpinning with greater consideration being given to less disruptive means of stabilising affected properties, e.g. tree management. It has recently been shown that trees and other large vegetation on clay subsoil are responsible for over 65% of all instances of subsidence damage to domestic properties. Consequently the new edition contains a chapter dedicated to trees and tree management. Extra advice also includes appendices on the Association of British Insurers Domestic Subsidence Agreement and their Tree Root Claims Agreement, and information on Building Regulations. Well illustrated, much in colour, the substantial report was generated by an IStructE task group chaired by Brian Clancy, a Past President of the Institution and currently Chairman of the Association of Consulting Engineers, who also led drafting of the 1st edition. This 2nd edition was also prepared by a multi-disciplinary Task Group including Arboriculturalists, Engineering Consultants and Contractors, Lenders, Loss Adjusters and Insurers. The chapters of the report consider:
• Background
• Explanation of terms
• Concerns of each party involved in dealing with the problem
• Insurance matters
• The causes of damage to buildings
• Initial appraisal of the property
• Further investigations
• Trees and tree management
• Subterranean, substructure and superstructure repairs
• Remedial works to properties damaged by subsidence
• Research & future activities
and appendices on mining subsidence, measures to minimise the effects of foundation movement, a sample certificate of structural adequacy, a specimen underpinning guarantee, the ABI Domestic Subsidence Agreement & Tree Root Claims Agreement, Building Regulations, and the Party Wall, etc. Act as well as acknowledgements of assistance. Subsidence claims now average around 40,000 cases a year and, with no indication that this rate will fall in the foreseeable future, subsidence will continue to remain a major issue. While primarily aimed at Structural Engineers, the Guide is written for a wide readership including Mortgage Lenders, Consulting Engineers, Property Valuers, Insurers, Builders, Solicitors, Surveyors, Loss Adjusters, Local Authorities and property owners.