Ingenieur Vol.79 July-Sept 2019 ingenieur 2019 july-sept | Page 11

Figure 6: Floor Layout Configuration for a PVM House (CIDB, 2019) Figure 7: Dimensions and Space Planning for the Plan and the Section of a PVM House (CIDB, 2019) For PVM construction, connections strongly influence the overall structural stability and the robustness of the assembly of the PVM. Therefore, connections should be designed to transfer horizontal forces (e.g. those caused by wind loading) and extreme forces in the event of accidents that cause loss of support (Figure 8). Adequate vertical shear transfer (for example, as a result of wind-induced uplifts or differential movements) between the units must be considered to maintain the integrity of the system. Figure 9 illustrates two extreme cases of loss of corner support or intermediate support due to the notional removal of part of the PVM ground floor. During the construction process, the possibility of misalignment of the floor, wall, and ceiling at the joints between the PVM units, either horizontally or vertically, needs to be considered. Details regarding the interface between the PVM and in- situ construction elements such as core walls, staircases, corridors, and other parts of buildings should be taken into account (Figure 10). Along with the design and construction process, MEP services should also be co-ordinated at an early stage and all constraints for installation and maintenance addressed to avoid impact on finished works in later stages. It is crucial that the upfront design is co-ordinated with the structural prefabrication components. Necessary openings, recesses, and concealed components in the PVM should be considered for structural strength, fire safety measures, and how they could be used in other relevant designs. Continuity and system integrity of all MEP services should be dealt with accordingly. Due to the modular nature of PVM, the MEP system components might have to be connected between PVM units. However, the connection methodology (if used) should not compromise the integrity and performance of the system. The installation of MEP services should enable ease of maintenance and account for future replacement when necessary, as well as allocate sufficient space to carry out installation, maintenance, and future replacement work. Typical MEP services in a building are fire protection, electrical wiring, extra low voltage equipment (ELVs), lightning protection, water supply, sanitary, heating, ventilation and air- 9