Structural inspection & assessment of historic buildings

The structural integrity of historic buildings is subject to many environmental factors; repair, regularity and quality as well as the use of suitable materials for repair purposes. The assessment of heritage and historic buildings differs in many ways from the inspection and assessment of more modern buildings.

Factors to consider in the inspection & assessment of historic buildings

  • The initial construction process and materials
  • The life cycle of the building itself. What stresses has it undergone to lead to any potential deterioration
  • Any alterations the building may have had over the years – sometimes necessitating sophisticated methods of analysis and inspection
  • The geometric data and structural behaviour of the materials used in the construction
  • Original documentation and drawings (to be used for guidance only), if available

Importance of inspection and assessment of historic building

When talking about the importance of the assessment and inspection of existing historic buildings, it is important to consider not only the conservation element – i.e. the preservation of buildings of historic value – but also the environmental and sustainability boosts that relate to the continued usage of existing buildings as well as the socio-political assets that they represent. Robert Szymborski CEng MICE, the MD of Simplify Structural Engineering says,

“The general idea is to extend the life of historic buildings by identifying any issues and carrying out any necessary repairs.”

The checklist for assessment and inspection of historic buildings (Source: M. Holicky & M. Sykora, 2012)

  • Specification of the assessment objectives requested by the client
  • Preliminary assessment
  • Study of all available documentation
  • Preliminary site inspection
  • Preliminary checks
  • Decision on need for immediate actions
  • Recommendation for a detailed assessment
  • Detailed assessment
  • Detailed documentary search
  • Detailed inspection
  • Material testing and determination of required actions
  • Determination of structural properties
  • Structural analysis
  • Verification of structural reliability
  • Report including proposal for construction intervention
  • Repeating the sequence if necessary

A holistic approach to the job

Often the assessment of historic buildings requires a multi-faceted approach combining research, on-site inspections and laboratory test. The use of the combined methods enable the Structural Engineer to gain a fuller understanding of just how a given building and its parts are performing and being stressed. Alongside these highly focussed tests, detailed visual surveys and constrained intrusive inspections work best.

When it comes to visual inspection of historic buildings, the key guiding principles include:

  • The buildings geometry
  • Seismic zone, where appropriate
  • The area’s overall topography
  • Construction information
  • Division of structural elements in vertical and horizontal terms
  • Division of elements in accordance to load-bearing behaviour
  • Decay state of each structural element
  • Combine all elements and offer a holistic interpretation

Resources and funding

Historic England provides a great resource and the opportunity to apply for funding for the inspection and conservation of historic buildings, recognising the issues that can apply to such buildings and the heritage value they have. They can also offer the following advice for projects:

  • Help in identifying the potential for future change of use
  • Help in brokering solutions between relevant parties

The stresses that historic buildings face as well as their importance as part of a country’s heritage and in providing environmentally friendly, sustainable options for change of use make the importance of proper structural assessment and inspection of historic buildings, a key concern.