The present work investigates the hydrodynamic properties of an H-shaped stratified floating porous structure under irregular wave conditions, simulated numerically using the Multi-domain Boundary Element Method (MDBEM) based on small amplitude wave theory. The unique arrangement of the H-shaped floating structure, which consists of a flange as a horizontal member and a web as a vertical member, has been observed to be effective in both wave reflection and wave trapping under regular wave conditions in various literature. The MDBEM technique is used to address the physical problem. This method is computationally efficient and easily adaptable to any arbitrary shape of a structure. This study considers a specific configuration of the H-shaped breakwater to be studied under both regular and irregular wave conditions. The outputs from the numerical study are compared with the results from the existing literature. When considering irregular wave conditions, the hydrodynamic parameters from the analysis are displayed as the spectral densities of different hydrodynamic parameters fluctuating against frequencies, and when considering regular wave conditions, they are displayed as contour diagrams. Five distinct sea states have their spectral densities examined in this study.