The buildings subject of our structural investigation, assessment & structural appraisal were all of high rise LPS construction located across three separate estates in Barnet, built in the late 1960’s (at or around the time of Ronan Point disaster).

Site inspections were carried out during invasive investigations, to monitor operations and provide advice and guidance in relation to detailed requirements for opening-up of the pre-cast panel joint connections and testing of wall and floor slabs. Information from this formed the basis of our initial assessment and development of an interpretive report, which in some cases included recommendations for further investigations, detailed appraisal requiring justification by structural calculation and the introduction of possible controls and mitigation measures. In most cases this meant that the existing piped gas supplies had to be disconnected. At this stage the recommendation was based upon engineering judgement, following careful consideration of the condition of the in-situ concrete stitch ties of the wall panels.

The findings of the investigations found that buildings did not meet the minimum requirements for robustness as stated in Building Regulations Approved Document A3 (e.g., the requirement for effective horizontal and vertical ties. Therefore, a more detailed assessment of the building was required to ascertain its robustness under normal and accidental loading, e.g., Stage 3 and Stage 4 assessment.

The Stage 3 and 4 assessment included detailed calculations of wall and floor panels and in-situ joints to resist the loadings and, where failure of a structural element occurs, the ability of the remaining structure to support the loads without disproportionate collapse occurring.