The Optimal Model for Living Walls in South Africa: A Quantity Surveying Perspective

Living Wall Systems (LWS) are vertical vegetated building façade systems that offer environmental and social benefits; however, their adoption in South Africa, particularly within the Western Cape (WC), remains limited due to high capital and maintenance costs and the absence of regionally adapted design and cost models. This study investigates the viability and optimisation of LWS in the WC from a Quantity Surveying (QS) perspective, with the aim of developing a context-specific system utilising indigenous plant species and assessing its economic feasibility over the building life cycle. A mixed-method research approach was employed, comprising a review of relevant literature, semi-structured interviews with industry professionals, thematic analysis, cost modelling, and the preparation of a detailed Bill of Quantities (BOQ). Life cycle costing (LCC) techniques were applied to evaluate long-term cost implications. The study resulted in the development of an optimal LWS model, termed Viridis 5045, which satisfies identified environmental, technical, and contextual requirements for the WC. The BOQ, and LCC analyses provide projected capital and operational cost benchmarks for the proposed system. The findings indicate that Viridis 5045 is technically feasible and economically viable within the WC context, supporting its integration into sustainable construction practices. The study further identifies areas for future research, including the monetisation of long-term benefits, greywater integration, and the assessment of psychological impacts associated with green façades.